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1.
J Physiol Pharmacol ; 60 Suppl 5: 31-6, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20134035

RESUMO

Moderate physical activity increases antioxidant defenses, whereas intensive activity is associated with oxidative stress. In this study we investigated the expression of superoxide dismutase (Cu,Zn-SOD), a major antioxidant defense enzyme, and that of the proteolytic enzyme matrix metalloproteinase-2 (MMP-2) in exercising muscle tissue. Treadmill running was used as a model to investigate the mechanism involved in muscle use and over use. Sprague-Dawley female rats (4 months old) were randomly assigned to 3 groups: running group I, trained at a slow speed (18 m/min; approximately 50% VO(2)), running group II, trained at a very fast speed (32 m/min; approximately 75% VO(2)), for 3 weeks, and group III - control, non-running group. Cu,Zn-SOD was measured spectrophotometrically at 320 nm by assessing the inhibition of cytochrome c reduction by xanthine oxidase. MMP-2 levels of protein and mRNA were assessed in the diaphragm by Western blotting and by reverse transcriptase-polymerase chain reaction, respectively. We found that Cu,Zn-SOD level significantly decreased in the crural diaphragm muscle of rats three weeks after fast speed running, whereas it remained unchanged in the sternal diaphragm muscle three weeks after slow speed running. The expression of MMP-2 increased in both fast and slow running groups; however, it was particularly prominent in the fast twitch muscle fibers type IIb. We conclude that the crural diaphragm muscle, which contains significantly more type IIb fibers, was more affected following fast speed running than the sternal/costal diaphragm muscles, which have an equal distribution of slow twitch (type I) and fast twitch (type IIb) muscle fibers.


Assuntos
Diafragma/enzimologia , Metaloproteinase 2 da Matriz/biossíntese , Superóxido Dismutase/biossíntese , Fatores Etários , Animais , Diafragma/crescimento & desenvolvimento , Teste de Esforço/métodos , Feminino , Regulação Enzimológica da Expressão Gênica , Metaloproteinase 2 da Matriz/genética , Condicionamento Físico Animal/métodos , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/genética , Superóxido Dismutase-1
2.
Int J Radiat Oncol Biol Phys ; 53(1): 58-66, 2002 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-12007942

RESUMO

PURPOSE: To conduct a Phase II one-arm study to evaluate the long-term efficacy and safety of accelerated fractionated radiotherapy combined with i.v. carboplatin for patients with previously untreated anaplastic gliomas. METHODS AND MATERIALS: Between 1988 and 1992, 90 patients received 1.9-2.0-Gy radiation 3 times a day with 2-h infusions of 33 g/m(2) carboplatin for two 5-day cycles separated by 2 weeks. After radiotherapy, patients received procarbazine, lomustine (CCNU), and vincristine (PCV) for 1 year or until the tumor progressed. RESULTS: Ninety patients were evaluable for analysis. Histologically, 69 had anaplastic astrocytoma; 14, anaplastic oligoastrocytoma; and 7, anaplastic oligodendroglioma. Gross total resection was performed in 20 (22%), subtotal resection in 45 (50%), and biopsy in 25 (28%); reoperation (total or subtotal resection) was performed in 50 (56%) patients. A multivariate analysis showed that a younger age (p = 0.026), Karnofsky performance score (KPS; p = 0.009), and brain necrosis (p = 0.0002) were predictive of a better survival. Results from analysis of extent of surgery (biopsy, subtotal resection, gross total resection) approached significance (p = 0.058). Radiation dose, irradiated tumor volume, and techniques used (boost and fields) were not significant variables. The median survival (MS) of all anaplastic glioma patients was 28.1 months; for anaplastic astrocytoma patients, MS was 28.7 months and 40.8 months for the combined anaplastic oligodendroglioma/oligoastrocytoma patients. Long-term survival occurred in 25% of anaplastic glioma patients who were alive 8.6 years after treatment was initiated. Treatment-induced necrosis was documented by surgery or autopsy in 19 (21%) patients; 21 (23%) had a mixed pattern of necrosis and tumor; and an additional 13 (14%) patients who did not have surgical or autopsy demonstration of predominant radiation necrosis had magnetic resonance imaging (MRI) evidence of radiation necrosis. Serious clinical neurologic deterioration and/or dementia requiring full-time caregiver attention were observed in 9 (10%) patients. CONCLUSION: When comparable selection criteria are applied, the rate of MS in this study is inferior to results attainable with current radiation and chemotherapy approaches, although the rates of long-term survival are comparable. Theoretically, patients failing therapy and dying earlier than anticipated may be because of excessive central nervous system (CNS) toxicity resulting from the combination of accelerated fractionated irradiation, intensive carboplatin chemotherapy before each radiation fraction, and postirradiation PCV chemotherapy. On the other hand, patients with treatment-induced necrosis survived significantly longer than patients who did not demonstrate MRI or histologic evidence of necrosis (MS, 106 months vs. 18-33 months).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Astrocitoma/tratamento farmacológico , Astrocitoma/radioterapia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Oligodendroglioma/tratamento farmacológico , Oligodendroglioma/radioterapia , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Carboplatina/uso terapêutico , Terapia Combinada , Fracionamento da Dose de Radiação , Feminino , Humanos , Lomustina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Oligodendroglioma/patologia , Procarbazina/administração & dosagem , Análise de Sobrevida , Vincristina/administração & dosagem
3.
Int J Oncol ; 18(4): 689-95, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11251162

