Does the Presence of Primary Circulating Prostate Cells Imply the Presence of Agressive Prostate Cancer with Early Biochemical Failure: a Comparison with the Walz Nomogram.

BACKGROUND: To determine the utility of primary circulating prostate cells (CPC) for predicting early biochemical failure after radical prostatectomy for prostate cancer and compare the results with the Walz nomogram. MATERIALS AND METHODS: A single centre prospective study of men with prostate cancer treated with radical prostatectomy was conducted between 2004 and 2014. Clinicalpathological details were registered, along with total serum PSA presurgery, Gleason score, extracapsular extension, positive surgical margins, infiltration of lymph nodes, seminal vesicles and pathological stage. Primary circulating prostate cells were obtained using differential gel centrifugation and detected using standard immunocytochemistry with antiPSA. Biochemical failure was defined as a PSA >0.2ng/ml, predictive values were calculated using the Walz nomagram and CPC detection. RESULTS: A total of 285 men participated, of whom 103/285 (36.1%) suffered biochemcial failure; 32/103 (31.1%) within two years of radical prostatectomy. Men with higher Gleason scores, higher pathological stage, infiltration of the surgical margin or prostate capsule and infiltration of seminal vesicles were more likely to undergo biochemical failure. There was a significant increase in the frequency of biochemical failure with increasing number of CPCs detected (p<0.0004 Chi squared for trend) and increasing percent prediction for the Walz nomogram (p<0.0001 Chi squared for trends). The positive predictive value of primary CPC detection, even using a cutoff point of ≥ 4 cells/sample was very low. CONCLUSIONS: The detection of primary CPCs in men as a prognostic factor pretreatment fails to identify those at high risk of biochemical failure within two years of curative therapy. This is in keeping with their biological significance, that the majority of them will be eliminated by the primary therapy and thus have no influence on the subsequent clinical history of the patient.

Head to Head Comparison of the Chun Nomogram, Percentage Free PSA and Primary Circulating Prostate Cells to Predict the Presence of Prostate Cancer at Repeat Biopsy.

BACKGROUND: The limitations of total serum PSA values remain problematic, especially after an initial negative prostate biopsy. In this prospective study of Chilean men with a continued suspicion of prostate cancer due to a persistently elevated total serum PSA, abnormal digital rectal examination and initial negative prostate biopsy were compared with the use of the on-line Chun nomagram, detection of primary malignant circulating prostate cells (CPCs) and free percent PSA to predict a positive second prostate biopsy. We hypothesized that men negative for circulating prostate cells have a small risk of clinically significant prostate cancer and thus may be conservatively observed. Men positive for circulating prostate cells should undergo biopsy to confirm prostate cancer. MATERIALS AND METHODS: Consecutive men with a continued suspicion of prostate cancer underwent 12 core TRUS prostate biopsy; age, total serum PSA and percentage free PSA and Chun nomagram scores were registered. Immediately before biopsy an 8ml blood simple was taken to detect primary mCPCs. Mononuclear cells were obtained by differential gel centrifugation and identified using double immunostaining with anti-PSA and anti-P504S. Biopsies were classifed as cancer/no-cancer, mCPC detecton test as negative/positive and the total number of cells/8ml registered. Areas under the curve (AUC) for percentage free PSA, Chun score and CPCs were calculated and compared. Diagnostic yields were calculated with reference to the number of possible biopsies that could be avoided and the number of clinically significant cancers that would be missed. RESULTS: A total of 164 men underwent a second biopsy; 41 (25%) had cancer; the AUCs were 0.65 for free PSA, 0.76 for the Chun score and 0.87 for CPC detection, the last having a significantly superior prediction value (p=0.01). Using cut off values of free PSA <10%, Chun score >50% and ≥1 CPC detected, CPC detection had a higher diagnostic yield. Some 4/41 cancers complied with the criteria for active surveillance, free PSA and the Chun score missed a higher number of significant cancers when compared with CPC detection. CONCLUSIONS: Primary CPC detection outperformed the use of free PSA and the Chun nomagram in predicting clinically significant prostate cancer at repeat prostate biopsy.

Limited improvement of incorporating primary circulating prostate cells with the CAPRA score to predict biochemical failure-free outcome of radical prostatectomy for prostate cancer.

