Head-to-Head Intra-Individual Comparison of Biodistribution and Tumor Uptake of [18F]FAPI-74 with [18F]FDG in Patients with PDAC: A Prospective Exploratory Study.

BACKGROUND: Radiolabeled fibroblast activation protein (FAP) ligands, a novel class of tracers for PET/CT imaging, have demonstrated very promising results in various oncological, as well as in some benign, diseases with long-term potential to supplant the current pan-cancer agent [18F]FDG in some cancer types. Pancreatic ductal carcinoma (PDAC) belongs to the group of epithelial malignancies with a strong so-called "desmoplastic reaction", leading to a prominent tumor stroma with cancer-associated fibroblasts that exhibit a marked overexpression of fibroblast activation protein (FAP). The first clinical experiences in PDAC with 68Ga-labeled FAP ligands suggested superior sensitivity to [18F]FDG. However, there is limited data with 18F-labeled FAP derivatives, i.e. [18F]FAPI-74, yet prospective single- and multicenter trials are already ongoing. In this proof-of-concept study, we sought to evaluate the biodistribution, tumor uptake, and lesion detectability in patients with PDAC using [18F]FAPI-74 PET/CT as compared to [18F]FDG PET/CT scans for staging. METHODS: This study includes 7 patients (median age 69) who underwent both [18F]FDG PET/CT with contrast-enhancement and [18F]FAPI-74 PET with low-dose CT for primary staging (n = 3) and therapy response control after neoadjuvant (n = 1) or re-staging after palliative therapy (n = 3). The mean interval between PET scans was 11 ± 4 days (range 1-15 days). The [18F]FDG and [18F]FAPI-74 PET/CT scans were acquired at 64 ± 4.1 min (range 61-91 min) and 66.4 ± 6.3 min (range 60-76 min), respectively, after administration of 200 ± 94 MBq (range 79-318 MBq) and 235 ± 88 MBq (range 90-321 MBq), respectively. Quantification of tracer uptake was determined with SUVmax and SUVmean. Furthermore, the tumor-to-background ratio (TBR) was derived by dividing the SUVmax of tumor lesions by the SUVmax of adipose tissue, skeletal muscle, and blood pool. RESULTS: Overall, 32 lesions were detected in 7 patients including primary (n = 7), lung (n = 7), bone (n = 3), lymph node (n = 13), and peritoneal metastases (n = 2). [18F]FAPI-74 detected 22% more lesions compared with [18F]FDG with a better TBR and visual lesion delineation. In one patient the primary lesion could be detected unequivocally with [18F]FAPI-74 but was missed by [18F]FDG imaging. Altogether, most of the lesions demonstrated markedly elevated uptake of [18F]FAPI-74 with a simultaneous lower uptake in the background, providing a very high visual contrast. CONCLUSION: To the best of our knowledge, this is the first, prospective, intra-individual investigation comparing [18F]FAPI-74 with [18F]FDG imaging in PDAC with encouraging results. These pivotalresults supporta larger, multicentric, prospective study to determine the value of [18F]FAPI-74 in detecting and staging PDAC in comparison with current standard of care imaging.

[Quality of life in patients with prostate cancer: validation of an instrument for clinical practice]. / Calidad de vida en pacientes con cáncer de próstata: la validación de un instrumento para la práctica clínica.