RESUMO

The clavicle is frequently incorporated into the radiation field in the treatment of malignant tumors located in the head and neck. From 1954 to 1995, 499 pediatric patients were treated with moderate to high-dose radiation therapy to the head and neck at the University of Texas M.D. Anderson Cancer Center. The medical records of 312 of these patients were available and were reviewed. The period of observation ranged from 5 to 30 years. Five late radiation-induced abnormalities of the clavicle were encountered: osteosarcoma; osteochondroma; malignant fibrous histiocytoma; radionecrosis and impaired healing following trauma and radionecrosis and lysis. The doses of radiation therapy which induced the abnormalities varied from 35 to 60.5 Gy (median 34.75 Gy). The interval from radiation therapy to discovery of the complications varied from 6 to 11 years. Two patients died: one from malignant fibrous histiocytoma and another from a radiation-induced meningioma of the brain (which accompanied radionecrosis of the clavicle). We conclude that the incidence of radiation-induced abnormalities of the clavicle in pediatric long-term survivors is low (1.5%). However, some of the late sequela are potentially fatal. The clavicle should be considered a vulnerable bone to radiation therapy and should be monitored in long-term survivors of childhood cancer. The experience is compared to radiation-induced abnormalities recorded in the literature.


Assuntos
Neoplasias Ósseas/etiologia , Clavícula/efeitos da radiação , Neoplasias de Cabeça e Pescoço/radioterapia , Histiocitoma Fibroso Benigno/etiologia , Neoplasias Induzidas por Radiação/etiologia , Osteocondroma/etiologia , Osteossarcoma/etiologia , Adolescente , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/patologia , Criança , Pré-Escolar , Neoplasias de Cabeça e Pescoço/patologia , Histiocitoma Fibroso Benigno/diagnóstico por imagem , Histiocitoma Fibroso Benigno/patologia , Humanos , Masculino , Neoplasias Induzidas por Radiação/patologia , Osteocondroma/diagnóstico por imagem , Osteocondroma/patologia , Osteonecrose/diagnóstico por imagem , Osteonecrose/etiologia , Osteonecrose/patologia , Osteossarcoma/diagnóstico por imagem , Osteossarcoma/patologia , Radiografia , Radioterapia/efeitos adversos , Estudos Retrospectivos , Fatores de Risco
4.
Radiology ; 217(2): 377-84, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11058631

RESUMO

PURPOSE: To describe both the common and less frequently encountered magnetic resonance (MR) imaging features of radiation therapy- and chemotherapy-induced brain injury, with particular emphasis on radiation necrosis. MATERIALS AND METHODS: A cohort of 148 adult patients underwent surgical resection of malignant brain (glial) tumors and were subsequently entered into a research protocol that consisted of accelerated radiation therapy with carboplatin followed by chemotherapy with procarbazine, lomustine, and vincristine. Patients typically underwent sequential MR imaging at 6-8-week intervals during the 1st year and at 3-6-month intervals during subsequent years. In all patients, histopathologic confirmation of lesion composition was performed by board-certified neuropathologists. RESULTS: The patients exhibited different types of MR imaging-detected abnormalities of the brain: pure radiation necrosis in 20 patients, a mixture of predominantly radiation necrosis with limited recurrent and/or residual tumor (less than 20% of resected tissue) in 16 patients, radiation necrosis of the cranial nerves and/or their pathways in two patients, radiation-induced enhancement of the white matter in 52 patients, and radiation-induced enhancement of the cortex in nine patients. CONCLUSION: The frequent diagnostic dilemma of recurrent neoplasm versus radiation necrosis is addressed in this study through a description of the varying spatial and temporal patterns of radiation necrosis at MR imaging.


Assuntos
Antineoplásicos/efeitos adversos , Neoplasias Encefálicas/terapia , Encéfalo/patologia , Glioma/terapia , Imageamento por Ressonância Magnética , Lesões por Radiação/diagnóstico , Adolescente , Adulto , Idoso , Encéfalo/efeitos dos fármacos , Encéfalo/efeitos da radiação , Neoplasias Encefálicas/diagnóstico , Diagnóstico Diferencial , Feminino , Glioma/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Necrose , Recidiva Local de Neoplasia
5.
Int J Cancer ; 90(3): 157-62, 2000 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-10900428

RESUMO

This study was conducted to determine prognostic factors for tumor response and patient survival after stereotactic radiosurgery (SRS) for brain metastasis. Eighty-four patients with brain metastasis underwent SRS at a single institution. After fixation of the head with a stereotactic frame, computed tomography treatment planning was performed. The metastatic lesion was treated with multiple arcs to a median dose of 19 Gy. Forty-seven patients (56%) had a solitary brain lesion. Fifty-nine patients (70%) had evidence of extracranial disease at the time of SRS. The median survival duration from SRS was 7 months. Sixty-three percent of the patients had an objective radiographic response to SRS, which in turn was associated with superior central nervous system control. Age, collimator size, number of arcs, tumor location, and histology did not influence objective response rates. Patients who had a solitary lesion or who received treatment within 2 weeks after diagnosis were more likely to have an objective response than were those who did not (P < 0.05). Progressive brain disease accounted for 37% of the deaths. Nineteen patients (23%) had an in-field relapse. Four severe complications were attributed to SRS. This study confirms the role of SRS as an acceptable treatment option for patients with solitary or limited brain metastases. Int. J. Cancer (Radiat. Oncol. Invest.) 90, 157-162 (2000).


