Alan W. Partin

Serum PSA, together with digital rectal examination and imaging of the prostate gland, have remained the gold standard in urological practices for the management of and intervention for prostate cancer. Based on these adopted practices, the limitations of serum PSA in identifying aggressive prostate cancer has led us to evaluate whether urinary PSA levels might have any clinical utility in prostate cancer diagnosis. Utilizing the Access Hybritech PSA assay, we evaluated a total of n = 437 urine specimens from post-DRE prostate cancer patients. In our initial cohort, PSA tests from a total of one hundred and forty-six (n = 146) urine specimens were obtained from patients with aggressive (Gleason Score ≥ 8, n = 76) and non-aggressive (Gleason Score = 6, n = 70) prostate cancer. A second cohort, with a larger set of n = 291 urine samples from patients with aggressive (GS ≥ 7, n = 168) and non-aggressive (GS = 6, n = 123) prostate cancer, was also utilized in our study. Our data demonstrated that patients with aggressive disease had lower levels of urinary PSA compared to the non-aggressive patients, while the serum PSA levels were higher in patients with aggressive prostate disease. The discordance between serum and urine PSA levels was further validated by immuno-histochemistry (IHC) assay in biopsied tumors and in metastatic lesions (n = 62). Our data demonstrated that aggressive prostate cancer was negatively correlated with the PSA in prostate cancer tissues, and, unlike serum PSA, urinary PSA might serve a better surrogate for capitulating tissue milieus to detect aggressive prostate cancer. We further explored the utility of urine PSA as a cancer biomarker, either alone and in combination with serum PSA, and their ratio (serum to urine PSA) to predict disease status. Comparing the AUCs for the urine and serum PSA alone, we found that urinary PSA had a higher predictive power (AUC= 0.732) in detecting aggressive disease. Furthermore, combining the ratios between serum to urine PSA with urine and serum assay enhanced the performance (AUC = 0.811) in predicting aggressive prostate disease. These studies support the role of urinary PSA in combination with serum for detecting aggressive prostate cancer.

Multimodal therapies were combined to eradicate the primary site, metastatic, and micrometastatic disease in men with newly diagnosed, synchronous, oligometastatic prostate cancer. The investigation included companion, phase II studies: total eradication therapy-1 (TET-1) for those treatment-naïve and total eradication therapy-2 (TET-2) for those post-prostatectomy. The treatment-naive protocol included androgen deprivation and docetaxel (with concurrent abiraterone added in a protocol amendment), followed by a prostatectomy, adjuvant radiation (if positive margins, T3/4, or detectable PSA), and metastasis-directed therapy. The post-prostatectomy protocol assigned the same therapies (omitting the prostatectomy). The primary endpoint was an undetectable PSA with recovered testosterone. The safety boundaries were ≤ 50% for grade 3/4 neutropenic and ≤ 20% for grade 3/4 surgical- and radiation-related toxicities. Enrollment was planned for 60 patients per protocol, to detect a PSA progression-free survival ≥ 32%, as compared to 15% in a historic control. Enrollment closed early. An interim analysis was conducted once > 50% of patients were evaluable for the primary endpoint. The primary endpoint duration was assessed by median progression-free survival. 52 patients were enrolled (n = 26 per protocol). Medium follow-up was 30.3 months. 80% (24/30) of evaluable patients achieved the primary endpoint; the duration was not reached. Of those not evaluable, 77% (17/22) had not reached the endpoint and 23% (5/22) had exited. There were 8% (4/52) grade 3/4 neutropenic and 2% (1/48) grade 3/4 surgical or radiation-induced toxicities. Interim findings suggest the trials’ endpoints were met, advancing the concept of total eradication therapy in men with oligometastatic prostate cancer.

51 Background: Prostate cancer (PCa) diagnostics remains challenging due to fear of over-diagnosis and overtreatment. Due to low accuracy of PSA too many men are biopsied that do not have a subsequent PCa diagnosis or that have indolent disease. Furthermore, persistent risk factors and fear of missed PCa leads to many unnecessary repeat biopsies. Most prostate tumors have epigenetic DNA-methylation aberrations, which display a field effect that can be observed in normal-appearing surrounding tissue, and that could help alleviate biopsy-sampling errors. Methods: A training cohort of methylation-positive men with a negative index biopsy followed by either a Gleason score (GS) ≥ 7 (n=43) or cancer-negative (n=226) repeat biopsy was evaluated. Using the initial negative biopsy, men were stratified for the likelihood of harboring high-grade PCa focusing on a methylation intensity algorithm involving GSTP1, RASSF1 and APC. This algorithm was validated in a cohort of 102 men, with either a PCa-free (n=20), GS6 (n=46), or GS≥7 (n=36) biopsies. Results: The methylation intensity-based algorithm was developed on PCa-negative index biopsies and optimized to predict the presence of GS≥7 cancer in a repeat biopsy. The methylation intensity was significantly higher in GS≥7 compared to PCa-free repeat biopsies (p

