Faculty Bibliography

Historically, the primary objection to partial gland ablation (PGA) for management of prostate cancer (CaP) has been disease multifocality and inability to localize significant disease. Improved disease localization and risk stratification with multiparametric magnetic resonance imaging and targeted biopsy, along with its minimal adverse impact on quality of life has enabled PGA to gain acceptance. Today, the primary barrier for adopting PGA is its unknown oncological outcomes. Objectives of this review are to provide a rationale for PGA for managing intermediate-risk (IR) CaP; review oncological outcomes following PGA for IR disease; and assess whether there is adequate data to justify PGA for management of IR CaP. There is no consensus how to assess or define oncological outcomes following PGA. We propose the following definitions for oncological outcomes: Oncological control (detection of any cancer following biopsy), oncological failure (detection of Gleason grade group >1 on follow-up biopsy), and oncological treatment failure (any disease that precipitate salvage treatment). There are only 3 reports in the literature where inclusion criteria specified pretreatment targeted biopsy and reflex prostate biopsy within 1 year of PGA in cohorts of men where >50% had Gleason grade group >1 disease. These studies reported that prostate-specific antigen is not a reliable surrogate and multiparametric magnetic resonance imaging is reliable when prevalence of in-field CaP is high. "Freedom from failure" is used to assess longer-term oncologic outcomes, and is defined by freedom from CaP mortality, androgen deprivation therapy, or whole-gland treatment. Rationale for PGA in selected cases of IR CaP is compelling and early oncological studies are reassuring. If patient selection is done judiciously, oncologic outcomes are disclosed, and follow-up plan is rigorously implemented, it is unlikely rates of metastasis or CaP mortality with be adversely impacted and many men will avoid or defer adverse effects of whole-gland treatment.

OBJECTIVES/OBJECTIVE:To compare both the concordance between the 4Kscore® and SelectMDx® for informing decision to perform prostate biopsy (PB) and the performance of these tests for detecting clinically significant prostate cancer (csPCa). Several biomarkers were developed to inform decisions whether to perform a PB based on the probability of detecting csPCa. There is a paucity of studies directly comparing them METHODS: Between 11/2018 and 4/2019, all new referrals with the diagnosis of elevated PSA were advised to undergo 4Kscore® and SelectMDx® in order to guide the selection of candidates for PB. Men were advised to undergo PB if the reported biomarker risk for detecting csPCA was ≥7.5%, or if they presented a PI-RADS ≥1 MRI. Cohen's Kappa was used to assess the concordance between the binary 4Kscore® and SelectMDx® results using externally validated cutoffs of 7.5% and 12%. Receiver operating characteristics curve and area under the curve (AUC) assessed the performance of each biomarker for predicting csPCa. RESULTS:Of 128 consecutive patients referred, 114 (89.1%) underwent 4Kscore® and SelectMDx®, The kappa coefficient between the biomarkers using the 7.5% cutoff was 0.184 (poor concordance) and 0.22 using the 12% cutoff. The two biomarkers yielded discordant guidance whether to proceed with PB in 46% and 38% of cases, respectively. csPCa was found in 22 of the 50 patients who underwent PB (44%). The AUC for 4Kscore® and SelectMDx® was 0.830 (95%CI: 0.710 - 0.949) and 0.672 (95%CI: 0.517 - 0.828) (p=0.036), respectively. CONCLUSION/CONCLUSIONS:The discordance observed between the 4Kscore® and SelectMDx® is disconcerting. The 4Kscore® when combined with MRI was superior to the SelectMDx® for detecting csPCa. Prospective comparative studies must be performed to optimize implementation of biomarkers for selecting candidates for PB.