Assuntos
Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Radiocirurgia , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida
6.
Int J Radiat Oncol Biol Phys ; 45(1): 127-35, 1999 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10477016

RESUMO

PURPOSE: To conduct a Phase II study to evaluate the long-term efficacy and safety of high-dose 5'-bromodeoxyuridine (BrdU) and accelerated radiotherapy followed by procarbazine, lomustine (CCNU), and vincristine (PCV) chemotherapy in patients with glioblastoma multiforme. METHODS AND MATERIALS: Between 1994 and 1996, 88 patients were enrolled to receive 1.9 Gy of radiation three times a day for two 5-day cycles separated by 2 weeks; each 5-day cycle was preceded by a continuous 96-hour infusion of BrdU at a dose of 2.1 g/m2/day. After radiotherapy, patients received PCV chemotherapy. RESULTS: Median survival for all 88 patients was 50 weeks. Seventy (79.5 %) received one or more courses of PCV; their median survival was 57 weeks. Covariates predictive of improved survival were gross total versus subtotal resection or biopsy (p = 0.0048) and radiation dose > or = 56 Gy (p = 0.019). While receiving BrdU, 47 patients (53%) suffered grade 3 or 4 thrombocytopenia or leukopenia; 22 patients (25%) suffered grade 3 or 4 dermatologic toxicity. CONCLUSION: Survival was not extended in patients with glioblastoma or gliosarcoma who received BrdU at the dose and administration schedule used in this study. The BrdU dose used in this study resulted in substantial myelosuppressive and dermatologic toxicity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Glioblastoma/tratamento farmacológico , Glioblastoma/radioterapia , Radiossensibilizantes/administração & dosagem , Adulto , Idoso , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Bromodesoxiuridina/administração & dosagem , Bromodesoxiuridina/efeitos adversos , Cognição/efeitos dos fármacos , Cognição/efeitos da radiação , Terapia Combinada , Progressão da Doença , Intervalo Livre de Doença , Feminino , Glioblastoma/patologia , Glioblastoma/cirurgia , Humanos , Lomustina/administração & dosagem , Lomustina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Procarbazina/administração & dosagem , Procarbazina/efeitos adversos , Radiossensibilizantes/efeitos adversos , Reoperação , Vincristina/administração & dosagem , Vincristina/efeitos adversos
7.
Int J Oncol ; 14(6): 1039-43, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10339654

RESUMO

Eighty-five patients (37 female, 48 male; median age 14 years) with non-metastatic Ewing's sarcoma received definitive treatment at the University of Texas M.D. Anderson Cancer Center between 1969 and 1988. Multidisciplinary therapy was administered as follows: combination chemotherapy (CC) and local radiotherapy (XRT): 65 patients; CC, XRT and surgery, 19 patients; and XRT and surgery, 1 patient. This permitted a 10-20 year follow-up for 75% of our patients. The overall survival at 5 and 10-20 years was 46.1%, and 37.2%, respectively. At 5 years, 80.5% of live patients had control of local disease. The influence of sex, age, ethnicity, primary site, size, lactic dehydrogenase (LDH) level, presence or absence of systemic symptoms, and XRT dose (<60 Gy and

Assuntos
Neoplasias Ósseas/cirurgia , Sarcoma de Ewing/cirurgia , Adolescente , Adulto , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/radioterapia , Neoplasias Ósseas/secundário , Criança , Pré-Escolar , Terapia Combinada , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Sarcoma de Ewing/tratamento farmacológico , Sarcoma de Ewing/radioterapia , Sarcoma de Ewing/secundário
8.
Cancer ; 83(10): 2181-4, 1998 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-9827723

RESUMO

BACKGROUND: The prognosis of patients with brain metastasis as the only manifestation of an undetected primary tumor generally is considered to be poor. Therefore, most treatment is palliative. The authors reviewed the clinical outcomes and treatment results of patients presenting with brain metastasis from an undetected primary tumor at The University of Texas M. D. Anderson Cancer Center. METHODS: Between 1977-1996, 220 patients were referred to the study department for the treatment of brain metastasis from an undetected primary tumor. The patients' records were reviewed to identify those for whom brain metastasis was the only manifestation of the primary tumor. The majority of patients were excluded from the current analysis because extracranial metastasis also were present. Thirty-nine patients qualified for this retrospective review. The level of neurosurgical excision varied, but all patients received radiotherapy. Tumor control in the brain and survival were analyzed by various tumor-related and treatment-related factors. RESULTS: In 31 patients, the brain metastasis were adenocarcinomas, whereas the remaining patients had tumors of various other histologies. In 12 patients, the primary tumor eventually was found, most commonly in the lung. The median survival time for all patients was 13.4 months. Overall survival rates (OS) at 1, 3, and 5 years were 56%, 19%, and 15%, respectively. Intracranial disease control was 72% at 5 years. Patients who received gross total resection (GTR) and radiotherapy had significantly better OS than patients who received radiotherapy alone. The OS of patients whose primary tumor was identified was similar to that of patients in whom the primary tumor remained occult. CONCLUSIONS: Brain metastasis as the only manifestation of an unknown primary tumor is a distinct clinical entity. The prognosis for patients with this presentation is better than that of patients with brain metastasis in general. Although the majority of patients die of extracranial disease, a few will achieve long term survival. Treatment to the brain is effective in controlling local disease; aggressive treatment with GTR and radiotherapy is recommended.