OBJECTIVE: To establish a prediction model for early biochemical failure based on the Cancer of the Prostate Risk Assessment (CAPRA) score, the presence or absence of primary circulating prostate cells (CPC) and the number of primary CPC (nCPC)/8ml blood sample is detected before surgery. PATIENTS AND METHODS: A prospective single-center study of men who underwent radical prostatectomy as monotherapy for prostate cancer. Clinical-pathological findings were used to calculate the CAPRA score. Before surgery blood was taken for CPC detection, mononuclear cells were obtained using differential gel centrifugation, and CPCs identified using immunocytochemistry. A CPC was defined as a cell expressing prostate-specific antigen and P504S, and the presence or absence of CPCs and the number of cells detected/8ml blood sample was registered. Patients were followed up for up to 5 years; biochemical failure was defined as a prostate-specific antigen>0.2ng/ml. The validity of the CAPRA score was calibrated using partial validation, and the fractional polynomial Cox proportional hazard regression was used to build 3 models, which underwent a decision analysis curve to determine the predictive value of the 3 models with respect to biochemical failure. RESULTS: A total of 267 men participated, mean age 65.80 years, and after 5 years of follow-up the biochemical-free survival was 67.42%. The model using CAPRA score showed a hazards ratio (HR) of 5.76 between low and high-risk groups, that of CPC with a HR of 26.84 between positive and negative groups, and the combined model showed a HR of 4.16 for CAPRA score and 19.93 for CPC. Using the continuous variable nCPC, there was no improvement in the predictive value of the model compared with the model using a positive-negative result of CPC detection. The combined CAPRA-nCPC model showed an improvement of the predictive performance for biochemical failure using the Harrell׳s C concordance test and a net benefit on DCA in comparison with either model used separately. The use of primary CPC as a predictive factor based on their presence or absence did not predict aggressive disease or biochemical failure. CONCLUSION: Although the use of a combined CAPRA-nCPC model improves the prediction of biochemical failure in patients undergoing radical prostatectomy for prostate cancer, this is minimal. The use of the presence or absence of primary CPCs alone did not predict aggressive disease or biochemical failure.

Células prostáticas circulantes para la detección de cáncer / Circulating prostate cells for cancer detection

Introducción: El antígeno prostático específico (APE) es el marcador en suero más utilizado para la patología prostática, y el único empleado para la detección del cáncer de próstata. Si bien el APE es sumamente específico para tejido prostático, un nivel elevado no lo es para cáncer de próstata, ya que se puede ver elevado también en la enfermedad prostática benigna. Existe la necesidad de un examen simple para definir la necesidad de una biopsia prostática en hombres con un APE alterado. El examen de detección de células prostáticas malignas en sangre (CPMs) puede ser un candidato para la detección precoz del cáncer de próstata (CP). Métodos y pacientes: Analizamos de manera prospectiva un grupo de pacientes que fueron sometidos a una biopsia inicial por sospecha de cáncer de próstata y también a una segunda biopsia en el seguimiento posterior. Los resultados de la biopsia fueron comparados con las células prostáticas malignas circulantes (CPMC), las cuales fueron identificadas en muestras de sangre tomadas antes de la realización de la biopsia utilizando inmunocitoquímica estándar. El objetivo fue determinar la capacidad diagnóstica de las CPMC antes de la primera, la segunda y la tercera biopsia prostática. Resultados: En total, 423 pacientes consecutivos participaron en el estudio, con una edad promedio de 65.3 ± 8.9 años y un APE (mediana) de 5.28 ng/ml (RIQ 4.36-7.94 ng/ml). De ellos, 138 (32.6%) tuvieron un cáncer detectado en la biopsia inicial. La prueba de la detección de CPCs tuvo una sensibilidad de 0.89 (IC 95%: 0.82 a 0.94) y una especificidad de 0.89 (IC 95%: 0.84 a 0.92). De los 423 pacientes, a 125 se les reallizó una segunda biopsia, y a 57, una tercera, las CPCs lograron una sensibilidad y especificidad de 0.89/0.87 y 0.88/0.96 en la segunda y tercera biopsia, respectivamente, con un valor predictivo negativo y positivo de 0,65 / 0,97 y 0,88 / 0,95 en la segunda y tercera biopsia, en ese orden. Conclusiones: Las CPCs utilizadas en conjunto con las pruebas de tamizaje actuales, APE y tacto rectal, pueden mejorar la efectividad del tamizaje, reduciendo la frecuencia de biopsias negativas, así como su número total y sus complicaciones. Además, el costo-beneficio para el sistema de salud público en términos de utilización de recursos es positivo