Approximately 1 million prostate biopsies are performed yearly in the United States, with only ~25% resulting in prostate cancer diagnosis. However, ~40% of men receive multiple biopsies for fear of cancer being missed. DNA hypermethylation is ideally suited for early disease detection and could be used to prevent unnecessary biopsies. Men with low-risk epigenetic signatures may forego subsequent biopsy and potential complications. A meta-analysis of two validation studies was conducted to gain additional insight into the benefits for patient risk stratification. In the Methylation Analysis to Locate Occult Cancer (MATLOC) study a negative predictive value of 90% was obtained, which represents a significant improvement over standard of care. This was confirmed in the Detection of Cancer Using Methylated Events in Negative Tissue (DOCUMENT) study (88% negative predictive value), which was designed to validate the performance in an independent cohort. The epigenetic assay, in combination with other known risk factors, may help reduce unnecessary repeat prostate biopsies and identify men at highest risk of harboring occult high-grade prostate cancer.

The DOCUMENT multicenter trial in the United States validated the performance of an epigenetic test as an independent predictor of prostate cancer risk to guide decision making for repeat biopsy. Confirming an increased negative predictive value could help avoid unnecessary repeat biopsies. We evaluated the archived, cancer negative prostate biopsy core tissue samples of 350 subjects from a total of 5 urological centers in the United States. All subjects underwent repeat biopsy within 24 months with a negative (controls) or positive (cases) histopathological result. Centralized blinded pathology evaluation of the 2 biopsy series was performed in all available subjects from each site. Biopsies were epigenetically profiled for GSTP1, APC and RASSF1 relative to the ACTB reference gene using quantitative methylation specific polymerase chain reaction. Predetermined analytical marker cutoffs were used to determine assay performance. Multivariate logistic regression was used to evaluate all risk factors. The epigenetic assay resulted in a negative predictive value of 88% (95% CI 85-91). In multivariate models correcting for age, prostate specific antigen, digital rectal examination, first biopsy histopathological characteristics and race the test proved to be the most significant independent predictor of patient outcome (OR 2.69, 95% CI 1.60-4.51). The DOCUMENT study validated that the epigenetic assay was a significant, independent predictor of prostate cancer detection in a repeat biopsy collected an average of 13 months after an initial negative result. Due to its 88% negative predictive value adding this epigenetic assay to other known risk factors may help decrease unnecessary repeat prostate biopsies.

Study Type – Diagnostic (exploratory cohort) Level of Evidence 2b What’s known on the subject? and What does the study add? The Epstein criteria, which utilize prostate specific antigen density (PSAD) benchmarks, are recognized to be a reasonable method of selecting men for active surveillance of prostate cancer. Transrectal ultrasonography, however, may not be a sufficiently precise method of measuring prostate volume for the determination of PSAD. This study shows that despite impressive intra‐observer variability in transrectal ultrasonography guided prostate volume measurements, this variability typically does not affect the PSAD to an extent by which qualification for active surveillance would be altered. OBJECTIVE: • To determine intra‐observer variability in transrectal ultrasonography (TRUS) guided prostate volume measurements in the Johns Hopkins active surveillance group and to establish whether or not this variability could affect prostate‐specific antigen density (PSAD) estimates in this cohort. PATIENTS AND METHODS: • In all, 253 patients with a combined total of 1111 prostate biopsies underwent TRUS‐guided prostate volume measurements performed by the same physician at least three times over the course of their care. • Coefficients of variation (CV) were calculated for each set of measurements performed on each patient by the same physician, and average CVs were determined for each physician and for physicians overall. The CVs were correlated with the average of each patient’s measured prostate volumes to look for any trend. • Finally, measured prostate volumes were used with each patient’s initial prostate‐specific antigen (PSA) value to calculate PSAD to reveal whether or not the degree of variability found in these measurements would have led to PSADs that would have otherwise precluded qualification for active surveillance. RESULTS: • The average CV for all sets of prostate volume data was 0.168. Average CVs for each physician ranged from 0.136 to 0.234. • However, actual CVs ranged anywhere from 0.013 to 0.549. The CVs were found to have no correlation with prostate volumes (Pearson correlation coefficient: 0.04). • In 95% of cases, variability in TRUS‐guided prostate volume measurement did not affect PSAD sufficiently to elicit a value greater than 0.15. CONCLUSIONS: • Even among individuals who are highly experienced in TRUS‐guided prostate volume measurement, significant intra‐observer variation exists. However, this variability is not enough to affect one’s eligibility for prostate cancer active surveillance when PSAD criteria are used. • The TRUS‐guided prostate volume measurements remain a reliable method of assessing PSAD in patients with prostate cancer.