Assuntos
Neoplasias Encefálicas/secundário , Neoplasias Primárias Desconhecidas/patologia , Adenocarcinoma/diagnóstico , Adenocarcinoma/radioterapia , Adenocarcinoma/secundário , Adenocarcinoma/cirurgia , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Carcinoma de Células Pequenas/diagnóstico , Carcinoma de Células Pequenas/radioterapia , Carcinoma de Células Pequenas/secundário , Carcinoma de Células Pequenas/cirurgia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
9.
Int J Radiat Oncol Biol Phys ; 41(3): 647-50, 1998 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-9635715

RESUMO

PURPOSE: To review the long-term clinical effects of unilateral kidney irradiation on overall renal function and blood pressure in patients with gastric lymphoma. METHODS AND MATERIALS: In the study were 27 patients with Stage I or II gastric lymphoma who had undergone irradiation of at least 24 Gy to > or = 1/3 of the left kidney. They include 16 women and 11 men, aged 31 to 77, with a mean age of 57.6 years (median 56). Fifteen patients had Stage I and 12 had Stage II disease. In 13 patients the whole kidney had been irradiated, and 14 had had partial kidney irradiation, at doses ranging between 24 and 40.5 Gy. All patients received combined chemotherapy with various drugs: all patients received corticosteroids, and five received cis-platinum. Their follow-up ranged between 0.7 and 7.8 years (mean 3.4 years). Data on possible effects of the treatment on blood pressure, renal function as assessed by blood urea and creatinine, and kidney shrinkage as seen by serial computed tomography scanning were collected on all patients. RESULTS: Three patients had persistent, mild elevations of urea and creatinine levels, which did not require special treatment. All three also received cis-platinum. Ipsilateral kidney shrinkage was evident in most patients. In 19 patients the craniocaudal measurement of the kidney shrank by > or = 1.6 cm. Shrinkage in other dimensions was also evident. The degree of atrophy was related to the volume of kidney irradiated. Only two patients developed hypertension, both at a low level of 150/90; one patient had had 40 Gy to the whole kidney, the other 40 Gy to half the kidney. Neither patient had elevated urea or creatinine. CONCLUSIONS: Notwithstanding the shrinkage to the irradiated part of the kidney, the treatment did not lead to clinically significant hypertension or renal dysfunction. The administration of cis-platinum to patients with gastric lymphoma that requires kidney irradiation should be further evaluated.


Assuntos
Rim/efeitos da radiação , Leucemia Linfocítica Crônica de Células B/radioterapia , Linfoma de Zona Marginal Tipo Células B/radioterapia , Linfoma Difuso de Grandes Células B/radioterapia , Neoplasias Gástricas/radioterapia , Adulto , Idoso , Feminino , Humanos , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade
11.
Int J Radiat Oncol Biol Phys ; 37(4): 753-9, 1997 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-9128947

RESUMO

PURPOSE: Approximately 10% of patients with metastatic renal cell carcinoma are diagnosed with brain metastases. Most of these patients receive palliative radiotherapy and die of progressive brain metastatic disease. This retrospective study examines the M. D. Anderson Cancer Center experience with such patients who received only whole brain radiation therapy (WBRT). METHODS AND MATERIALS: Records of 200 patients with brain metastases from renal carcinoma who were treated at M. D. Anderson Cancer Center between 1976 and 1993 were reviewed. Of these patients, 119 received WBRT only and constitute the basis of this study. Different prognostic factors were analyzed. RESULTS: Overall median survival time from diagnosis of the brain metastases was 4.4 months. Multiple brain tumors were treated in 70 patients (58.8%) who had a survival of 3.0 months compared with 4.4 months for patients having a single brain metastasis (p = 0.043). Among 117 patients the causes of death were neurologic in 90 (76%), systemic cancer in 19 (16%), and unknown in 9 (8%). Survival rates at 6 months, 1 year, and 2 years, were 33.6, 16.8, and 5.9%, respectively. Patients in whom brain metastases were diagnosed synchronously with a renal primary (n = 24) had a median survival time of 3.4 months compared with 3.2 months for those 95 who were diagnosed metachronously (p < 0.79, NS). In the Cox multivariate analysis of 13 possible prognostic factors, only a single brain metastasis (p = 0.0329), lack of distant metastases at the time of diagnosis (p = 0.0056), and tumor diameter < or = 2 cm (p < 0.0016) were statistically significant. CONCLUSION: These unsatisfactory results with WBRT suggest that more aggressive approaches, such as surgery or radiosurgery should be applied whenever possible.