Introduction: The prostate-specific antigen (PSA) is the most frequently used serum marker for the detection of prostatic disease, and the only marker used for the detection of prostate cancer. While PSA is highly specific for prostatic tissue, a high PSA serum level is not specific for prostate cancer, since it can be high even in benign prostatic disease. There is a need for a simple exam to define the opportunity of a prostate biopsy in men with an altered PSA levels. Detection of malignant prostatic cells (mCPC) in blood may be a candidate for early detection of prostate cancer (PC). Patients and methods: a group of patients, who underwent an initial prostate biopsy -and also a second one during a follow up - due to suspicion of prostate cancer, were assessed prospectively. The results of the biopsy were compared with malignant circulating prostate cells (mCPC) levels, identified in blood samples drawn prior to the biopsy, using standard immunocytochemistry methods. The objective was to determine the diagnostic ability of mCPC before the first, the second and the third prostate biopsies. Results: In total, 423 consecutive patients participated in the study, with an average age of 65.3 ± 8.9 years and a PSA (median) of 5.28 ng/ml (interquartile range [IQR] 4.36-7.94 ng/ml). Of them, 138 (32.6%) had a prostate cancer detected in the initial biopsy. Tests for the detection of circulating prostatic cells in blood (CPCs) had a sensitivity of 0.89 (95% confidence interval [95% CI: 0.82-0.94) and a specificity of 0.89 (95% CI: 0.84 to 0.92). Of the 423 patients, 125 had a second biopsy, and 57 had a third biopsy. CPCs attained a sensitivity and specificity of 0.89/0.87 and 0.88/0.96 for the second and third biopsy, respectively, with a positive and negative predictive value of 0.65 / 0.97 and 0.88 / 0.95 in the second and third biopsy, in that order. Conclusions: CPCs used in combination with current screening tests -PSA and digital rectal exam- can improve screening effectiveness by reducing the frequency of negative biopsies, as well as the total number of biopsies and their complications. In addition, profitability for the public health system in terms of resource utilization, is positive

Prediction model for early biochemical recurrence after radical prostatectomy based on the Cancer of the Prostate Risk Assessment score and the presence of secondary circulating prostate cells.

OBJECTIVE: To establish a prediction model for early biochemical recurrence based on the Cancer of the Prostate Risk Assessment (CAPRA) score and the presence of secondary circulating prostate cells (CPCs). PATIENTS AND METHODS: We conducted a prospective single-centre study of men who underwent radical prostatectomy as monotherapy for prostate cancer. Clinicopathological findings were used to calculate the CAPRA score. At 90 days after surgery, blood was taken for CPC detection, mononuclear cells were obtained using differential gel centrifugation, and CPCs were identified using immunocytochemistry. A CPC was defined as a cell expressing prostate-specific antigen (PSA) but not CD45. The CPC test results were defined as positive or negative. Patients were followed up for up to 5 years and biochemical recurrence was defined as a PSA level >0.2 ng/mL. The validity of the CAPRA score was calibrated using partial validation, and Cox proportional hazard regression to build three models: a CAPRA score model, a CPC model and a CAPRA/CPC combined model. RESULTS: A total of 321 men, with a mean age of 65.5 years, participated in the study. After 5 years of follow-up the biochemical recurrence-free survival rate was 98.55%. For the model that included CAPRA score there was a hazard ratio (HR) of 7.66, for the CPC model there was an HR of 34.52 and for the combined model there were HRs of 2.60 for CAPRA score and 22.5 for CPC. Using the combined model, 23% of men changed from the low-risk to the high-risk category, or vice versa. CONCLUSION: The incorporation of CPC detection significantly improved the model's discriminative ability in establishing the probability of biochemical recurrence; patients in the high-risk group according to CAPRA score who are negative for CPCs have a much better prognosis. The addition of CPC detection gives clinically significant information to aid the decision on who may be eligible for adjuvant therapy.

Comparison of the Walz Nomogram and Presence of Secondary Circulating Prostate Cells for Predicting Early Biochemical Failure after Radical Prostatectomy for Prostate Cancer in Chilean Men.

PURPOSE: To determine the utility of secondary circulating prostate cells for predicting early biochemical failure after radical prostatectomy for prostate cancer and compare the results with the Walz nomagram. MATERIALS AND METHODS: A single centre, prospective study of men with prostate cancer treated with radical prostatectomy between 2004 and 2014 was conducted, with registration of clinical-pathological details, total serum PSA pre-surgery, Gleason score, extracapsular extension, positive surgical margins, infiltration of lymph nodes, seminal vesicles and pathological stage. Secondary circulating prostate cells were obtained using differential gel centrifugation and assessed using standard immunocytochemistry with anti-PSA. Biochemical failure was defined as a PSA >0.2ng/ml, predictive values werecalculated using the Walz nomagram and CPC detection. RESULTS: A total of 326 men participated, with a median follow up of 5 years; 64 had biochemical failure within two years. Extracapsular extension, positive surgical margins, pathological stage, Gleason score ≥ 8, infiltration of seminal vesicles and lymph nodes were all associated with higher risk of biochemical failure. The discriminative value for the nomogram and circulating prostate cells was high (AUC >0.80), predictive values were higher for circulating prostate cell detection, with a negative predictive value of 99%, sensitivity of 96% and specificity of 75%. CONCLUSIONS: The nomagram had good predictive power to identify men with a high risk of biochemical failure within two years. The presence of circulating prostate cells had the same predictive power, with a higher sensitivity and negative predictive value. The presence of secondary circulating prostate cells identifies a group of men with a high risk of early biochemical failure. Those negative for secondary CPCs have a very low risk of early biochemical failure.

Possible Role of HER-2 in the Progression of Prostate Cancer from Primary Tumor to Androgen Independence.