OBJECTIVES: Currently there are instruments to evaluate the different features of the impact on quality of life in those patients with prostate cancer undergoing any type of treatment, but most of them have 50 or more questions and they are difficult to apply in clinical practice. An English validation of a shortened version of the EPIC (Expanded Prostate Cancer Composite), the most used instrument to measure the quality of life in patients with prostate cancer, has been published recently. This version called EPIC-CP (Expanded Prostate Cancer Composite-Clinical Practice) consists of 16 questions arranged in a page, for easy and rapid clinical application. The objective of this work is to validate a Spanish version of the EPIC-CP. METHOD: An inversa-directa Spanish translation of the original version was performed. The EPIC-CP and EQ5D questionnaires were applied to 46 patients eligible to be subjected to different treatments - open prostatectomy (OP), Robotic Prostatectomy (RP), brachytherapy (Br) or conformational radiotherapy (CR) - and 82 patients already treated (9 OP, 13 RP, 7 Br, 4 CR). For reliability evaluation, the Cronbach's alpha was used to test the internal consistency for each domain of the EPIC-CP. Treated and untreated patients' scores were compared with the Wilcoxon range sum test to assess the sensitivity to change. RESULTS: Cronbach's alpha was elevated in all the EPIC-CP domains (near or greater than 0.7), indicating a high internal consistency. There was no significant difference in age and educational level between treated and untreated patients. We found significant differences between treated and untreated patients in the total EPIC CP score, in the domains of urinary incontinence, bowel function, sexual function and hormonal function. CONCLUSION: The Spanish version of the EPIC-CP is reliable and valid, so it is a useful tool to measure the quality of life in patients with prostate cancer, as well as the impact of different treatments.

Calidad de vida en pacientes con cáncer de próstata: Validación de un instrumento para la práctica clínica / Quality of life in patients with prostate cancer: validation of an instrument for clinical practice

OBJETIVO: Actualmente existen instrumentos para evaluar los distintos aspectos en el impacto sobre la calidad de vida en aquellos pacientes portadores de cáncer de próstata que son sometidos a algún tipo de tratamiento, pero la mayoría son de 50 o más preguntas y de difícil aplicación en la práctica clínica. Recientemente se ha publicado la validación en inglés de una versión acortada del instrumento más utilizado para medir la calidad de vida en pacientes con cáncer de próstata: EPIC (Expanded Prostate Cancer Composite). Esta versión denominada EPIC-CP (Expanded Prostata Cancer Composite-Clinical Practice) consiste en 16 preguntas dispuestas en una página, de fácil y rápida aplicación clínica. El objetivo primario de este trabajo fue desarrollar y validar el cuestionario EPIC-CP en español como instrumento de evaluación de calidad de vida en pacientes con cáncer de próstata (CaP). Un objetivo secundario fue la observación de las diferencias de los aspectos que impactan en la calidad de vida entre los pacientes tratados y los candidatos a tratamiento. MÉTODOS: Se realizó una traducción inversa-directa al español de la versión original de la encuesta. Se aplicaron 128 cuestionarios de calidad de vida EPIC-CP y EQ5D (cuestionario de salud del EuroQuol Group Association) a 46 (40%) pacientes candidatos a ser sometidos a diferentes tratamientos - Prostatectomía abierta (PA), Prostatectomía robótica (PR), Braquiterapia (Br) o Radioterapia Conformacional (RC)- y a 82 (64%) pacientes ya tratados (9 PA, 13 PR, 7 Br y 4 RC). Para evaluar la confiabilidad se evaluó la consistencia interna a través del Coeficiente Alfa de Cronbach para cada categoría de la EPIC-CP. Para valorar la sensibilidad al cambio se compararon las puntuaciones en pacientes tratados y no tratados con el test de Suma de Rangos de Wilcoxon. RESULTADOS: En todos los dominios de la EPIC-CP, se obtuvo un consistencia interna elevada (alfa de Cronbach 0,66-0,9). No se encontraron diferencias significativas en la edad ni en el nivel educacional entre pacientes tratados y no tratados. Se encontraron diferencias significativas en la puntuación total de la EPIC CP entre pacientes tratados y no tratados en los dominios incontinencia urinaria (p = 0,0002), función intestinal (p = 0,04), sexual (p < 0,0001) y función hormonal (p = 0,002). CONCLUSIÓN: La versión en del EPIC-CP es confiable y válida, por lo que resulta una herramienta útil para medir la calidad de vida en pacientes con CaP, así como el impacto de distintos tratamientos en ella

