Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 37
Filtrar
1.
Int J Radiat Oncol Biol Phys ; 46(3): 599-607, 2000 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-10701739

RESUMEN

PURPOSE: The lack of any consistent correlation between radioimmunotherapy (RIT) dose and observed hematologic toxicity has made it difficult to validate RIT radiation dose estimates to marrow. Stable chromosomal translocations (SCT) which result after radiation exposure may be a biologic parameter that more closely correlates with RIT radiation dose. Increases in the frequency of SCT are observed after radiation exposure and are highly correlated with absorbed radiation dose. SCT are cumulative after multiple radiation doses and conserved through an extended number of cell divisions. The purpose of this study was to evaluate whether increases in SCT frequency were detectable in peripheral lymphocytes after RIT and whether the magnitude of these increases correlated with estimated radiation dose to marrow and whole body. METHODS AND MATERIALS: Patients entered in a Phase I dose escalation therapy trial each received 1-3 intravenous cycles of the radiolabeled anti- carcinoembryonic antigen (CEA) monoclonal antibody, 90Y-chimeric T84.66. Five mCi of 111In-chimeric T84.66 was co-administered for imaging and biodistribution purposes. Blood samples were collected immediately prior to the start of therapy and 5-6 weeks after each therapy cycle. Peripheral lymphocytes were harvested after 72 hours of phytohemagglutinin stimulation and metaphase spreads prepared. Spreads were then stained by fluorescence in situ hybridization (FISH) using commercially available chromosome paint probes to chromosomes 3 and 4. Approximately 1000 spreads were evaluated for each chromosome sample. Red marrow radiation doses were estimated using the AAPM algorithm and blood clearance curves. RESULTS: Eighteen patients were studied, each receiving at least one cycle of therapy ranging from 5-22 mCi/m2. Three patients received 2 cycles and two patients received 3 cycles of therapy. Cumulative estimated marrow doses ranged from 9.2 to 310 cGy. Increases in SCT frequencies were observed after each cycle for both chromosomes 3 and 4 in 16 of 18 patients and in at least one chromosome for the remaining 2 patients. Cumulative increases in SCT frequencies ranged from 0.001 to 0.046 with no major differences observed between chromosomes 3 and 4. A linear correlation between cumulative marrow dose and increases in SCT frequencies was observed for chromosome 3 (R2 = 0.63) and chromosome 4 (R2 = 0.80). A linear correlation was also observed between increases in SCT frequency and whole body radiation dose or administered activity (R2 = 0.67-0.89). There was less correlation between observed decrease in wbc or platelet counts and marrow dose, whole body dose, or administered activity (R2 = 0.28-0.43). CONCLUSIONS: Increases in SCT frequency were detectable in peripheral lymphocytes after low dose-rate RIT irradiation. A linear correlation was observed between increases in SCT and marrow dose, whole body dose, and administered activity. This correlation provides one of the strongest radiation dose-response and activity-response relationships observed with RIT. The detection of SCT may therefore have application as an in situ integrating biodosimeter after RIT. This biologic parameter should prove useful in comparing effects on marrow for different therapeutic radionuclides and in comparing effects of RIT and external beam radiation doses on a cGy per cGy basis. As a result, this should allow for a more direct comparison between different methods of irradiation and in further refinement of radioimmunotherapy dose estimates and dosimetry methodology.


Asunto(s)
Médula Ósea/efectos de la radiación , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/radioterapia , Radioinmunoterapia/efectos adversos , Translocación Genética , Cromosomas Humanos Par 3/efectos de la radiación , Cromosomas Humanos Par 4/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Humanos , Hibridación Fluorescente in Situ , Masculino , Análisis de Regresión
2.
Clin Cancer Res ; 5(10 Suppl): 3224s-3231s, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10541368

RESUMEN

cT84.66 is a human/murine IgG1 with high affinity and specificity for carcinoembryonic antigen (CEA). An earlier Phase I trial defined the maximum tolerated dose for 90Y-diethylenetriaminepentaacetic acid (DTPA)-cT84.66 at 22 mCi/m2. Dose-limiting toxicities were reversible leukopenia and thrombocytopenia. The purpose of this Phase I trial was to evaluate the feasibility and toxicities of administering higher activities of 90Y-DTPA-cT84.66 with stem cell support in patients with CEA-producing breast cancer. Patients with CEA-producing breast cancer refractory to standard therapies underwent peripheral stem cell collection followed by infusion of 111indium-DTPA-cT84.66. Those patients demonstrating tumor targeting received a single therapy dose of 90Y-DTPA-cT84.66, followed by Ca-DTPA infusion for 72 h posttherapy. Stem cells were reinfused following a divided schedule. To date, seven patients have been accrued to this trial. Each patient received an imaging dose of (111)In-cT84.66. Six patients demonstrated tumor imaging and received a single cycle of 90Y-cT84.66 at 15 mCi/m2 (three patients) and 22.5 mCi/m2 (three patients). One patient did not demonstrate tumor imaging and was not treated. At these administered activities, 90Y-cT84.66 was well tolerated. No dose-limiting toxicities have been observed. All patients demonstrated hematopoietic recovery after stem cell infusion. One patient demonstrated stable disease for 4 months; one patient had stable disease and reduction of bone pain for 3 months; and a third patient experienced >50% reduction of an ovarian metastasis, resolution of malignant pleural effusion, stable pleural metastases, and stable bone scan for 14 months. Preliminary results from this ongoing Phase I trial are promising and demonstrate the feasibility and potential for antitumor effects of stem cell supported 90Y-cT84.66 therapy in patients with CEA-producing breast cancers.