BACKGROUND: The expression of HER-2 in prostate cancer has been linked to disease progression. We analysed the presence of HER-2 expression in primary tumors in men undergoing radical prostatectomy, its association with clinical and pathological findings, and its expression in secondary circulating prostate cells (CPCs) during follow up, as well as links with biochemical failure and the effects of androgen blockade. MATERIALS AND METHODS: Consecutive men undergoing radical prostatectomy for histologically confirmed prostate cancer were analyzed. HER-2 expression in the primary tumor was assessed using the HercepTest®, CPCs were identified from blood samples using standard immunocytochemistry with anti-PSA and positive samples with the HercepTest® to determine HER-2 expression. The influence of HER-2 expression on the frequency of biochemical failure and effects of androgen blockade was determined. RESULTS: 144 men with a mean age of 64.8±10.3 years participated, with a median follow up of 8.2 years. HER-2 was expressed in 20.8% of primary tumors; it was associated with vascular infiltration and older age, but not with other clinical pathological findings. Some 40.3% of men had secondary CPCs detected, of which 38% expressed HER-2. Men CPC (+) had a higher frequency of biochemical failure, but there was no difference in HER-2 expression of CPCs with the frequency of biochemical failure. After androgen blockade, men with HER-2 (+) positive secondary CPCs had a higher frequency of disease progression to castrate resistant disease. CONCLUSIONS: HER-2 plays a dual role in the progression of prostate cancer; firstly it may increase the potential of tumor cells to disseminate from the primary tumor via the blood by increasing vascular infiltration. In the presence of androgens, there is no survival advantage of expressing HER-2, but once biochemical failure has occurred and androgen blockade started, HER-2 positive cells are resistant to treatment, survive and grow leading to castration resistant disease.

Comparison of the Formula of PSA, Age, Prostate Volume and Race Versus PSA Density and the Detection of Primary Malignant Circulating Prostate Cells in Predicting a Positive Initial Prostate Biopsy in Chilean Men with Suspicion of Prostate Cancer.

BACKGROUND: Combining risk factors for prostate cancer into a predictive tool may improve the detection of prostate cancer while decreasing the number of benign biopsies. We compare one such tool, age multiplied by prostate volume divided by total serum PSA (PSA-AV) with PSA density and detection of primary malignant circulating prostate cells (CPCs) in a Chilean prostate cancer screening program. The objectives were not only to determine the predictive values of each, but to determine the number of clinically significant cancers that would have been detected or missed. MATERIALS AND METHODS: A prospective study was conducted of all men undergoing 12 core ultrasound guided prostate biopsy for suspicion of cancer attending the Hospital DIPRECA and Hospital de Carabineros de Chile. Total serum PSA was registered, prostate volumecalculated at the moment of biopsy, and an 8 ml blood simple taken immediately before the biopsy procedure. Mononuclear cells were obtained from the blood simple using differential gel centrifugation and CPCs identified using immunocytchemistry with anti- PSA and anti-P504S. Biopsy results were classed as positive or negative for cancer and if positive the Gleason score, number of positive cores and percent infiltration recorded. RESULTS: A total of 664 men participated, of whom 234 (35.2%) had cancer detected. They were older, had higher mean PSA, PSA density and lower PSA-AV. Detection of CPCs had high predictive score, sensitivity, sensibility and positive and negative predictive values, PSA-AV was not significantly different from PSA density in this population. The use of CPC detection avoided more biopsies and missed fewer significant cancers. CONCLUSIONS: In this screening population the use of CPC detection predicted the presence of clinically significant prostate cancer better than the other parameters. The high negative predictive value would allow men CPC negative to avoid biopsy but remain in follow up. The formula PSA-AV did not add to the predictive performance using PSA density.

[Expression of P504S and matrix metalloproteinase-2 in circulating prostate cells disseminated as a result of transrectal ultrasound guided biopsy as determined by immunocytochemistry: Clinical implications]. / Condideraciones clínicas de la expressión de P504S y metaloproteinasa de matriz 2 en células prostáticas circulantes en sangre diseminadas como resultado de una biopsia prostática trans-rectal guiada por ecografía.

OBJECTIVES: Surgical manipulation of cancer has been shown to increase blood borne cancer cell dissemination and increase the risk of metastasis. We present the effect of prostate biopsy on prostate cell dissemination and the phenotypic characteristics of these cells. METHODS: 50 men undergoing initial prostate biopsy for suspicion of prostate cancer were studied. Blood samples were taken immediately before, and 1 and 24 hours after biopsy for circulating prostate cells (CPC) determination and phenotypic characterization. CPCs were detected and counted using standard immunocytochemistry using anti-PSA and then characterized using anti-P504S and anti-matrix metalloproteinase-2 (MMP-2). RESULTS: 14 (28%) men had cancer detected on biopsy. 13/14 had P504S (+) and MMP-2 (+) cells detected prior to biopsy. One hour after biopsy there was a mixture of P504S (+) and P504S (-) cells detected, as well as MMP-2 (+) and MMP-2 (-) cells detected. 24 hours after biopsy the same 13/14 men remained positive, although the number of CPCs increased 1 hour after biopsy and then the numbers decreased to pre-biopsy levels after 24 hours. In cancer negative men, P504S (-) and MMP-2 (-) cells were detected, some of these cells persisted 24 hours after biopsy. CONCLUSIONS: Prostate biopsy causes dissemination of prostate cells into the circulation, both malignant and benign; the majority of them are cleared within 24 hours. There was no conversion of negative to positive result in men with cancer, this suggests that the inherent capacity of malignant CPCs to disseminate is more important than the effect of dissemination caused by prostate biopsy.