OBJECTIVES: Currently there are instruments to evaluate the different features of the impact on quality of life in those patients with prostate cancer undergoing any type of treatment, but most of them have 50 or more questions and they are difficult to apply in clinical practice. An English validation of a shortened version of the EPIC (Expanded Prostate Cancer Composite), the most used instrument to measure the quality of life in patients with prostate cancer, has been published recently. This version called EPIC-CP (Expanded Prostate Cancer Composite-Clinical Practice) consists of 16 questions arranged in a page, for easy and rapid clinical application. The objective of this work is to validate a Spanish version of the EPIC-CP. METHOD: An inversa-directa Spanish translation of the original version was performed. The EPIC-CP and EQ5D questionnaires were applied to 46 patients eligible to be subjected to different treatments - open prostatectomy (OP), Robotic Prostatectomy (RP), brachytherapy (Br) or conformational radiotherapy (CR) - and 82 patients already treated (9 OP, 13 RP, 7 Br, 4 CR). For reliability evaluation, the Cronbach's alpha was used to test the internal consistency for each domain of the EPIC-CP. Treated and untreated patients' scores were compared with the Wilcoxon range sum test to assess the sensitivity to change. RESULTS: Cronbach's alpha was elevated in all the EPIC-CP domains (near or greater than 0.7), indicating a high internal consistency. There was no significant difference in age and educational level between treated and untreated patients. We found significant differences between treated and untreated patients in the total EPIC CP score, in the domains of urinary incontinence, bowel function, sexual function and hormonal function. CONCLUSIÓN: The Spanish version of the EPIC-CP is reliable and valid, so it is a useful tool to measure the quality of life in patients with prostate cancer, as well as the impact of different treatments

Circulating Prostate Cells Found in Men with Benign Prostate Disease Are P504S Negative: Clinical Implications.

Introduction. Developments in immunological and quantitative real-time PCR-based analysis have enabled the detection, enumeration, and characterization of circulating tumor cells (CTCs). It is assumed that the detection of CTCs is associated with cancer, based on the finding that CTCs can be detected in all major cancer and not in healthy subjects or those with benign disease. Methods and Patients. Consecutive men, with suspicion of prostate cancer, had blood samples taken before prostate biopsy; mononuclear cells were obtained using differential gel centrifugation and CPCs detecting using anti-PSA immunocytochemistry. Positive samples underwent further classification with anti-P504S. Results. 329 men underwent prostate biopsy; of these men 83 underwent a second biopsy and 44 a third one. Of those with a biopsy negative for cancer, 19/226 (8.4%) had CPCs PSA (+) P504S (-) detected at first biopsy, 6/74 (8.1%) at second biopsy, and 5/33 (15.2%) at third biopsy. Men with cancer-positive biopsies did not have PSA (+) P504S (-) CPCs detected. These benign cells were associated with chronic prostatitis. Conclusions. Patients with chronic prostatitis may have circulating prostate cells detected in blood, which do not express the enzyme P504S and should be thought of as benign in nature.

Secondary circulating prostate cells predict biochemical failure in prostate cancer patients after radical prostatectomy and without evidence of disease.

INTRODUCTION: Although 90% of prostate cancer is considered to be localized, 20%-30% of patients will experience biochemical failure (BF), defined as serum PSA >0.2 ng/mL, after radical prostatectomy (RP). The presence of circulating prostate cells (CPCs) in men without evidence of BF may be useful to predict patients at risk for BF. We describe the frequency of CPCs detected after RP, relation with clinicopathological parameters, and association with biochemical failure. METHODS AND PATIENTS: Serial blood samples were taken during followup after RP, mononuclear cells were obtained by differential gel centrifugation, and CPCs identified using standard immunocytochemistry using anti-PSA monoclonal antibodies. Age, pathological stage (organ confined, nonorgan confined), pathological grade, margin status (positive, negative), extracapsular extension, perineural, vascular, and lymphatic infiltration (positive, negative) were compared with the presence/absence of CPCs and with and without biochemical failure. Kaplan Meier methods were used to compare the unadjusted biochemical failure free survival of patients with and without CPCs. RESULTS: 114 men participated, and secondary CPCs were detected more frequently in patients with positive margins, extracapsular extension, and vascular and lymphatic infiltration and were associated with biochemical failure independent of these clinicopathological variables, and with a shorter time to BF. CONCLUSIONS: Secondary CPCs are an independent risk factor associated with increased BF in men with a PSA <0.2 ng/mL after radical prostatectomy, but do not determine if the recurrence is due to local or systemic disease. These results warrant larger studies to confirm the findings.