Assuntos
Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Carcinoma de Células Renais/radioterapia , Carcinoma de Células Renais/secundário , Neoplasias Renais/patologia , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/patologia , Irradiação Craniana , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos , Análise de Sobrevida
12.
Int J Radiat Oncol Biol Phys ; 37(3): 679-88, 1997 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9112467

RESUMO

PURPOSE: A prototype Miniature Multi-Leaf Collimator (MMLC) designed specifically for radiosurgery and small field radiotherapy has been fabricated and evaluated at the University of Texas M. D. Anderson Cancer Center (UTMDACC). This work demonstrates the advantages of a computer-controlled MMLC vs. conventional circular collimation for the treatment of an irregularly shaped target volume in the brain. METHODS AND MATERIALS: Two patient treatments were selected for this comparison from 38 intracranial tumors treated with radiosurgery at UTMDACC from 8/6/91 to 5/10/94. Target contours and critical structures defined for one of the patients was used to create a simulated target volume and critical structures in a spherical head phantom. Computer simulations were performed using traditional single isocenter treatment with a circular collimator for a set of six arcs. The same arc paths were used to compute the dose distribution for the MMLC and conformed beam geometries were defined using a three-dimensional (3D) treatment planning system with beam's eye view capabilities. Then, the calculated dose distribution for a single isocenter, conformal treatment was delivered to the spherical head phantom under static conditions by shaping the MMLC to conform the target volume shape projected as a function of couch rotation and gantry angle. Planar dose distributions through the target volume were measured using therapy verification film located in the phantom. The measurements were used to verify that the 3D treatment planning system was capable of simulating the MMLC technique. For the second patient with a peanut-shaped tumor, the 3D treatment planning calculations were used to compare dose distributions for the MMLC and for traditional single and multiple isocenter treatments using circular collimators. The resulting integral dose-volume histograms (DVHs) for the target volume, normal brain, and critical structures for the three treatment techniques were compared. RESULTS: (a) Analysis of the film dosimetry data exemplified the degree of conformation of the high-dose region to the target shape that is possible with a computer-controlled MMLC. (b) Comparison of measured and calculated dose distributions indicates that the 3D treatment planning system can simulate the MMLC treatment. (c) Comparison of DVHs from the single isocenter MMLC and circular collimator treatments shows similar coverage of the target volume with increased dose to the brain for circular collimation (4). Comparison of DVHs from the single isocenter MMLC with the multiple isocenter circular collimator treatment approach shows a more inhomogeneous dose distribution through the target volume and increased dose to the brain for the latter. CONCLUSION: Dosimetry data for single isocenter treatments using computer-controlled field shaping with a MMLC demonstrate the ability to conform the dose distribution to an irregularly shaped target volume. DVHs validated that the single isocenter MMLC treatment is preferable to both single and multiple isocenter, circular collimator treatment because it provides a more uniform dose distribution to an irregularly shaped target volume and reduces the dose to surrounding brain tissue for the example cases.


Assuntos
Adenocarcinoma/cirurgia , Neoplasias Encefálicas/cirurgia , Seio Cavernoso/cirurgia , Simulação por Computador , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Neoplasias Induzidas por Radiação/cirurgia , Segunda Neoplasia Primária/cirurgia , Radiocirurgia/instrumentação , Terapia Assistida por Computador/instrumentação , Adenocarcinoma/secundário , Neoplasias Encefálicas/secundário , Neoplasias da Mama/patologia , Desenho de Equipamento , Feminino , Humanos , Dosagem Radioterapêutica , Rabdomiossarcoma Embrionário/radioterapia , Neoplasias Cranianas/radioterapia
13.
J Neurooncol ; 29(3): 261-7, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8858532

RESUMO

Because of a substantial overall recurrence rate of meningiomas, the role of surgery as the sole treatment for every case must be evaluated. Also, occasionally, the patient's age and/or the location of the tumor precludes considering him/her as a candidate for surgery. In these instances, radiotherapy or radiosurgery may be advisable. The article presents two cases treated at M.D. Anderson Cancer Center, those of a 65-year-old male with a tumor in the left temporal lobe and 74-year-old female with a tumor in the right petroclival region. It also reviews the roles that radiotherapy plays in treating patients with meningiomas. Retrospective analyses of outcomes provide ample evidence that conventional radiation after incomplete resection reduces the incidence of progression of tumor over a long period. Information on patients who have had only external radiation is meager, since most patients have at least a partial resection. Complete resection for benign meningiomas is sufficient. For malignant meningiomas, adjuvant radiation should be administered, regardless of the extent of surgical excision. When surgery poses a high risk of morbidity or mortality, radiation therapy and radiosurgery are promising alternatives.