Head-to-head comparison of the Montreal nomogram with the detection of primary malignant circulating prostate cells to predict prostate cancer at initial biopsy in Chilean men with suspicion of prostate cancer.

INTRODUCTION: The limitations of total serum prostate-specific antigen (PSA) level values remain problematic. Nomograms may improve the predictive value of a positive prostate biopsy (PB) finding. We compare in a prospective study of Chilean men suspicious of having prostate cancer (PC), owing to an elevated total serum PSA or abnormal digital rectal examination finding or both, the use of the online Montreal nomogram for the detection of primary malignant circulating prostate cells (mCPCs) to predict a positive PB finding. METHODS AND PATIENTS: Consecutive men suspicious of PC underwent 12-core transrectal ultrasound PB; their age, total serum PSA levels and percent free PSA values, and Montreal nomogram scores were registered. Immediately before the PB, an 8-ml blood sample was taken to detect primary mCPCs. Mononuclear cells were obtained by differential gel centrifugation and identified using double immunomarcations with anti-PSA and anti-P504S. Biopsies were classified according to presence of cancer/no cancer. The test results for the detection of mCPC were stated as negative/positive, and the total number of cells/8 ml of blood was registered. Areas under the curve for total serum PSA level, percent free PSA value, Montreal score, and detection of mCPCs were calculated and compared. Diagnostic yields, the number of possible biopsies that could be avoided, and the number of clinically significant cancers that would be missed were calculated. RESULTS: Overall, 607 men underwent biopsy, where 197 (32.5%) had cancer. These men were significantly older, had higher total serum PSA level and Montreal score, and lower percent free PSA value. The values for area under the curve were 0.56 for total PSA level, 0.78 for percent free PSA, 0.78 for Montreal score, and 0.84 for mCPC detection; mCPC detection had a significantly superior prediction value (P = 0.018). Using cutoff values of percent free PSA < 10%, Montreal score > 50%, and ≥ 1 mCPC detected, mCPC detection had a higher diagnostic yield. Of the 197 cancers, 41 complied with the criteria for active surveillance; percent free PSA and the Montreal score missed a higher number of significant cancers when compared with mCPC detection. CONCLUSIONS: Primary mCPC detection outperformed the use of percent free PSA and the Montreal nomogram in predicting clinically significant PC at initial PB.

Prostate cancer screening in the fit Chilean elderly: a head to head comparison of total serum PSA versus age adjusted PSA versus primary circulating prostate cells to detect prostate cancer at initial biopsy.

BACKGROUND: Prostate cancer is predominately a disease of older men, with a median age of diagnosis of 68 years and 71% of cancer deaths occurring in those over 75 years of age. While prostate cancer screening is not recommended for men>70 years, fit elderly men with controlled comorbidities may have a relatively long life expectancy. We compare the use of age related PSA with the detection of primary malignant circulating prostate cells mCPCs to detect clinically significant PC in this population. MATERIALS AND METHODS: All men undergoing PC screening with a PSA>4.0 ng/ml underwent TRUS 12 core prostate biopsy (PB). Age, PSA, PB results defined as cancer/no-cancer, Gleason, number of positive cores and percentage infiltration were registered. Men had an 8 ml blood sample taken for mCPC detection; mononuclear cells were obtained using differential gel centrifugation and mCPCs were identified using immunocytochemistry with anti-PSA and anti-P504S. A mCPC was defined as a cell expressing PSA and P504S; a positive test as at least one mCPC detected/sample. Diagnostic yields for subgroups were calculated and the number of avoided PBs registered. Esptein criteria were used to define small grade tumours. RESULTS: A total of 610 men underwent PB, 398 of whom were aged <70 yrs. Men over 70 yrs had: a higher median PSA, 6.24 ng/ml versus 5.59 ng/ml (p=0.04); and a higher frequency of cancer detected 90/212 (43%) versus 134/398 (34%) (p=0.032). Some 34/134 cancers in men<70 yrs versus 22/90 (24%) of men>70 yrs complied with criteria for active surveillance. CPC detection: 154/398 (39%) men<70 yrs were CPC (+), specificity for cancer 86%, sensitivity 88%, 14/16 with a false (-) result had a small low grade PC. In men>70 years, 88/212 (42%) were CPC (+); specificity 92%, sensitivity 87%, 10/12 with a false (-) had small low grade tumours. False (+) results were more common in younger men 36/154 versus 10/88 (p<0.02). With a PSA cutoff of 6.5 ng/ml, in men<70 yrs, 108 PB would be avoided, missing 56 cancers of which 48 were clinically significant. Using CPC detection, 124 biopsies would be avoided, missing only 2 clinically significant cancers. In men>70 yrs using a PSA>6.5 ng/ml would have resulted in 108 PB with 34 PC detected, of which 14(41%) were small low grade tumours. CONCLUSIONS: The use of CPC detection in the fit elderly significantly decreases the number of PBs without missing clinically significant cancers, indicating superiority to the use of age-related PSA.