Asunto(s)
Neoplasias de la Mama/terapia , Antígeno Carcinoembrionario/inmunología , Trasplante de Células Madre Hematopoyéticas , Inmunoglobulina G/uso terapéutico , Radioinmunoensayo , Proteínas Recombinantes de Fusión/uso terapéutico , Radioisótopos de Itrio/uso terapéutico , Animales , Neoplasias de la Mama/metabolismo , Antígeno Carcinoembrionario/biosíntesis , Terapia Combinada , Femenino , Humanos , Ratones , Ácido Pentético/uso terapéutico , Radioinmunoensayo/efectos adversos , Trasplante Autólogo
3.
Gynecol Oncol ; 73(3): 402-6, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10366467

RESUMEN

OBJECTIVE: The purpose of this study was to examine ovarian histopathology in tamoxifen-treated breast cancer patients undergoing oophorectomy. METHODS: We reviewed the records and ovarian histopathology of 152 breast cancer patients who underwent oophorectomy at a single institution between January 1980 and October 1996. At the time of oophorectomy, 99 patients had never received tamoxifen, 44 patients were currently receiving tamoxifen, and 9 patients had previously received tamoxifen. Patient demographic and medical data and indication for oophorectomy were examined. Ovarian histopathology was classified as normal, functional ovarian cyst, benign ovarian tumor, endometriosis, ovarian cancer, and metastatic cancer. RESULTS: Patient characteristics and indication for oophorectomy did not differ significantly based on tamoxifen exposure. There was no difference in the occurrence of benign ovarian tumors, functional ovarian cysts, or metastatic breast cancer based on tamoxifen exposure. Tamoxifen-treated patients were less likely to have ovarian cancer, 0 of 53 patients (95% confidence interval (CI): 0.0%, 6.7%) compared with 10 of 99 patients (95% CI: 5.0%, 17.8%) patients not receiving tamoxifen (P = 0.015). Endometriosis was slightly more common in patients currently receiving tamoxifen, but the difference was not statistically significant. CONCLUSIONS: In women undergoing oophorectomy, there was no evidence that tamoxifen exposure was associated with an increase in benign or malignant primary or metastatic ovarian neoplasm or in functional ovarian cysts. Further study is necessary to better define any association between tamoxifen and endometriosis and the effect of tamoxifen on ovarian cancer risk.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Ovario/efectos de los fármacos , Ovario/patología , Tamoxifeno/uso terapéutico , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad
4.
Med Phys ; 26(5): 799-809, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10360545

RESUMEN

Intrapatient variation in the biodistribution of the chimeric monoclonal antibody cT84.66 was assessed in 19 patients having a variety of carcinoembryonic antigen (CEA) positive tumors. The two studies, including whole-body imaging and blood and urine specimen collections, were conducted within 14 days of each other using (111)In-cT84.66 at a fixed total protein dose of 5 mg per patient per study. An initial pretherapy infusion of (111)In-cT84.66 was administered followed by a therapy coinfusion of (111)In-ct84.66 and 90Y-cT84.66 A closed five-compartment model was used to integrate source organ activity curves as residence time inputs into the MIRDOSE3 program. Normal organ absorbed doses were estimated for 90Y-cT84.66, the corresponding radiotherapeutic agent. For the two (111)In-cT84.66 biodistributions, all data were modeled with a R2 value of between 0.72 and 1.00 with the exception of the urine data taken during therapy. This was due to the need of diethylenetriaminepentaacetic acid during the therapy phase because of the possibility that yttrium might escape from the chelator attached to the antibody. With the assurance that the biodistributions were reproducible, we were able to estimate the 90Y-cT84.66 absorbed doses on a per-patient basis. Concordance coefficients showing the agreement between the imaging and therapy phase dose estimates were between the 0.60 and 0.99 levels for liver, spleen, red marrow, total body, and other organ systems. Median results were: 27, 17, and 2.7 rad/mCi of 90Y-cT84.66 for liver, spleen, and red marrow, respectively. Because of decreases in platelets and white cells as the amount of 90Y was increased, dose-limiting toxicity was found at 22 mCi/m2. We conclude that patient biodistributions were consistent over time to 14 days so as to allow absorbed dose estimation in a radioimmunotherapy trial involving the cT84.66 anti-CEA antibody.


Asunto(s)
Radioinmunoterapia/métodos , Planificación de la Radioterapia Asistida por Computador , Radioisótopos de Itrio/uso terapéutico , Adulto , Anciano , Femenino , Humanos , Radioisótopos de Indio/sangre , Radioisótopos de Indio/orina , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Factores de Tiempo , Distribución Tisular , Radioisótopos de Itrio/sangre , Radioisótopos de Itrio/orina
5.
Ann Surg Oncol ; 6(3): 249-54, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10340883

RESUMEN

BACKGROUND: Inflammatory breast cancer is a locally advanced tumor with an aggressive local and systemic course. Treatment of this disease has been evolving over the last several decades. The aim of this study was to assess whether current therapies, both surgical and chemotherapeutic, are providing better local control (LC) and overall survival (OS). We also attempted to identify clinical and pathologic factors that may be associated with improved OS, disease-free survival (DFS), and LC. METHODS: A 25-year retrospective review performed at the City of Hope National Medical Center identified 90 patients with the diagnosis of inflammatory breast cancer. RESULTS: Of the 90 patients identified with inflammatory breast cancer, 33 received neoadjuvant therapy (NEO) consisting of chemotherapy followed by surgery with radiation (n = 26) and without radiation (n = 7). Fifty-seven patients received other therapies (nonNEO). Treatments received by the nonNEO group consisted of chemotherapy, radiation, mastectomy, adrenalectomy, and oophorectomy, alone or in combination. The median follow-up was 28.9 months for the NEO group and 17.6 months for the nonNEO group. Borderline significant differences in the OS distributions between the two groups were found (P = .10), with 3- and 5-year OS for the NEO group of 40.0% and 29.9% and for the nonNEO group of 24.7% and 16.5%, respectively. DFS and LC were comparable in the two groups. Lower stage was associated with an improved OS (P < .05). The 5-year OS for stage IIIB was 30.9%, compared to 7.8% for stage IV. In those patients with stage III disease who were treated with mastectomy and rendered free of disease, margin status was identified by univariate analysis to be a prognostic indicator for OS (P < .05). The 3-year OS, DFS, and LC for patients with negative margins were 47.4%, 37.5%, and 60.3%, respectively, compared to 0%, 16.7%, and 31.3% in patients with positive margins. CONCLUSIONS: This study suggests that in patients with inflammatory breast cancer and nonmetastatic disease, an aggressive surgical approach may be justified with the goal of a negative surgical margin. Achievement of this local control is associated with a better overall outcome for this subset of patients. The ability to obtain negative margins may further identify a group of patients with a less aggressive tumor biology that may be more responsive to other modalities of therapy.