Differential expression of matrix metalloproteinase-2 expression in disseminated tumor cells and micrometastasis in bone marrow of patients with nonmetastatic and metastatic prostate cancer: theoretical considerations and clinical implications-an immunocytochemical study.

Matrix metalloproteinase-2 (MMP-2) is important in the dissemination and invasion of tumor cells and activates angiogenesis. We present an immunocytochemical study of MMP-2 expression in circulating prostate cells (CPCs), disseminated tumor cells (DTCs), and micrometastasis (mM) in bone marrow of men with prostate cancer. Methods and Patients. Tumor cells were identified with anti-PSA immunocytochemistry. Positive samples underwent processing with anti-MMP-2, its expression was compared with Gleason score, concordance of expression, and metastatic and nonmetastatic disease. Results. 215 men participated, CPCs were detected in 62.7%, DTCs in 62.2%, and mM in 71.4% in nonmetastatic cancer; in metastatic cancer all had CPCs, DTCs, and mM detected. All CPCs and DTCs expressed MMP-2; in mM MMP-2 expression was positively associated with increasing Gleason score. MMP-2 expression in CPCs and DTCs showed concordance. In low grade tumors, mM and surrounding stromal cells were MMP-2 negative, with variable expression in high grade tumors; in metastatic disease, both mM and stromal cells were MMP-2 positive. Conclusions. CPCs and DTCs are different from mM, with inhibition of MMP-2 expression in mM of low grade tumors. With disease progression, MMP-2 expression increases in both mM and surrounding stromal cells, with implications for the use of bisphosphonates or MMP-2 inhibitors.

Positive HER-2 protein expression in circulating prostate cells and micro-metastasis, resistant to androgen blockage but not diethylstilbestrol.

INTRODUCTION: HER-2 expression in prostate cancer is associated with a worse prognosis and is suggested to play a role in androgen resistance. We present a study of HER-2 expression in circulating tumor cells and micrometastasis in bone marrow and the effect of androgen blockage or DES in the presence of HER-2 expressing cells. PATIENTS AND METHODS: A multicenter study of men with prostate cancer, treated with surgery, radiotherapy, or observation, and with or without hormone therapy. Mononuclear cells were separated from blood and bone marrow aspirate by differential centrifugation, touch preps were made from bone marrow biopsy samples. Prostate cells were detected using anti-PSA monoclonal antibody and standard immunocytochemistry. Positive samples were processed using Herceptest® to determine HER-2 expression. After 1 year, patients were re-evaluated and the findings of HER-2 expression and PSA change compared with treatment. RESULTS: Total 199 men participated, and 97 had a second evaluation 1 year later, frequency of HER-2 expression in circulating tumor cells and micrometastasis was 18% and 21%, respectively. There was no significant difference in HER-2 expression in the pretreatment group, after radical surgery or radiotherapy or with biochemical failure. Men with androgen blockade had a significantly higher expression of HER-2 (58%) (P =0.001). Of the 97 men with a second evaluation, 56 were in the observation arm, 27 androgen blockade, and 14 DES. Use of androgen blockade or DES significantly reduced serum PSA levels in comparison with observation (P =0.001). However, there was a significant increase in HER-2 expression in patients with androgen blockade (P =0.05) en comparison with observation or DES treatment. No patient with observation or DES became HER-2 positive, en comparison 4/22 patients initially HER-2 negative became HER-2 positive with androgen blockade. CONCLUSIONS: The results suggest that HER-2 positive cells are resistant to androgen blockade. In an environment lacking androgens, HER-2 positive cells are selected and survive, while HER-2 negative cells are eliminated thus decreasing the serum PSA. The population of HER-2 positive cells proliferate producing androgen-independent disease. DES does not increase HER-2 expression possibly by stimulating beta-estrogen receptors and blocking HER-2 androgen receptor activation.