Comparison between Use of PSA Kinetics and Bone Marrow Micrometastasis to Define Local or Systemic Relapse in Men with Biochemical Failure after Radical Prostatectomy for Prostate Cancer.

BACKGROUND: Treatment of biochemical failure after radical prostatectomy for prostate cancer is largely empirically based. The use of PSA kinetics has been used as a guide to determine local or systemic treatment of biochemical failure. We here compared PSA kinetics with detection of bone marrow micrometastasis as methods to determine local or systemic relapse. MATERIALS AND METHODS: A transversal study was conducted of men with biochemical failure, defined as a serum PSA >0.2ng/ml after radical prostatectomy. Consecutive patients having undergone radical prostatectomy and with biochemical failure were enrolled and clinical and pathological details were recorded. Bone marrow biopsies were obtained from the iliac crest and touch prints made, micrometastasis (mM) being detected using anti-PSA. The clinical parameters of total serum PSA, PSA velocity, PSA doubling time and time to biochemical failure, age, Gleason score and pathological stage were registered. RESULTS: A total of 147 men, mean age 71.6 ± 8.2 years, with a median time to biochemical failure of 5.5 years (IQR 1.0-6.3 years) participated in the study. Bone marrow samples were positive for micrometastasis in 98/147 (67%) of patients at the time of biochemical failure. The results of bone marrow micrometastasis detected by immunocytochemistry were not concordant with local relapse as defined by PSA velocity, time to biochemical failure or Gleason score. In men with a PSA doubling time of < six months or a total serum PSA of >2,5ng/ml at the time of biochemical failure the detection of bone marrow micrometastasis was significantly higher. CONCLUSIONS: The detection of bone marrow micrometastasis could be useful in defining systemic relapse, this minimally invasive procedure warranting further studies with a larger group of patients.

Extended use of P504S positive primary circulating prostate cell detection to determine the need for initial prostate biopsy in a prostate cancer screening program in Chile.

BACKGROUND: To determine the frequency of primary circulating prostate cells (CPC) detection according to age and serum PSA levels in a cohort of men undergoing screening for prostate cancer and to determine the diagnostic yield in those men complying with the criteria for prostate biopsy. MATERIALS AND METHODS: A prospective study was carried out to analyze all men evaluated in a hospital prostate cancer screening program. Primary CPCs were obtained by differential gel centrifugation and detected using standard immunocytochemistry using anti-PSA, positive samples undergoing a second process with anti-P504S. A malignant primary CPC was defined as PSA+ P504S+, and a test positive if 1 cell/4ml was detected. The frequency of primary CPC detection was compared with age and serum PSA levels. Men with a PSA >4.0ng/ml and/or abnormal rectal examination underwent 12 core prostate biopsy, and the results were registered as cancer/no-cancer and compared with the presence/absence of primary CPCs to calculate the diagnostic yield. RESULTS: A total of 1,117 men participated; there was an association of primary CPC detection with increasing age and increasing serum PSA. Some 559 men underwent initial prostate biopsy of whom 207/559 (37.0%) were positive for primary CPCs and 183/559 (32.0%) had prostate cancer detected. The diagnostic yield of primary CPCs had a sensitivity of 88.5%, a specificity of 88.0%, and positive and negative predictive values of 78.3% and 94.9%, respectively. CONCLUSIONS: The use of primary CPCs for testing is recommended, since its high negative predictive value could be used to avoid prostate biopsy in men with an elevated PSA and/or abnormal DRE. Men positive for primary CPCs should undergo prostate biopsy. It is a test that could be implemented in the routine immunocytochemical laboratory.

Elimination of primary circulating prostate cells after radical prostatectomy for prostate cancer decreases the risk of future biochemical failure.