Asunto(s)
Neoplasias de la Mama/terapia , Evaluación de Resultado en la Atención de Salud , Adulto , Anciano , Análisis de Varianza , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/mortalidad , Supervivencia sin Enfermedad , Femenino , Humanos , Modelos Logísticos , Los Angeles/epidemiología , Mastectomía , Persona de Mediana Edad , Terapia Neoadyuvante , Recurrencia Local de Neoplasia/epidemiología , Estadificación de Neoplasias , Radioterapia Adyuvante , Análisis de Regresión , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia
6.
Cancer ; 85(9): 1931-6, 1999 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-10223232

RESUMEN

BACKGROUND: The purpose of this study was to examine the clinical presentation, prognostic factors, and survival rates of patients with hepatocellular carcinoma (HCC) and to examine differences between Asian and non-Asian patients with HCC. METHODS: A review of the clinical characteristics and laboratory evaluations for 76 patients in two different broad ethnic groups (Asians [Group 1] and non-Asians [Group 2]) who underwent treatment for HCC from 1977-1995 was performed. Chi-square and Cox regression analyses were performed to assess factor interaction and association with survival. RESULTS: A total of 24 patients in Group 1 and 52 patients in Group 2 were reviewed. Of the clinical variables examined, a higher rate of a history of hepatitis B positivity was observed in Group 1 compared with Group 2 (32% vs. 6%; P=0.001). Among the 76 patients with HCC, a 1-year survival estimate of 41.4% was found. There was a borderline significant difference in survival between Group 1 and Group 2 with a 1-year survival estimate of 29.5% versus 46.9%, respectively (P=0.08). Better overall survival was found in patients who had tumors that were resectable (P=0.0001), had an alpha-fetoprotein level <10 ng/mL (P=0.02), or were a younger age at the time of diagnosis (P=0.01). There was a trend for Asian race (P=0.08) to be associated with poorer survival. When these risk factors were entered into a multivariate analysis, tumor resectability and non-Asian race were most predictive of improved survival (model P value = 0.007). When controlling for the multiple variables most often reported to be associated with HCC, Asians had a significantly lower survival than non-Asians (P<0.01). CONCLUSIONS: In this study it appears that the outcome for Asian patients with hepatoma is worse than for non-Asian patients, even when controlling for factors commonly associated with HCC. Biologic or social factors that are not appreciated currently may be involved in Asian patients with HCC, contributing to a poorer clinical outcome.


Asunto(s)
Carcinoma Hepatocelular/mortalidad , Etnicidad , Neoplasias Hepáticas/mortalidad , Adolescente , Adulto , Anciano , Asia/etnología , Población Negra , California , Niño , Femenino , Hispánicos o Latinos , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Análisis de Regresión , Factores de Riesgo , Tasa de Supervivencia , Población Blanca
7.
J Nucl Med ; 39(12): 2097-104, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9867150

RESUMEN

UNLABELLED: Chimeric T84.66 (cT84.66) is a high-affinity (1.16x10(11) M(-1)) IgG1 monoclonal antibody against carcinoembryonic antigen (CEA). The purpose of this pilot trial was to evaluate the tumor-targeting properties, biodistribution, pharmacokinetics and immunogenicity of 111In-labeled cT84.66 as a function of administered antibody protein dose. METHODS: Patients with CEA-producing colorectal cancers with localized disease or limited metastatic disease who were scheduled to undergo definitive surgical resection were each administered a single intravenous dose of 5 mg of isothiocyanatobenzyl diethylenetriaminepentaacetic acid-cT84.66, labeled with 5 mCi of 111In. Before receiving the radiolabeled antibody, patients received unlabeled diethylenetriaminepentaacetic acid-cT84.66. The amount of unlabeled antibody was 0, 20 or 100 mg, with five patients at each level. Serial blood samples, 24-hr urine collections and nuclear images were collected until 7 days postinfusion. Human antichimeric antibody response was assessed up to 6 mo postinfusion. RESULTS: Imaging of at least one known tumor site was performed in all 15 patients. Fifty-two lesions were analyzed, with an imaging sensitivity rate of 50.0% and a positive predictive value of 76.9%. The antibody detected tumors that were not detected by conventional means in three patients, resulting in a modification of surgical management. Interpatient variations in serum clearance rates were observed and were secondary to differences in clearance and metabolic rates of antibody and antibody:antigen complexes by the liver. Antibody uptake in primary tumors, metastatic sites and regional metastatic lymph nodes ranged from 0.4% to 134% injected dose/kg, resulting in estimated 90Y-cT84.66 radiation doses ranging from 0.3 to 193 cGy/mCi. Thirteen patients were evaluated 1-6 mo after infusion for human antichimeric antibody, and none developed a response. No major differences in tumor imaging, tumor uptake, pharmacokinetics or organ biodistribution were observed with increasing protein doses, although a trend toward increasing blood uptake and decreasing liver uptake was observed with increasing protein dose. CONCLUSION: Chimeric T84.66 demonstrated tumor targeting comparable to other radiolabeled intact anti-CEA monoclonal antibodies. Its immunogenicity after single administration was lower than murine monoclonal antibodies. These properties make 111In-cT84.66, or a lower molecular weight derivative, attractive for further evaluation as an imaging agent. Yttrium-90 dosimetry estimates predict potentially cytotoxic radiation doses to select tumor sites, which makes 90Y-cT84.66 also appropriate for further evaluation in Phase I radioimmunotherapy trials. Although clinically important changes in biodistribution, pharmacokinetics and tumor targeting with increasing protein doses of 111In-cT84.66 were not demonstrated, the results do suggest that antibody clearance from the blood is driven by hepatic uptake and metabolism, with more rapid blood clearance seen in patients with liver metastases. These patients with rapid clearance and potentially unfavorable biodistribution for imaging and therapy may, therefore, be a more appropriate subset in which to evaluate the role of administering higher protein doses. This underscores the need to further identify, characterize and understand those factors that influence the biodistribution and clearance of radiolabeled anti-CEA antibodies, to allow for better selection of patients for therapy and rational planning of radioimmunotherapy.