P504S expressing circulating prostate cells as a marker for prostate cancer.

Prostate cancer is the most commonly diagnosed cancer in men and the second leading cause of cancer deaths. The serum prostate specific antigen (PSA) is the only biomarker routinely used in screening. The aim of this study was to develop a system to test the presence of circulating prostate cells in men without a diagnosis of prostate cancer in relation with age, serum PSA levels and prostate biopsy by determining the co-expression of several markers such as CD82, HER-2 and matrix metalloproteinase 2 (MMP-2). For this purpose mononuclear cells were separated from blood using differential centrifugation and then prostate cells were identified by using standard immunocytochemical method. Results indicated that among 409 men screened for prostate cancer 16.6% were positive for circulating prostate cells. Cells were positive for MMP-2 and HER-2 in 100 and 14.3% of cases, respectively, without an association with age or PSA levels. However, CD82 protein expression was associated with older age and low grade tumors. It can be concluded that the study of circulating prostate cells with various markers could be a useful complementary screening test for prostate cancer in men with increased PSA level.

Detection and characteristics of primary circulating prostate cells; association with micrometastasis and implications for surgical treatment of men with prostate cancer.

OBJECTIVES: To determine the frequency of primary circulating prostate cells in men with prostate cancer at the time of diagnosis, the association with micrometastasis, sub-classification for CD82 and the relation with pathological stage. To determine their clinical usefulness to identify patients in whom radical prostatectomy would be first choice therapy. METHODS: Men with the diagnosis of prostate cancer before definitive therapy. Blood and bone marrow samples were taken, mononuclear cells separated by differential centrifugation and prostate cells identified with immunocytochemistry using anti-PSA. Positive samples were sub-classified with anti-CD82. Details of serum PSA, Gleason score and pathological stage were registered. RESULTS: Of 77 men 58 (75.3%) had primary CPCs detected, there was an association with stage but not Gleason. 31 (40.3%) had micrometastasis with an association with stage and Gleason score. CPC-negative patients had fewer micrometastasis detected, 1/19 versus 30/58 (p<0.003). There was an inverse relation between CD82 expression and Gleason score, men with CPCs expressing CD82 had fewer micrometastasis. The combined group of CPC negative and CPC positive CD82 positive men showed a sensitivity of 87%and specificity of 73.9% for the absence of micrometastasis. CONCLUSIONS: The detection of CPCs and sub-classification with CD82 could be clinically useful to identify men with a significantly lower risk of micrometastais and as a consequence to identify men in whom radical prostatectomy could be the best initial treatment.

Deteccion y características de células prostáticas circulantes primarias, asociación con la presencia de micrometástasis y las implicaciones para el tratamiento quirúrgico en hombres con cáncer prostático. El estudio ProTECT (Prostate Tumor Early Cancer Test) / Detection and characteristics of primary circulating prostate cells; association with micrometastasis and implications for surgical treatment of men with prostate cáncer