OBJECTIVES: Primary CPCs are those detected in the blood of prostate cancer patients before radical treatment; secondary CPCs are those detected afterwards. Although primary CPCs are frequently found, it has been suggested that only a few will survive and go on to form metastasis. We evaluate the frequency of primary and secondary CPC detection and the association with biochemical failure, relation with clinical-pathological parameters and clinical implications in men treated by radical prostatectomy (RP) for prostate cancer. METHODS: Serial blood samples were taken before surgery and during follow up after RP. Mononuclear cells were obtained by differential gel centrifugation, and CPCs were identified using standard immunocytochemistry using anti-PSA monoclonal antibodies. Age, pathological stage (organ confined, non organ confined), pathological grade, margin status (positive, negative), extracapsular extension, perineural, vascular, and lymphatic infiltration (positive, negative) were compared with the presence/absence of CPCs in patients with and without biochemical failure. Kaplan Meier method was used to compare the unadjusted biochemical failure free survival of patients with and without CPCs. RESULTS: 138 of 423 (32.6%) men undergoing prostate biopsy for an elevated serum PSA were diagnosed of prostate cancer. Of these men 15 (10.9%) were CPC negative. 95 CPC positive men underwent RP. There was no relation between primary CPC detection and clinical-pathological parameters; however, secondary CPCs were associated both with clinical-pathological parameters and biochemical failure. CONCLUSIONS: Primary CPCs are frequently detected in men with prostate cancer, but they are not associated with biochemical failure, so that they may be useful for prostate cancer detection but not for prognosis. The persistence of CPCs after surgery is associated with increased biochemical failure.

La eliminación de células prostáticas circulantes primarias en sangre posterior a la prostatectomía radical disminuye el riesgo de recidiva bioquímica / Elimination of primary circulating prostate cells after radical prostatectomy for prostate cancer decreases the risk of future biochemical failure

OBJETIVO: Las células prostáticas circulantes en sangre (CPCs) primarias son aquellas células prostáticas detectadas en pacientes con cáncer de próstata antes del tratamiento quirúrgico radical, por el contrario, las CPCs secundarias son aquellas detectadas posterior a este tratamiento. Pese a que las CPCs primarias son encontradas frecuentemente en pacientes con cáncer de próstata, solo unas pocas sobreviven y formarán metástasis. Evaluamos la asociación de las CPCs primarias y secundarias con la recidiva bioquímica en hombres con cáncer de próstata tratados con prostatectomía radical. MÉTODOS: Se tomaron muestras de sangre seriadas antes y después del tratamiento quirúrgico, se obtuvieron células mononucleares por centrifugación diferencial y se identificaron las CPCs utilizando inmunocitoquímica. Los datos de edad, estadio patológico, grado patológico, márgenes quirúrgicos, extensión extracapsular, perineural, vascular e infiltración linfática fueron comparados con la presencia o ausencia de CPCs en pacientes con o sin recidiva bioquímica. Se utilizo el método de Kaplan Meyer para comparar la sobrevida libre de enfermedad de los pacientes con o sin CPCs. RESULTADOS: 138 de 423 (32,6%) de los hombres que fueron sometidos a una biopsia prostática por un PSA elevado tuvieron cáncer de próstata, de estos hombres, 15 (10,9%) fueron negativos para CPCs. De los hombres positivos, 95 fueron sometidos a una prostatectomía radical, no existió relación entre la detección de CPCs primarias y los parámetros clínico - patológicos del cáncer, sin embargo, los pacientes con CPCs secundarias se asociaron con mayor tasa de recidiva bioquímica. CONCLUSIONES: Las CPCs primarias son frecuentemente detectadas en hombres con cáncer de próstata, pero no se asocian con recidiva bioquímica, por lo tanto pueden ser útiles para la detección de cáncer de próstata pero no para su pronóstico. La detección de CPCs posterior a la cirugía se asocia con mayores posibilidades de recidiva bioquímica

OBJECTIVES: Primary CPCs are those detected in the blood of prostate cancer patients before radical treatment; secondary CPCs are those detected afterwards. Although primary CPCs are frequently found, it has been suggested that only a few will survive and go on to form metastasis. We evaluate the frequency of primary and secondary CPC detection and the association with biochemical failure, relation with clinical-pathological parameters and clinical implications in men treated by radical prostatectomy (RP) for prostate cancer. METHODS: Serial blood samples were taken before surgery and during follow up after RP. Mononuclear cells were obtained by differential gel centrifugation, and CPCs were identified using standard immunocytochemistry using anti-PSA monoclonal antibodies. Age, pathological stage (organ confined, non organ confined), pathological grade, margin status (positive, negative), extracapsular extension, perineural, vascular, and lymphatic infiltration (positive, negative) were compared with the presence/absence of CPCs in patients with and without biochemical failure. Kaplan Meier method was used to compare the unadjusted biochemical failure free survival of patients with and without CPCs. RESULTS: 138 of 423 (32.6%) men undergoing prostate biopsy for an elevated serum PSA were diagnosed of prostate cancer. Of these men 15 (10.9%) were CPC negative. 95 CPC positive men underwent RP. There was no relation between primary CPC detection and clinical-pathological parameters; however, secondary CPCs were associated both with clinical-pathological parameters and biochemical failure. CONCLUSIONS: Primary CPCs are frequently detected in men with prostate cancer, but they are not associated with biochemical failure, so that they may be useful for prostate cancer detection but not for prognosis. The persistence of CPCs after surgery is associated with increased biochemical failure

Primary circulating prostate cells are not detected in men with low grade small volume prostate cancer.