Asunto(s)
Neoplasias Colorrectales/radioterapia , Neoplasias Colorrectales/cirugía , Radioisótopos de Indio/uso terapéutico , Adulto , Anciano , Animales , Anticuerpos Monoclonales/efectos adversos , Antígeno Carcinoembrionario/inmunología , Neoplasias Colorrectales/diagnóstico por imagen , Neoplasias Colorrectales/patología , Femenino , Humanos , Inmunoglobulina G/efectos adversos , Radioisótopos de Indio/efectos adversos , Radioisótopos de Indio/farmacocinética , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/secundario , Metástasis Linfática , Masculino , Tasa de Depuración Metabólica , Ratones , Persona de Mediana Edad , Metástasis de la Neoplasia , Proyectos Piloto , Radiografía , Radioinmunoterapia , Cintigrafía , Radiofármacos/efectos adversos , Radiofármacos/farmacocinética , Radiofármacos/uso terapéutico , Dosificación Radioterapéutica , Radioterapia Adyuvante , Sensibilidad y Especificidad , Distribución Tisular
8.
Am J Obstet Gynecol ; 178(6): 1145-50, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9662294

RESUMEN

OBJECTIVE: This study was conducted to examine the histopathologic changes in tamoxifen-treated postmenopausal patients with endometrial thickness > or = 5 mm with transvaginal ultrasonography. STUDY DESIGN: Thirty-five tamoxifen-treated postmenopausal breast cancer patients underwent transvaginal pelvic ultrasonography with endometrial thickness > or = 5 mm followed by either curettage-hysteroscopy (n = 24), or hysterectomy (n = 11). Endometrial histopathologic findings were examined. RESULTS: Overall, endometrial polyps were the most common histopathologic finding (23 of 35 patients). Endometrial cystic atrophy was uncommonly detected in patients undergoing curettage-hysteroscopy (1 of 24 patients) compared with patients undergoing hysterectomy (9 of 11 patients). No cases of endometrial cancer or hyperplasia were detected. CONCLUSIONS: Endometrial polyps were a frequent finding in tamoxifen-treated postmenopausal women who had endometrial thickness > or = 5 mm with the use of transvaginal ultrasonography. Endometrial cystic atrophy may explain "thickened endometrium" on transvaginal ultrasonography in this patient population with no evidence of endometrial polyps, hyperplasia, or adenocarcinoma after surgical evaluation.


Asunto(s)
Antineoplásicos Hormonales/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Quistes/diagnóstico por imagen , Endometrio/diagnóstico por imagen , Posmenopausia/fisiología , Tamoxifeno/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos Hormonales/uso terapéutico , Atrofia , Legrado , Endometrio/efectos de los fármacos , Endometrio/patología , Femenino , Humanos , Histerectomía , Persona de Mediana Edad , Pólipos/inducido químicamente , Pólipos/diagnóstico por imagen , Pólipos/patología , Estudios Retrospectivos , Tamoxifeno/uso terapéutico , Ultrasonografía , Enfermedades Uterinas/inducido químicamente , Enfermedades Uterinas/diagnóstico por imagen , Enfermedades Uterinas/patología
9.
Bioconjug Chem ; 9(1): 87-93, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9460550

RESUMEN

Biodistributions of two radiometal chelate conjugates of the human/murine chimeric anticarcinoembryonic antigen monoclonal antibody cT84.66 were obtained in nude mice bearing LS174T human colorectal carcinoma xenografts. Derivatives of the macrocyclic chelating agent 1,4,7,10-tetraazacyclododecane-N,N',N",N"'-tetraacetic acid (DOTA) were covalently attached to the antibody by a stable amide linkage and by a maleimidocysteineamido side chain (MC-DOTA) that has been shown to be chemically labile at physiological temperature and pH. Biodistributions of both 111In and 90Y labels were obtained in these studies. At common biodistribution time points, it was found that the 111In label had greater uptake in the liver than 90Y for both conjugates. No significant differences were found with respect to bone uptake of 90Y using either chelate. Blood curves were generally lower at comparable time points for MC-DOTA, indicative of faster clearance as compared to DOTA. Tumor uptake was high for both conjugates (57-68% ID/g at 48 h), with a longer tumor residence time in the case of the DOTA conjugate, probably a result of its longer blood circulation times. We conclude that bone uptake of 90Y would be minimal if either DOTA or MC-DOTA were used as the bifunctional chelator. This would imply preference for these macrocyclic ligands if radiation doses to the bone marrow would be considered to be dominated by skeletal uptakes. Alternatively, if bone marrow radiation dose is dominated by circulating antibody, the chemically labile linker system employed by the MC-DOTA conjugate offers the advantage of enhanced blood clearance.


Asunto(s)
Anticuerpos Monoclonales/química , Antígeno Carcinoembrionario/inmunología , Quelantes/farmacocinética , Compuestos Heterocíclicos con 1 Anillo , Compuestos Heterocíclicos/farmacocinética , Maleimidas/farmacocinética , Trasplante de Neoplasias , Animales , Médula Ósea/metabolismo , Huesos/metabolismo , Neoplasias Colorrectales/metabolismo , Estabilidad de Medicamentos , Humanos , Radioisótopos de Indio/farmacocinética , Marcaje Isotópico , Ratones , Ratones Desnudos , Distribución Tisular , Trasplante Heterólogo , Radioisótopos de Itrio/farmacocinética
10.
J Clin Oncol ; 15(8): 2882-93, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9256132