Assuntos
Neoplasias Meníngeas/radioterapia , Meningioma/radioterapia , Idoso , Terapia Combinada , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/cirurgia , Meningioma/diagnóstico , Meningioma/cirurgia
14.
Int J Radiat Oncol Biol Phys ; 33(2): 357-64, 1995 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-7673023

RESUMO

PURPOSE: To conduct a Phase II one-arm study to evaluate the long-term efficacy and safety of accelerated fractionated radiotherapy combined with intravenous carboplatin for patients with previously untreated glioblastoma multiforme tumors. METHODS AND MATERIALS: Between 1988 and 1992, 83 patients received 1.9-2.0 Gy radiation three times a day with 2-h infusions of 33 mg/m2 carboplatin for two 5-day cycles separated by 2 weeks; following radiotherapy, patients received procarbazine, lomustine (CCNU), and vincristine (PCV) for 1 year or until tumor progressed. RESULTS: Eighty-three patients were evaluable for analysis. Seventy-four of the 83 patients (89%) received one or more courses of PCV; their median survival was 55 weeks. Total resection was performed in 20% (15 of 74), subtotal resection in 69% (51 of 74), and biopsy in 11% (8 of 74); reoperation (total or subtotal resection) was performed in 28 patients (37%). Survival was worst for those > or = 61 year old (median 35 weeks). Fits of the Cox proportional hazards regression model showed covariates individually predictive of improved survival were younger age (p < 0.01), smaller log of radiation volume (p = 0.008), total or subtotal resection vs. biopsy (p = 0.056), and higher Karnofsky performance status (p = 0.055). A multivariate analysis showed that age (p = 0.013) and extent of initial surgery (p = 0.003) together were predictive of a better survival with no other variables providing additional significance. Only 8.4% (7 of 83) of patients had clinically documented therapy-associated neurotoxicity ("radiation necrosis"). CONCLUSION: When comparable selection criteria were applied, the survival in this study is similar to the results currently attainable with other chemoradiation approaches. The relative safety of accelerated fractionated radiotherapy, as used in this study with carboplatin, enables concomitant full-dose administration of chemotherapy or radiosensitizing agents in glioblastoma multiforme patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Carboplatina/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/radioterapia , Adulto , Idoso , Neoplasias Encefálicas/cirurgia , Quimioterapia Adjuvante , Terapia Combinada , Progressão da Doença , Intervalo Livre de Doença , Esquema de Medicação , Glioblastoma/cirurgia , Humanos , Lomustina/administração & dosagem , Pessoa de Meia-Idade , Procarbazina/administração & dosagem , Análise de Sobrevida , Vincristina/administração & dosagem
15.
Int J Radiat Oncol Biol Phys ; 32(3): 589-97, 1995 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-7790243

RESUMO

PURPOSE: To establish the feasibility of performing split-course accelerated hyperfractionation (AHFX-S) and concomitant boost accelerated fractionation radiotherapy (AFX-C) for advanced head and neck cancer in a multi-institutional cooperative trial setting and to evaluate the tumor clearance rate and acute and late toxicity of these fractionation schedules. METHODS AND MATERIALS: Between February 1989 and January 1990, 75 patients with Stage III or IV squamous cell carcinoma of the head and neck were randomized to receive: (a) AHFX-S: 1.6 Gy/fraction, twice daily (6-h interval), 5 days/week, to a total dose of 67.2 Gy/42 fractions/6 weeks, with a 2-week rest after 38.4 Gy; or (b) AFX-C: 1.8 Gy/fraction/day, 5 daily fractions/week to 54 Gy/30 fractions/6 weeks to a large field and 1.5 Gy/fraction/day to a boost field, 6 h after large field treatment during the last 11 treatment days, to a total dose of 70.5 Gy/41 fractions/6 weeks. Acute and late toxicities were scored according to the RTOG normal tissue reaction scales and tumor clearance was evaluated at completion of therapy and at regular intervals thereafter. RESULTS: Of the 70 analyzable patients, 38 received AHFX-S and 32 received AFX-C. The two arms were balanced with respect to sex, age, T-stage, and Karnofsky Performance Status (KPS). However, the AHFX-S arm had a higher proportion of oropharyngeal primaries (63% vs. 44%), and Stage IV disease (82% vs. 50%) and lower proportion of oral cavity lesions (3% vs. 22%) and N0 disease (16% vs. 31%) than the AFX-C arm. The median follow-up was 2 years (range: 0.03-4.87 years). Tolerance of both variants of accelerated fractionated radiotherapy was satisfactory. There was no significant difference in local-regional control, disease-free survival, or survival between the two arms. The 2-year local-regional failure rate, survival, and disease-free survival was 50, 50, and 40%, respectively, for the entire group of patients. Acute radiation mucositis was increased in both arms. There was no significant difference in the incidence of grade 3 acute toxicities (63% vs. 56%) and grade 3 (14% vs. 14%) or grade 4 (6% vs. 17%) late toxicities. Permanent grade 4 late toxicity was observed in 6 and 7% of the patients, respectively. CONCLUSION: Results of this randomized Phase I/II trial showed that the two accelerated fractionated schedules studied can be successfully given in a multi-institutional cooperative trial. There was no significant difference in acute or late toxicities, local-regional control, disease-free survival, or survival in this small scale study. Therefore, a Phase III trial comparing the relative efficacy of these two accelerated fractionation schedules against standard fractionation and hyperfractionation has been activated.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Dosagem Radioterapêutica , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Intervalo Livre de Doença , Estudos de Viabilidade , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Radioterapia/efeitos adversos , Falha de Tratamento
16.
Int J Radiat Oncol Biol Phys ; 32(3): 599-604, 1995 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-7790244