OBJETIVO: Determinar la frecuencia de células prostáticas circulantes (CPCs) primaria en hombres con cáncer de próstata en el momento del diagnóstico, la asociación con micrometástasis ósea y subclasificación por CD82. Determinar la relación con la estadio patológica y la eficacia para seleccionar pacientes para la prostatectomía radical.MÉTODOS: Se incluyeron hombres con diagnóstico de cáncer de próstata previo a tratamiento definitivo. Se obtuvieron muestras de sangre y de médula ósea, las células mononucleares separadas por centrifugación diferencial y células prostáticas identificadas con inmumocitoquímica con anti-APE, las muestras positivas fueron sub-clasificadas con anti-CD82. Se registraron también los detalles de APE sérico, Índice de Gleason y estadio patológica.RESULTADOS: De 77 hombres, 58 (75,3%) tuvieron 1° CPCs detectadas. Hubo una asociación con estadio pero no con el Índice de Gleason, 31 (40,3%) tuvieron micrometástasis. Hubo una asociación significativa con la estadio patológica y Índice de Gleason. Pacientes CPC negativa tuvieron una menor frecuencia de micrometástasis que los hombres CPC positiva 1/19 versus 30/58 (p<0,0003).Hubo una relación inversa significativa entre la expresión de CD82 en CPCs y el índice de Gleason y menor frecuencia de micrometástasis en comparación con hombres CPC CD82 positivos (p<0,0005).En el grupo de combinación de hombres CPC negativa y CPC positiva CD82 positivo la frecuencia de micrometastasis fue significativamente menor que el grupo CPC (+) CD82 (-) 5/39 versus 26/38 respectivamente(p<0,0000007), con una sensibilidad de 87% y especificidad de 73,9% para la ausencia de micrometástasis(AU)

CONCLUSIONES: La presencia de CPCs implica un riesgo mayor de desarrollar micrometástasis, la co-expresión del CD82 es asociada con tumores de bajo grado, un riesgo disminuido del desarrollo de micrometástasis óseas. Como consecuencia, el uso de la detección de CPCs primarias y su sub-clasificación podrían ser clínicamente útiles para identificar los pacientes los cuales beneficiarán de una prostatectomía radical como tratamiento de primera línea(AU)

OBJECTIVES: To determine the frequency of primary circulating prostate cells in men with prostate cancer at the time of diagnosis, the association with micrometastasis, sub-classification for CD82 and the relation with pathological stage. To determine their clinical usefulness to identify patients in whom radical prostatectomy would be first choice therapy.METHODS: Men with the diagnosis of prostate cancer before definitive therapy. Blood and bone marrow samples were taken, mononuclear cells separated by differential centrifugation and prostate cells identified with immunocytochemistry using anti-PSA. Positive samples were sub-classified with anti-CD82. Details of serum PSA, Gleason score and pathological stage were registered.RESULTS: Of 77 men 58 (75.3%) had primary CPCs detected, there was an association with stage but not Gleason. 31 (40.3%) had micrometastasis with an association with stage and Gleason score. CPC-negative patients had fewer micrometastasis detected, 1/19 versus 30/58 (p<0.003).There was an inverse relation between CD82 expression and Gleason score, men with CPCs expressing CD82 had fewer micrometastasis. The combined group of CPC negative and CPC positive CD82 positive men showed a sensitivity of 87% and specificity of 73.9% for the absence of micrometastasis.CONCLUSIONS: The detection of CPCs and sub-classification with CD82 could be clinically useful to identify men with a significantly lower risk of micrometastais and as a consequence to identify men in whom radical prostatectomy could be the best initial treatment(AU)

Espresión de enzima metalproteinasa de matriz 2 (MPM-2) en células prostáticas en circulación sanguínea (CPCS) en pacientes con cáncer prostático: estudio utilizando inmunocitoquímica / Expression of matrix metalproteinasa enzyme 2 (MPM-2) in prostate cells in blood circulation (CPCS) in men with prostate cancer: an immunocytochemistry study