RESUMEN

PURPOSE: To examine the predictive value of tumor- and treatment-specific prognostic indicators of relapse-free survival (RFS) and overall survival (OS) in patients with high-risk breast cancer (HRBC) treated with high-dose chemotherapy (HDCT) and stem-cell rescue. PATIENTS AND METHODS: Between June 1989 and September 1994, 114 patients with HRBC (stage II with > or = 10 axillary lymph nodes involved, stage IIIA, and stage IIIB inflammatory carcinoma) received adjuvant chemotherapy followed by HDCT with etoposide, cyclophosphamide, and either doxorubicin (CAVP) or cisplatin (CCVP). Variables analyzed included stage, tumor size, number of axillary nodes involved, grade and receptor status, and types of adjuvant chemotherapy and radiation therapy and HDCT. RESULTS: With a median follow-up time of 46 months (range, 23 to 93), Kaplan-Meier estimates of 3.5-year OS for stage II, IIIA, and IIIB HRBC are 82% (95% confidence interval [CI], 67% to 97%), 79% (95% CI, 67% to 91%), and 72% (95% CI, 53% to 91%); RFS estimates are 71% (95% CI, 56% to 85%), 57% (95% CI, 43% to 72%), and 50% (95% CI, 29% to 71%) irrespective of the HDCT regimen. In univariate analysis, the risk of relapse was lower for patients with progesterone receptor (PR)-positive tumors (risk ratio [RR], 0.43; 95% CI, 0.22 to 0.81; P = .01) and higher for patients with inflammatory carcinoma (RR, 2.20; 95% CI, 1.02 to 4.76; P = .05). OS was better for patients with PR (RR, 0.16; 95% CI, 0.05 to 0.55; P = .003) and estrogen receptor (ER)-positive tumors (RR, 0.42; 95% CI, 0.17 to 1.02; P = .05); OS was worse for patients with high-grade primary tumors (RR, 4.08; 95% CI, 1.21-13.7; P = .02). In multivariate analysis, PR positivity was associated with improved RFS (P = .01) and OS (P = .001). CONCLUSION: HDCT in selected patients with HRBC is safe and warrants further evaluation. Patients with receptor-negative, high-grade, or inflammatory tumors require improvement in their therapeutic options. Better assessment of the role of HDCT awaits completion of ongoing randomized trials.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/terapia , Trasplante de Células Madre Hematopoyéticas , Adulto , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Terapia Combinada , Ciclofosfamida/administración & dosificación , Ciclofosfamida/efectos adversos , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Doxorrubicina/administración & dosificación , Doxorrubicina/efectos adversos , Etopósido/administración & dosificación , Etopósido/efectos adversos , Femenino , Humanos , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , Tasa de Supervivencia
11.
Am J Pathol ; 151(1): 161-8, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9212742

RESUMEN

Ductal carcinoma in situ (DCIS) of the breast is a heterogeneous disease clinically and biologically. The few available studies of its natural history implicate DCIS as a non-obligate precursor for invasive carcinoma. We have used fluorescence in situ hybridization (FISH) to detect gene amplification of the cell cycle regulator gene CCND1 in 88 examples of formalin-fixed, paraffin-embedded DCIS. Expression of its protein product cyclin D1 was detected by immunohistochemistry. CCND1 was amplified in 18% of DCIS cases. High grade DCIS was more likely to show amplification than low grade DCIS (32% versus 8%; P = 0.08). Gene amplification was associated with cyclin D1 protein expression (P = 0.001), although cyclin D1 was detected in cases that did not demonstrate gene amplification. Overall, cyclin D1 protein was detected in 50% of DCIS cases. Although only 2 of 23 (8%) cases of low grade DCIS had CCND1 amplification, over 50% (13/23) of these cases expressed cyclin D1 protein. Low grade DCIS had a higher mean percentage of nuclei expressing cyclin D1 than did intermediate or high grade DCIS (P = 0.007). Mechanisms other than gene amplification may be responsible for increased cyclin D1 protein in DCIS, especially in low grade DCIS. Identifying mechanisms that control cell cycle progression in DCIS may yield clues to its biological behavior.


Asunto(s)
Neoplasias de la Mama/genética , Carcinoma in Situ/genética , Carcinoma Ductal de Mama/genética , Ciclinas/biosíntesis , Ciclinas/genética , Amplificación de Genes , Proteínas Oncogénicas/biosíntesis , Proteínas Oncogénicas/genética , Análisis de Varianza , Neoplasias de la Mama/patología , Carcinoma in Situ/patología , Carcinoma Ductal de Mama/patología , Ciclina D1 , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Estudios Multicéntricos como Asunto
12.
Ann Surg Oncol ; 4(5): 403-8, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9259967

RESUMEN

BACKGROUND: Locally advanced thyroid cancer invading the tracheal cartilage represents a difficult treatment dilemma during thyroidectomy. METHODS: A retrospective chart review was performed to determine the results of laryngotracheal resection or tracheal cartilage shave with adjuvant radiotherapy in patients with locally advanced thyroid cancer invading the upper airway. RESULTS: Of 597 patients undergoing thyroidectomy for thyroid cancer, 40 were found to have laryngotracheal invasion. Thirty-five patients with superficial invasion underwent cartilage shave procedures with adjuvant radiotherapy; five with full-thickness invasion underwent radical resection, including tracheal sleeve resection (n = 3) or total laryngectomy (n = 2). Histologic subtypes included papillary (n = 32), follicular (n = 2), Hurthle cell (n = 1), medullary (n = 3), and anaplastic (n = 2). Of the cartilage shave group, 25 are currently alive with no evidence of disease at a mean follow-up of 81 months (range 1-290). Six developed isolated local/regional recurrence and were managed with total laryngectomy (n = 1), tracheal resection (n = 1), cervical lymphadenectomy (n = 1), or repeat radiotherapy (n = 3). All six patients remain free of disease at a mean follow-up of 5 years. Of those who underwent initial laryngotracheal resection, four remain free of disease at a mean follow-up of 5 years. The rates of 10-year disease-free survival and overall survival for all patients were 47.9% (95% confidence interval [CI] 24.8, 71.0) and 83.9% (95% CI 70.3, 97.5), respectively. CONCLUSIONS: These data suggest that adequate management of thyroid cancer with laryngotracheal invasion can be achieved with a more conservative surgical approach and adjuvant radiotherapy, reserving more radical resections for extensive primary lesions or locally recurrent disease.


Asunto(s)
Laringe/patología , Neoplasias de la Tiroides/cirugía , Tráquea/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Supervivencia sin Enfermedad , Femenino , Humanos , Laringectomía , Laringe/cirugía , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Neoplasias de la Tiroides/mortalidad , Neoplasias de la Tiroides/patología , Tiroidectomía , Tráquea/cirugía
13.
Blood ; 89(5): 1521-8, 1997 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-9057632