RESUMO

PURPOSE: To compare the efficacy of fast-neutron radiotherapy with that of conventionally fractionated photon therapy in the management of patients with locally advanced squamous cell carcinoma of the head and neck. METHODS AND MATERIALS: Patients with Stage III or IV disease were randomized to receive either 20.4 Gy/12 fractions/4 weeks of neutrons or 70 Gy/35 fractions/7 weeks of photons (control). Between April 1986 and March 1991, 178 patients were entered, 169 of whom were eligible for analysis. The treatment arms were balanced for age, stage, and performance status, but not for primary site of origin. RESULTS: Complete response occurred in 70 and 52% with neutrons and photons, respectively (p = 0.006). Local regional failure at 3 years for all patients was 63% for neutrons and 68% for photons. Actuarial overall survival curves were virtually identical in both study arms, falling to 27% at 3 years. Acute toxicity was similar in the two arms, but late grade 3-5 toxicity was 40% with neutrons compared to 18% with photons (p = 0.008). CONCLUSION: Although the initial response rate was higher with neutrons, permanent local control and survival were not improved, and the incidence of late normal tissue toxicity was increased. As a result, fast-neutron therapy for advanced squamous cell carcinoma of the head and neck can only be recommended for patients in whom the logistic benefit of treatment in 12 sessions over 4 weeks outweighs the increased risk of late toxicity.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Nêutrons Rápidos/uso terapêutico , Neoplasias de Cabeça e Pescoço/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Análise de Sobrevida
17.
AJNR Am J Neuroradiol ; 16(4): 715-26, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7611028

RESUMO

PURPOSE: To present MR findings of parenchymal brain injury after accelerated fractionation radiation therapy combined with carboplatin chemotherapy in the treatment of malignant brain gliomas. METHODS: Eighty-one evaluable subjects in an ongoing treatment protocol for malignant gliomas form the patient base for this report. After surgical resection of tumors, patients underwent a course of accelerated fractionation radiation therapy to a total dose of 60 Gy. Carboplatin was infused intravenously before each radiation treatment. Precontrast and postcontrast MR scans were obtained before treatment and at 4-week intervals afterward and were analyzed retrospectively. RESULTS: Posttreatment MR imaging in 20 of the 81 patients showed development of unusual parenchymal lesions or enlarging masses needing debulking, and these patients underwent second operations. Two groups emerged: those with tumor and necrotic brain (n = 11) and those with necrosis and reactive gliosis but no definitive tumor (n = 9). Enhancing lesions in the tumor-negative group appeared later than those in the tumor-positive group, were often multiple, and were usually located several centimeters away from the tumor resection site or even contralaterally. Common locations were the corpus callosum and corticomedullary junctions. Lesions in the tumor-positive group were more often solitary and located immediately adjacent to the surgical site. Positive and negative results of positron emission tomography with fludeoxyglucose F 18 were obtained in both groups. The incidence of brain necrosis without associated tumor was 11%. CONCLUSIONS: A pattern of unusual enhancing parenchymal brain lesions was seen on MR imaging after accelerated fractionation radiation therapy and concomitant carboplatin chemotherapy. The abnormalities seem more extensive than focal necrotic lesions on enhanced CT or MR imaging after conventional radiation therapy, and they may mimic recurrent tumor.


Assuntos
Dano Encefálico Crônico/induzido quimicamente , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Carboplatina/efeitos adversos , Irradiação Craniana , Glioma/tratamento farmacológico , Glioma/radioterapia , Lesões por Radiação/diagnóstico , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Encéfalo/efeitos da radiação , Dano Encefálico Crônico/diagnóstico , Neoplasias Encefálicas/patologia , Carboplatina/administração & dosagem , Quimioterapia Adjuvante , Terapia Combinada , Craniotomia , Glioma/patologia , Humanos , Infusões Intravenosas , Necrose , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/radioterapia , Dosagem Radioterapêutica , Radioterapia Adjuvante , Reoperação , Técnicas Estereotáxicas
18.
Int J Oncol ; 7(4): 855-62, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21552914

RESUMO

To avoid the delayed consequences of treatment with radiotherapy, an effort was made to determine if patients with rhabdomyosarcoma could be cured with chemotherapy as the sole form of treatment. Alternatively, if radiotherapy and/or surgery were required to reduce the severity and incidence of delayed sequelae, an effort was made to determine if there was an optimum safe period for delaying implementation of these definitive forms of treatment. In patients where primary (immediate) definitive non-mutilating surgical extirpation of tumor was not feasible, exclusive treatment with chemotherapy was implemented. If considered necessary or appropriate, delayed surgery and/or radiation therapy were employed in 3 circumstances: (i) to consolidate a partial response; (ii) failure to respond; (iii) recurrent disease. The outcome of the delays prior to the implementation of definitive therapy was analyzed as a function of local and systemic recurrence and cure. Fifty-two patients were evaluated. Seven underwent primary non-mutilating surgical extirpation of localized tumor followed by adjuvant chemotherapy. The remaining 45 were treated with primary chemotherapy and 44 responded. Actuarial survival curves of the delay in initiating definitive therapy in the 52 patients revealed that the optimum delay to attain the best survival was 5 months. In circumstances where definitive therapy was not electively introduced, recurrent disease during remission appeared between 7 and 14 months in 7 patients on continued treatment, and in one patient at 30 months, 8 months after discontinuation of chemotherapy. Based upon the 5-month delay an analysis of survival was performed: Definitive therapy was introduced in 14 patients within 5 months and 7 were cured. In the remaining 31 patients, definitive therapy was introduced between 5 and 30 months and 15 were cured. The five month delay is supported empirically by tumor doubling times. No patient was cured exclusively with chemotherapy.