Objective. To determine if primary circulating prostate cells (CPCs) are found in all men with prostate cancer. Methods and Patients. A prospective study, to analyze all men with an elevated PSA between 4.0 and 10.0 ng/mL undergoing initial biopsy. Primary CPCs were obtained by differential gel centrifugation and detected using standard immunocytochemistry using anti-PSA; positive samples underwent a second process with anti-P504S. A malignant primary CPC was defined as PSA (+) P504S (+) and a test positive if 1 cell/4 mL was detected. Biopsy results were registered as cancer/no-cancer, number of cores positive, and percent infiltration of the cores. Results. 328/1123 (29.2%) of the study population had prostate cancer diagnosed on initial biopsy, and 42/328 (12.8%) were negative for primary CPCs. CPC negative men were significantly older, and had lower PSA levels, lower Gleason scores, and fewer positive cores and with infiltration by the cancer. 38/42 (91%) of CPC negative men complied with the criteria for active surveillance in comparison with 34/286 (12%) of CPC positive men. Conclusions. Using primary CPC detection as a sequential test to select men with an elevated PSA for biopsy, the risk of missing clinically significant prostate cancer is minimal when the patient is primary CPC negative; less than 0.5% of all primary CPC negative men had a clinically significant prostate cancer.

A comparative performance analysis of total PSA, percentage free PSA, PSA velocity, and PSA density versus the detection of primary circulating prostate cells in predicting initial prostate biopsy findings in Chilean men.

INTRODUCTION: PSA parameters have been used in an attempt to improve the diagnostic yield of prostate screening tests; the detection of primary malignant circulating prostate cells (CPCs) may improve the diagnostic yield of screening and therefore avoid unnecessary biopsies. PATIENTS AND METHODS: Prospective study of all men undergoing initial prostate biopsy due to an elevated total serum PSA. Free percent PSA, PSA velocity, and PSA density were determined. Primary CPCs were detected using standard immunocytochemistry. A positive test for CPCs was defined as one cell PSA (+) P504S (+) in an 8 ml blood sample. Positive predictive and negative predictive values, specificity, and sensitivity were calculated for each test as well as the number of biopsies avoided and cancers missed. RESULTS: 303 men participated in the study of whom 113/303 (37.3%) men had prostate cancer. Of the three PSA based parameters, free percent PSA was superior, sensitivity 70.8%, and specificity 67.4%. Primary CPCs detection had a sensitivity of 88.5% and a specificity of 88.4% avoiding 181 (59.7%) biopsies, detecting 93/95 (98%) of clinically significant cancers, and missing 13 (11.5%) low grade, small volume tumors. CONCLUSIONS: The use of primary CPCs as a sequential test could decrease the number of initial prostate biopsies missing those cancers which are treated by active observation.

Cost-Benefit of incorporating the detection of circulating prostate cells in a screening programme for prostate cancer.

OBJECTIVES: Prostate cancer is the second most common cancer in men after skin cancer, screening is used to detect early stage cancer using serum prostate specific antigen(PSA). A level of PSA 〉 4.0ng/m as a cut-off point or abnormal digital rectal examination (DRE) are used to indicate a prostate biopsy. Nevertheless, non-malignant pathologies can increase serum PSA level so that 70% of biopsies are negative for cancer, and thus potentially unnecessary, causing anxiety, costly clinical tests and prolonged follow-up. Thus the search for new biomarkers is important. Circulating primary prostate cells (CPCs) may be such a marker. We analyze a cohort of patients using CPCs to detect prostate cancer in men with a serum PSA 〉4.0ng/ml or abnormal DRE in terms of cost-benefit. METHODS: A cohort of 263 patients with a PSA 〉4.0 ng/ml and a test to detect CPCs who underwent prostate biopsy were analyzed. The results of both tests were compared with biopsy results; sensibility, specificity, and predictive values were calculated. Costs of each test, process, drug costs and complications were determined as well as indirect costs. RESULTS: Of the 263 patients, 77 (28.6%) had prostate cancer detected, for the test using CPCs there was a sensibility of 85.7%, specificity of 90.3% and negative predictive value of 93.9%. Thus men CPC negative may not need a prostate biopsy. Potential savings for the 263 patients were between €32,068 in a public health service and €69,253 for inpatient private health insurance patients. Follow up cost were higher in false-positive CPC patients but, as there were fewer false positive patients, total costs were lower. CONCLUSIONS: The use of primary CPC detection as a complementary test in men with a serum PSA 〉4.0ng/ml to indicate prostate biopsy is a specific, cost effective test, eliminating approximately 70% of prostate biopsies. This results in a significant health care saving both in direct and indirect costs, in the costs of complications. Implementation costs were minimal as equipment and reagents are part of the routine clinical laboratory. The method deserves further investigation to confirm the results.

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.