RESUMEN

We evaluated the effects of various schedules of peripheral blood stem cell (PBSC) reinfusion, granulocyte colony-stimulating factor (G-CSF) priming, and CD34+ enrichment on hematopoietic recovery in 88 patients with advanced breast cancer treated with high-dose chemotherapy, consisting of cisplatin 250 mg/m2, etoposide 60 mg/kg, and cyclophosphamide 100 mg/kg. PBSC (> or = 7.5 x 10(8) nucleated cells/kg) were collected following priming with G-CSF and were either immediately cryopreserved (48 patients; cohorts A and B) or were first processed for CD34+ enrichment (40 patients; cohorts C and D). Patients in cohorts A and C received PBSC on day 0; patients in cohorts B and D received 25% of their nucleated cells on day -2 and 75% on day 0 (split reinfusion). Patients in cohorts A, B, and C were primed with G-CSF 10 micrograms/kg, subcutaneously (SC), once a day; patients in cohort D were primed with 5 micrograms/kg G-CSF, SC, twice daily (bid). Bid administration of G-CSF yielded 2.3 to 4.7 x higher numbers of CD34+ cells in the PBSC product than the same total dose given once a day (P = .002). Reinfusion of 25% of unselected PBSC on day -2 (median, 2.26 x 10(8)/kg nucleated cells [range, 1.7 to 3.3 x 10(8)/kg]) with the remaining cells reinfused on day 0 resulted in earlier granulocyte recovery to > or = 500/microL when compared with reinfusion of all stem cells on day 0 (group B, median of 8 days [range, 7 to 11] v group A, 10 days [range, 8 to 11], P = .0003); no schedule-dependent difference was noted in reaching platelet independence (group B, 11.5 days [range, 5 to 21]; group A, 12 days [range, 8 to 24], P = not significant). Split schedule reinfusion of CD34(+)-selected PBSC did not accelerate granulocyte recovery. In groups D and C, the median number of days to granulocyte recovery was 12 (range, 8 to 22) and 11.5 (range, 9 to 13); patients became platelet independent by day 15 (range, 6 to 22) and 14 (range, 12 to 23), respectively. CD34(+)-selected PBSC rescue decreased the incidence of postreinfusion nausea, emesis, and oxygen desaturation in comparison to unselected PBSC reinfusion (P < or = .005 for each). Hematopoietic recovery may be accelerated by earlier reinfusion of approximately 2.26 x 10(8)/kg unselected nucleated cells. Earlier recovery may be triggered by components other than the progenitors included in the CD34+ cell population. Sustained hematopoietic recovery can also be achieved with CD34(+)-selected PBSC alone. Dosing of G-CSF on a bid schedule generates higher CD34+ cell yield in the leukapheresis product. Whether even earlier "sacrificial" reinfusion of approximately 2 x 10(8)/kg unselected nucleated cells concomitant with the administration of high-dose chemotherapy would reduce the duration of absolute granulocytopenia further while initiating sustained long-term hematopoietic recovery will require further investigation.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias de la Mama/terapia , Carcinoma/terapia , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas/efectos de los fármacos , Adulto , Antígenos CD34 , Recuento de Células Sanguíneas , Separación Celular , Cisplatino/administración & dosificación , Terapia Combinada , Ciclofosfamida/administración & dosificación , Etopósido/administración & dosificación , Femenino , Células Madre Hematopoyéticas/patología , Humanos , Persona de Mediana Edad
14.
Cancer ; 79(3): 595-604, 1997 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-9028373

RESUMEN

BACKGROUND: Certain strains of human papillomavirus (HPV) have been shown to be etiologically related to the development of uterine cervical and other genital cancers, but their role in the development of malignancies at other sites is less well established. Previous studies have shown HPV DNA in tumors of the head and neck, but its prevalence has varied depending on the detection methods and the types of tumor and/or tissue examined. This study was undertaken to estimate the frequency of HPV DNA in squamous cell carcinoma (SCC) at different sites of the esophagus, head and neck and to compare the clinical behavior of HPV positive and negative tumors. METHODS: DNA was extracted from frozen tissue of 167 SCCs of the esophagus, head and neck. The DNA was screened for HPV sequences by polymerase chain reaction with two sets of consensus primers, one to a conserved region in the L1 gene (MY09/ MY11) and the other to a conserved region in the E1 open reading frame (IU/IWDO). The products were run on agarose gels, detected by ethidium bromide staining, and then the gels were subjected to Southern blot analysis and hybridized with probes specific to HPV 6, 16, and 18. All tumors found to be HPV positive with the consensus primers were amplified with type specific primers, and in selected cases the presence of HPV DNA was confirmed by restriction enzyme digestion of the tumor DNA with conventional Southern blot analysis. RESULTS: Overall, HPV sequences were found in 25 of 167 tumors (15%), but HPV was detected most frequently in tumors in Waldeyer's tonsillar ring. In that area, 9 of 15 (60%) were HPV positive. No HPV DNA was detected in 11 esophageal SCCs, 7 tumors of the pharynx/hypopharynx, or 6 pyriform sinus carcinomas. HPV DNA was detected in the following tumor sites: 1 of 28 (3.6%) in the larynx, 1 of 10 (10%) in the oral cavity, 5 of 39 (12.8%) in the tongue, 2 of 15 (13.5%) in the floor of the mouth, 3 of 21 (14.3%) supraglottic, and 1 of 7 (14.3%) in the lip. A high incidence of HPV DNA was also found in metastatic tumors located in cervical lymph nodes for which no primary site was clinically identified (3 of 8, 37.5%). With respect to age, gender, and tobacco and alcohol consumption, analysis of clinical data obtained by retrospective review showed no difference between patients with HPV DNA in their tumors and those in which no HPV was detected. However, HPV positive patients had larger tumors (P = 0.09) and a higher incidence of lymph node metastasis (P = 0.003). In spite of the higher stage of disease at presentation in HPV positive patients, there was no significant difference in 3-year survival rates between HPV positive patients and HPV negative patients (43.1% vs. 48.8%, respectively). Median follow-up was 27 months. CONCLUSIONS: In the head and neck, HPV-associated SCC had site specificity with the viral DNA frequently found in tumors in Waldeyer's tonsillar ring. Patients with HPV positive tumors presented with a higher stage of disease than patients with HPV negative tumors, but there was no significant difference in the 3-year survival rates between these two groups of patients.