19.
Int J Radiat Oncol Biol Phys ; 28(1): 47-54, 1994 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-8270459

RESUMO

PURPOSE: To evaluate the effectiveness of fast neutron radiation therapy in treatment of locally advanced carcinomas of the prostate. METHODS AND MATERIALS: From April 1986 to October 1990, 178 patients were entered on a prospective, multi-institutional randomized study of the NCI-sponsored Neutron Therapy Collaborative Working Group. This trial compared external beam photon irradiation (7000-7020 cGy) with external beam neutron irradiation (2040 ncGy) for patients with high-grade T2 or T3-4, N0-1, M0 adenocarcinomas of the prostate. Eighty-nine patients were randomized to each treatment. Six patients were subsequently judged to be ineligible, leaving 85 photon and 87 neutron randomized patients eligible for analysis. RESULTS: With a follow-up time ranging from 40 to 86 months (68 months median follow-up) the 5-year actuarial clinical local-regional failure rate for patients treated with neutrons was 11%, vs. 32% for photons (p < 0.01). Incorporating the results of routine posttreatment prostate biopsies, the resulting "histological" local-regional tumor failure rates were 13% for neutrons vs. 32% for photons (p = 0.01). To date, actuarial survival and cause-specific survival rates are statistically indistinguishable for the two patient cohorts, with 32% of the neutron-treated patient deaths and 41% of the photon-treated patient deaths caused by prostate cancer (p = n.s.). Prostate specific antigen (PSA) values were elevated in 17% of neutron-treated patients and 45% of photon-treated patients at 5 years (p < 0.001). Severe late complications of treatment were higher for the neutron-treated patients (11% vs. 3%), and were inversely correlated with the degree of neutron beam shaping available at the participating institutions. Neutron treatment delivery utilizing a fully rotational gantry and multileaf collimator did not result in an increase in severe late effects when compared to photon treatment. CONCLUSION: High energy fast neutron radiotherapy is safe and effective when adequate beam delivery systems and collimation are available, and it is significantly superior to external beam photon radiotherapy in the local-regional treatment of large prostate tumors.


Assuntos
Adenocarcinoma/radioterapia , Nêutrons Rápidos , Neoplasias da Próstata/radioterapia , Radioterapia de Alta Energia , Adenocarcinoma/epidemiologia , Adenocarcinoma/patologia , Nêutrons Rápidos/efeitos adversos , Seguimentos , Humanos , Masculino , Recidiva Local de Neoplasia/epidemiologia , Fótons , Estudos Prospectivos , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/patologia , Radioterapia de Alta Energia/efeitos adversos , Taxa de Sobrevida
20.
Int J Radiat Oncol Biol Phys ; 27(3): 499-505, 1993 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-8226141

RESUMO

PURPOSE: To determine, with a prospective, multicenter randomized study, whether fast neutron radiation therapy improves the outcome for patients with non-small cell lung cancer, as compared to conventional photon radiotherapy. METHODS AND MATERIALS: From September 1986 to March 1991, a total of 200 patients with inoperable regional non-small cell lung cancer were randomized to 20.4 Gy in 12 fractions with neutrons versus 66 Gy in 33 fractions with photons. Inoperable patients with Radiation Therapy Oncology Group Stages I, II, III, or IV(M0) disease, Karnofsky Performance Score > or = 70, and who had received no previous therapy for their non-small cell lung cancer were eligible for the study. Of the 200 patients randomized, a total of 193 patients, 99 on the neutron arm and 94 on the photon arm, were eligible for analysis. The two treatment groups were balanced with regards to prognostic factors. At the time of this analysis, the median at-risk follow-up was 33 months, with a minimum follow-up of 16 months. RESULTS: No difference in overall survival was observed; however, there was a statistically significant improvement in survival for patients with squamous cell histology (p = 0.02), and a trend toward improved survival for those with favorable prognostic factors (i.e., patients who were not T4, N3, and had no pleural effusion or weight loss > 5% from baseline) (p = 0.15), favoring the neutron-treated group. With the exception of skin and subcutaneous changes, acute and late toxicity was similar in both arms. CONCLUSION: In selected patients with inoperable regional non-small cell lung cancer (e.g., squamous cell histology, favorable prognostic factors), fast neutron irradiation provides a therapeutic benefit over conventional photon radiotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma de Células Escamosas/radioterapia , Nêutrons Rápidos/uso terapêutico , Neoplasias Pulmonares/radioterapia , Fótons/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma de Células Escamosas/mortalidade , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taxa de Sobrevida
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