Current guidelines recommend conservative management as the preferred option for most low-risk prostate cancer cases, with certain possible exceptions (age <55yr, African Americans, and high-volume grade group 1). Although previous studies have documented substantial heterogeneity in the uptake of conservative management, less is known about the underlying reason for this variation and whether it is due to guideline-concordant factors (age, race, and biopsy cancer volume). We explored variation in the use of conservative management for low-risk prostate cancer among 20 597 men diagnosed in the US Veterans Affairs health care system from 2010 to 2016. Conservative management increased substantially over this time from 51% to 76% (p< 0.001). However, there was substantial variation by facility (35-100%). Multivariable analysis revealed that patient factors included in the guidelines (e.g., age and biopsy cores), other patient factors (eg, marital status and PSA) and non-patient factors (eg, geographic region, case volume, year) were associated with conservative management use. In conclusion, even within an integrated health care system, there remains significant heterogeneity in the uptake of conservative management for low-risk prostate cancer. Both guideline-concordant factors and other factors not discussed in the guidelines were associated with conservative management use. PATIENT SUMMARY: In the US Veterans Affairs health care system the vast majority of men with low-risk prostate cancer were managed conservatively by 2016, although there was significant variation by facility. Patient factors specifically mentioned in guidelines had the greatest impact on prediction of conservative management.

We demonstrate the use of 5'-Acrydite oligonucleotides to copolymerize single-cell DNA or RNA into balls of acrylamide gel (BAG). Combining this step with split-and-pool techniques for creating barcodes yields a method with advantages in cost and scalability, depth of coverage, ease of operation, minimal cross-contamination and efficient use of samples. We perform DNA copy number profiling on mixtures of cell lines, nuclei from frozen prostate tumors, and biopsy washes. As applied to RNA, the method has high capture efficiency of transcripts and sufficient consistency to distinguish clearly the expression patterns of cell lines and individual nuclei from neurons dissected from the mouse brain. Using varietal tags (UMIs) to achieve sequence error correction, we show extremely low levels of cross-contamination by tracking source-specific SNVs. The method is readily modified, and we will discuss its adaptability and diverse applications.

BACKGROUND/PURPOSE/OBJECTIVE:Stratification of Gleason score (GS) into three categories (2-6, 7, and 8-10) may not fully utilize its prognostic discrimination, with Gleason pattern 5 (GP5) previously identified as an independent adverse factor. MATERIALS/METHODS/METHODS:Patients treated on RTOG 9202 (n = 1292) or RTOG 9902 (n = 378) were pooled and assessed for association of GS and GP5 on biochemical failure (BF), local failure (LF), distant metastasis (DM), and overall survival (OS). Fine and Gray's regression and cumulative incidence methods were used for univariate and multivariate analyses. RESULTS:With median follow-up of 9.4 years, patients with GS 8-10 with GP5 had worse outcome than GS 4 + 4 for DM on both RTOG9202 (p = 0.038) and RTOG9902 (p < 0.001) with a trend toward worse OS (p = 0.059 and p = 0.089, respectively), but without differences in BF or LF. At 10-years DM was higher by 11% (RTOG 9202) and 18% (RTOG 9902) with GP5 compared to GS 4 + 4. On multivariate analysis restricted to long-term androgen deprivation therapy the presence of GP5 substantially increased distant metastasis (HR = 0.43, 95%CI: 0.24-0.76, p = 0.0039) with a trend toward worse OS (HR:0.74, 95% CI:0.54-1.0, p = 0.052) without association with LF (HR:0.55, 95%CI:0.28-1.09, p = 0.085) or BF (HR:1.15, 95%CI:0.84-1.59, p = 0.39). We did not observed substantial differences between Gleason 3 + 5, 5 + 3, or Gleason 9-10. CONCLUSIONS:These results validate GP5 as an independent prognostic factor which is strongest for DM. As a result GP5 should be considered when stratifying patients with GS 8 and may be a patient population in which to evaluate newly approved systemic therapies or additional local treatments.