Asunto(s)
Carcinoma de Células Escamosas/virología , Neoplasias de Cabeza y Cuello/virología , Papillomaviridae/aislamiento & purificación , Neoplasias Tonsilares/virología , Carcinoma de Células Escamosas/secundario , Sondas de ADN , ADN Viral/aislamiento & purificación , Femenino , Neoplasias de Cabeza y Cuello/patología , Humanos , Incidencia , Metástasis Linfática , Masculino , Estadificación de Neoplasias , Papillomaviridae/genética , Infecciones por Papillomavirus/complicaciones , Reacción en Cadena de la Polimerasa , Modelos de Riesgos Proporcionales , Factores de Riesgo , Análisis de Supervivencia , Neoplasias Tonsilares/patología , Infecciones Tumorales por Virus/complicaciones
15.
J Nucl Med ; 38(12): 1951-9, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9430476

RESUMEN

UNLABELLED: Chimeric T84.66 (cT84.66) is a high-affinity (1.16 x 10[11] M[-1]) IgG1 monoclonal antibody (MAb) against carcinoembryonic antigen (CEA). This pilot trial evaluated the tumor-targeting properties, biodistribution, pharmacokinetics and immunogenicity of 111In-labeled cT84.66. METHODS: Patients with CEA-producing metastatic malignancies were administered a single intravenous dose of 5 mCi 111In-diethylenetriaminepentaacetic acid-cT84.66. Serial blood samples, 24-hr urine collections and nuclear images were collected up to 7 days postinfusion. Human antichimeric antibody response was assessed up to 6 mo postinfusion. RESULTS: Imaging of at least one known tumor site was observed in 14 of 15 (93%) patients. Seventy-four lesions were analyzed with an imaging sensitivity rate of 45.1% and a positive predictive value of 94.1%. In one patient, two additional bone metastases developed within 6 mo of antibody administration at sites initially felt to be falsely positive on scan. One patient developed a human antichimeric antibody response predominantly to the murine portion of the antibody. The antibody cleared serum with a median T(1/2alpha) of 6.53 hr and a T(1/2beta) of 90.87 hr. Interpatient variations in serum clearance rates were observed and were secondary to differences in clearance and metabolic rates of antibody-antigen complexes by the liver. One patient demonstrated very rapid clearance of antibody by the liver, which compromised antibody localization to the primary tumor. Antibody uptake in primary and metastatic tumors ranged from 0.5% to 10.5% injected dose/kg, resulting in estimated radiation doses ranging from 0.97 to 21.3 cGy/mCi 90Y. Antibody uptake in regional lymph nodes ranged from 1.3% to 377% injected dose/kg, resulting in estimated radiation doses ranging from 2.0 to 617 cGy/mCi 90Y. CONCLUSION: Chimeric T84.66 demonstrated tumor targeting that was comparable to that of other radiolabeled intact anti-CEA Mabs. Its immunogenicity after single administration was lower than murine Mabs. These properties make cT84.66 or a lower molecular weight derivative attractive for further evaluation as an imaging agent. These same properties also make it appropriate for future evaluation in Phase I therapy trials. Finally, a wide variation in the rate of antibody clearance was observed, with one patient demonstrating very slow clearance, resulting in the highest estimated marrow dose of the group, and one patient demonstrating unusually rapid clearance, resulting in poor antibody localization to tumor. Data from this study suggest that serum CEA levels, antibody-antigen complex clearance and, therefore, antibody clearance are influenced by both the production and clearance rates of CEA. This underscores the need to further identify, characterize and understand those factors that influence the biodistribution and clearance of radiolabeled anti-CEA antibodies to allow for better selection of patients for therapy and rational planning of radioimmunotherapy.


Asunto(s)
Antígeno Carcinoembrionario/inmunología , Radioisótopos de Indio/uso terapéutico , Radioinmunodetección , Radioinmunoterapia , Adulto , Anciano , Animales , Femenino , Humanos , Radioisótopos de Indio/farmacocinética , Masculino , Ratones , Persona de Mediana Edad , Proyectos Piloto , Valor Predictivo de las Pruebas , Proteínas Recombinantes de Fusión/farmacocinética , Proteínas Recombinantes de Fusión/uso terapéutico , Sensibilidad y Especificidad , Distribución Tisular , Radioisótopos de Itrio/farmacocinética , Radioisótopos de Itrio/uso terapéutico
16.
J Nucl Med ; 38(12): 1959-66, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9430477

RESUMEN

UNLABELLED: The objective of this article was to model pharmacokinetic data from clinical diagnostic studies involving the 111In-labeled monoclonal antibody (MAb) chimeric T84.66, against carcinoembryonic antigen. Model-derived results based on the 111In-MAb blood, urine and digital imaging data were used to predict 90Y-MAb absorbed radiation doses and to guide treatment planning for future therapy trials. Fifteen patients with at least one carcinoembryonic antigen-positive lesion were evaluated. We report the kinetic parameter estimates and absorbed 111In-MAb dose and projected 90Y-MAb doses for each patient as well as describe our approach and rationale for modeling an extensive set of pharmacokinetic data. METHODS: The ADAPT II software package was used to create three- and five-compartment models of uptake against time in the patient population. The "best-fit" model was identified using ordinary least squares. Areas under the curve were calculated using the modeled curves and input into MIRDOSE3 to estimate absorbed radiation doses for each patient. RESULTS: A five-compartment model best described the liver, whole body, blood and urine data for a subcohort of nine patients with digital imaging data. A three-compartment model best described the blood and urine data for all 15 clinical patients accrued in the clinical trial. For the subcohort, the largest projected 90Y-MAb doses were delivered to the liver (mean, 24.78 rad/mCi; range, 15.02-37.07 rad/mCi), with red marrow estimates on the order of 3.32 rad/mCi (range, 1.24-5.55) of 90Y. Corresponding estimates for the 111In-MAb were 3.18 (range, 2.09-4.43) and 0.55 (range, 0.34-0.74), respectively. CONCLUSION: The three- and five-compartment models presented here were successfully used to represent the blood, urine and imaging data. This was evidenced by the small standard errors for the kinetic parameter estimates and R2 values close to 1. As planned future therapeutic trials will involve stem cell support to alleviate hematological toxicities, the development of an approach for estimating doses to other major organs is crucial.