La metaloproteinasa de matriz-2 (MPM-2) es una gelatinasa implicada en el proceso de metástasis. Las células que expresan MPM-2pueden cruzar la matriz extracelular y diseminarse a los tejidos distantes. Presentamos un estudio de la detección de células prostáticas en la circulación sanguínea y la expresión de MPM-2 en varones con cáncer prostático antes y después de una prostatectomía radical. Método y pacientes: Estudio prospectivo, multicéntrico, de pacientes atendidos en el Hospital de Carabineros de Chile, INRAD y el Instituto de Bío-Oncología, entre los años 2006 y 2008. Después de un consentimiento informado por escrito, 4 ml de sangre venosa fueron obtenidos. Las células mononucleares fueron aisladas por centrifugación diferencial y la CPCs detectadas con anti-PSA e identificadas mediante inmunocitoquímica con un sistema basado en fosfatasa alcalina con neofuscina como cromógeno. Las muestras positivas tuvieron un segundo proceso con anti-MPM-2, un sistema de detección basado en peroxidasa y Vector VIP como cromogen. Detalles de la etapa, la edad y nivel de APE sérico fueron registrados. Resultados: 105 pacientes participaron, 30 pretratamiento y 75 postratamiento, con una edad promedio de 71,3 +/- 8,4 años. Existió una asociación entre la frecuencia de detección de CPCs, la etapa clínica y el índice de Gleason. Todas las CPCs expresaron MPM-2. Conclusiones: Los resultados confirman que la expresión de MPM-2 tiene un papel importante en la 1a y 2a diseminación de células cancerosas y no hay una asociación de los otros factores pronóstico. La presencia de las CPCs no implica la presencia de micrometástasis ni su origen de diseminación en el 2o caso de CPCs, pero implica un riesgo más elevado de la enfermedad micrometastásica. Su detección podría ser útil durante el seguimiento para la detección precoz de estos pacientes.

Objective: Matrix metalloproteinase-2 is a gelatinase implicated in the metastatic process. Cells expressing MMP-2 can cross the extracellular matrix and disseminate to other tissues. We present a study of MMP-2 express of circulating prostate cells in men with prostate cancer. Methods and Patients: A prospective, multicenter study of men with prostate cancer attending the Hospital de Carabineros de Chile, INRAD and the Instituto de BioOncología between 2006 and 2008. After written informed consent a 4 ml blood sample was taken, mononuclear cells were obtained using differential centrifugation and CPCs identified using immunocytochemistry. Positive samples with PSA staining cells underwent a second process with anti-MPM-2. Age, clinical stage, serum PSA were noted for each patient. Results: 105 patients entered the study, 30 pre-treatment and 75 post treatment, with an average age of 71.3 +/- 8.4 years. There was an association with CPC detection frequency with clinical stage and Gleason score. All CPCs expressed MMP-2. Conclusions: The results indicate that MMP-2 expression is important in the dissemination of primary and secondary prostate cancer cells, that there is no association between prognostic factors and MMP-2 expression in CPCs. The presence of CPCs does not imply the presence of micrometastasis nor origin of dissemination in the case of 2nd CPCs but the presence implies a higher risk of micrometastasis. The detection of these cells could be a useful tool in the follow up of patients with prostate cancer.

Las células prostáticas en la circulación sanguínea en pacientes con cáncer prostático expresan la proteína P504S: un estudio utilizando inmunocitoquímica / Circulating prostate cells in patients with prostate cancer express P504S: an immunocytochem

Determinar la presencia de células prostáticas en la circulación sanguínea (CPCs) en pacientes con cáncer prostático y la expresión de P504S. Método: Las células mononucleares fueron separadas de la sangre venosa por centrifugación diferencial, e identificadas utilizando anticuerpos monoclonales contra APE y P504S. Diez mujeres fueron usadas como controles. 66 hombres con cáncer prostático formaron el grupo de estudio. Resultados: 69,7 por ciento tuvieron células prostáticas en la sangre venosa, todas las células detectadas fueron positivas para la expresión de P504S. Conclusiones: La detección de células prostáticas P504S positivas en biopsias de la próstata esutilizando para el diagnóstico de cáncer, células benignas no se expresan el antígeno. Este es el primer estudio que demuestra la expresión de P504S en CPCs, con la inferencia que estas células son malignas.

To determine the expression of P504S en circulating prostate cells (CPCs) in men with prostate cancer. Method: Mononuclear cells were separated from venous blood using differential centrifugation andidentified using monoclonal antibodies against PSA and P504S. 10 women were used as controls and 66 men with prostate cancer formed the study group. Results: 69.7 percent of men were positive for CPCs, all the CPCs detected expressed the antigen P504S. Conclusions: The detection of P504S positive cells in prostate biopsies is used to determine whether they are malignant or not, benign cells are P504S negative. This is the first study to show that CPCsare P504S with the implication that they are malignant cells.