Electronic-cigarettes (E-cigs) are marketed as a safe alternative to tobacco to deliver the stimulant nicotine, and their use is gaining in popularity, particularly among the younger population. We recently showed that mice exposed to short-term (12 wk) E-cig smoke (ECS) sustained extensive DNA damage in lungs, heart, and bladder mucosa and diminished DNA repair in lungs. Nicotine and its nitrosation product, nicotine-derived nitrosamine ketone, cause the same deleterious effects in human lung epithelial and bladder urothelial cells. These findings raise the possibility that ECS is a lung and bladder carcinogen in addition to nicotine. Given the fact that E-cig use has become popular in the past decade, epidemiological data on the relationship between ECS and human cancer may not be known for a decade to come. In this study, the carcinogenicity of ECS was tested in mice. We found that mice exposed to ECS for 54 wk developed lung adenocarcinomas (9 of 40 mice, 22.5%) and bladder urothelial hyperplasia (23 of 40 mice, 57.5%). These lesions were extremely rare in mice exposed to vehicle control or filtered air. Current observations that ECS induces lung adenocarcinomas and bladder urothelial hyperplasia, combined with our previous findings that ECS induces DNA damage in the lungs and bladder and inhibits DNA repair in lung tissues, implicate ECS as a lung and potential bladder carcinogen in mice. While it is well established that tobacco smoke poses a huge threat to human health, whether ECS poses any threat to humans is not yet known and warrants careful investigation.

BACKGROUND:In prostate cancer, end points that reliably portend prognosis and treatment benefit (surrogate end points) can accelerate therapy development. Although surrogate end point candidates have been evaluated in the context of radiotherapy and short-term androgen deprivation (AD), potential surrogates under long-term (24 month) AD, a proven therapy in high-risk localized disease, have not been investigated. MATERIALS AND METHODS/METHODS:In the NRG/RTOG 9202 randomized trial (N = 1,520) of short-term AD (4 months) versus long-term AD (LTAD; 28 months), the time interval free of biochemical failure (IBF) was evaluated in relation to clinical end points of prostate cancer-specific survival (PCSS) and overall survival (OS). Survival modeling and landmark analysis methods were applied to evaluate LTAD benefit on IBF and clinical end points, association between IBF and clinical end points, and the mediating effect of IBF on LTAD clinical end point benefits. RESULTS:LTAD was superior to short-term AD for both biochemical failure (BF) and the clinical end points. Men remaining free of BF for 3 years had relative risk reductions of 39% for OS and 73% for PCSS. Accounting for 3-year IBF status reduced the LTAD OS benefit from 12% (hazard ratio [HR], 0.88; 95% CI, 0.79 to 0.98) to 6% (HR, 0.94; 95% CI, 0.83 to 1.07). For PCSS, the LTAD benefit was reduced from 30% (HR, 0.70; 95% CI, 0.52 to 0.82) to 6% (HR, 0.94; 95% CI, 0.72 to 1.22). Among men with BF, by 3 years, 50% of subsequent deaths were attributed to prostate cancer, compared with 19% among men free of BF through 3 years. CONCLUSION/CONCLUSIONS:The IBF satisfied surrogacy criteria and identified the benefit of LTAD on disease-specific survival and OS. The IBF may serve as a valid end point in clinical trials and may also aid in risk monitoring after initial treatment.

The number of solid organ transplantations is increasing worldwide. Major medical advances have allowed for incremented survival in this population, which, because approximately 50% of recipients are over age 50 years, makes for an increasingly older population of transplant survivors. This article discusses controversies and current guidelines related to prostate cancer (PCa) screening, detection, and treatment for men in the general population. The relevant literature is reviewed in order to provide insights on how to optimize PCa screening, detection, and treatment pre- and post-solid organ transplantation. There is compelling evidence that immunosuppression does not increase the risk for the development or progression of PCa following solid organ transplantation. Therefore, PCa screening, detection, or treatment should not be influenced by the impact of immunosuppression on the biology of the disease. Prostate-specific antigen (PSA) appears to be as reliable for PCa screening of transplant candidates and recipients as it is for the general population. There is no consensus on how or when it should be implemented. Evidence is also equivocal as to the suggested waiting time between treatment and transplantation. Surgery and radiation therapy appear to be safe and provide good outcomes for managing PCa in solid organ transplant candidates and recipients. However, certain precautions should be taken with this vulnerable population, especially for kidney transplant patients given the pelvic location of the renal graft. Partial gland ablation of PCa should be considered in appropriate candidates.