Asunto(s)
Antígeno Carcinoembrionario/inmunología , Radioisótopos de Indio/farmacocinética , Radioisótopos de Indio/uso terapéutico , Radioinmunodetección , Radioinmunoterapia , Radioisótopos de Itrio/farmacocinética , Radioisótopos de Itrio/uso terapéutico , Adulto , Anciano , Animales , Femenino , Humanos , Masculino , Ratones , Persona de Mediana Edad , Modelos Teóricos , Proyectos Piloto , Dosis de Radiación , Proteínas Recombinantes de Fusión/farmacocinética , Proteínas Recombinantes de Fusión/uso terapéutico , Distribución Tisular
17.
J Nucl Med Technol ; 25(4): 264-8, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9438927

RESUMEN

OBJECTIVE: An approach for estimating organ residence times (tau) and their errors in patient internal emitter radiation dosage calculations has been determined. METHODS: Using a modeling algorithm and its associated parameters, chimeric anti-CEA monoclonal antibody (cT84.66) patient organ uptake data and residence times of source organ activity were calculated. Through the covariance matrix of the model's parameters and subsequent Monte Carlo simulations, errors in organ residence time (gamma tau) also were estimated RESULTS: These relative tau errors were found to be model-dependent; increasing as the number of organs being simultaneously modeled in a set of two patients being considered for 90Y-cT84.66 radioimmunotherapy. CONCLUSION: Use of modeling and Monte Carlo methods provide a general, direct procedure for calculating the degree of accuracy of activity integrals and other mathematical functions of kinetic variables.


Asunto(s)
Radioinmunoterapia , Algoritmos , Humanos , Radioisótopos de Indio/uso terapéutico , Método de Montecarlo , Dosificación Radioterapéutica , Radioisótopos de Itrio/uso terapéutico
18.
Ann Surg Oncol ; 3(4): 406-10, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8790855

RESUMEN

BACKGROUND: Surgical oncology as a distinct field of expertise is fairly young. The current study was designed to gain a better understanding of the attitude of practicing physicians toward the field of surgical oncology. METHODS: Three hundred twenty-seven physicians in the San Gabriel Valley (a suburban area adjacent to Los Angeles) responded to an anonymous survey of opinions regarding surgical oncology. Responses were placed into a computerized database. RESULTS: Of those responding, 179 were primary care physicians, 52 were general surgeons, 78 were gynecologists, and 18 were medical oncologists. Overall, 89% of physicians were familiar with the field of surgical oncology, but only 47% had ever heard of The Society of Surgical Oncology (SSO). Ninety-four percent of the respondents felt that a surgical oncologist should care for patients with complex cancer, and 63% of respondents felt that surgical oncologists should care only for patients with complex cancer. Familiarity with the field of surgical oncology and with the SSO correlated with the percentage of the physicians practice that was cancer related. Only 22% of physicians felt that the field of surgical oncology is redundant to the general surgical specialties. CONCLUSIONS: Results of the survey indicate that there is considerable recognition of the unique expertise of the surgical oncologist by the medical community. Unfortunately, many physicians are not familiar with the SSO. Educating physicians in the community about the SSO may help to further expand the role of the surgical oncologist in the care of the patient with cancer, standardize the expectations of the skills and training of a surgical oncologist, and set a benchmark for the surgical subspecialty.


Asunto(s)
Actitud del Personal de Salud , Cirugía General , Oncología Médica , Médicos/psicología , Humanos , Sociedades Médicas
19.
Cancer Lett ; 101(1): 59-66, 1996 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-8625283

RESUMEN

We evaluated the histopathologic changes of the uterine epithelium in 73 breast cancer patients with tamoxifen stratified by menopausal status. Clinicopathologic data at the time of breast cancer diagnosis and endometrial sampling were analyzed and compared with 122 breast cancer patients not receiving the drug. The incidence of endocervical and/or endometrial polyps was increased in tamoxifen-treated postmenopausal patients compared with untreated patients, 43% (25 of 58) and 24% (16 of 68), respectively (odds ratio=2.46, P=0.02). In contrast, there was no increase in polyps in premenopausal tamoxifen-treated patients. This finding suggests that the effects of tamoxifen on the endometrium may vary with menopausal status.


Asunto(s)
Adenocarcinoma/inducido químicamente , Antineoplásicos Hormonales/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Menopausia , Pólipos/inducido químicamente , Tamoxifeno/efectos adversos , Neoplasias Uterinas/inducido químicamente , Útero/efectos de los fármacos , Estudios Transversales , Hiperplasia Endometrial/inducido químicamente , Epitelio/efectos de los fármacos , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Útero/patología , Útero/cirugía
20.
Immunotechnology ; 2(1): 21-36, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9373325

RESUMEN

BACKGROUND: Genetic engineering can produce novel antibody fragments with improved properties for applications such as tumor targeting in vivo. OBJECTIVES: To produce stable monomeric (27 kDa) and dimeric (55 kDa) forms of a single-chain Fv (scFv) from the anti-carcinoembryonic antigen (anti-CEA) antibody T84.66, and assess the targeting and biodistribution properties in an animal model. STUDY DESIGN: ScFv were constructed with either a 28 or 14 amino acid connecting peptide and expressed by secretion from E. coli. Following affinity purification, proteins were characterized by gel electrophoresis and mass spectrometry. Binding properties were assessed by size exclusion HPLC after incubation with antigen, and affinities determined by surface plasmon resonance. The shorter linker favored formation of dimers (and higher multimers) which showed unusual stability. ScFv were radiolabeled with 125I for tumor targeting and biodistribution studies of monomeric or dimeric forms were conducted in athymic mice bearing LS174T human colorectal carcinoma xenografts. RESULTS: 125I-scFv monomers and dimers targeted exhibited rapid clearance kinetics in tumor-bearing mice. Nevertheless, the anti-CEA scFvs targeted very well to xenografts, leading to high tumor: normal organ ratios (greater than 20:1 at 24 h) for both forms. Tumor localization of the non-covalent dimers was much higher than monomers, reaching 10-15% injected dose per gram at 1 h. CONCLUSION: Non-covalent dimers of scFv (also known as diabodies) are stable, easy to produce and show excellent targeting as compared to monomeric scFv, probably due to increased mass and valency.


Asunto(s)
Anticuerpos Antineoplásicos/inmunología , Antígeno Carcinoembrionario/inmunología , Carcinoma/inmunología , Fragmentos de Inmunoglobulinas/inmunología , Animales , Afinidad de Anticuerpos , Antígenos de Neoplasias/inmunología , Antígenos de Neoplasias/metabolismo , Carcinoma/metabolismo , Cromatografía de Afinidad , Cromatografía Líquida de Alta Presión , Clonación Molecular , Neoplasias Colorrectales/inmunología , Electroforesis en Gel de Poliacrilamida , Femenino , Expresión Génica , Humanos , Fragmentos de Inmunoglobulinas/genética , Fragmentos de Inmunoglobulinas/aislamiento & purificación , Espectrometría de Masas , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Péptidos/inmunología , Péptidos/aislamiento & purificación
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...