Occult High-risk Disease in Clinically Low-risk Prostate Cancer with ≥50% Positive Biopsy Cores: Should National Guidelines Stop Calling Them Low Risk?

Use of Decipher Prostate Biopsy Test in Patients with Favorable-risk Disease Undergoing Conservative Management or Radical Prostatectomy in the Surveillance, Epidemiology, and End Results Registry

BACKGROUND AND OBJECTIVE

The extent of prostate cancer found on biopsy, as well as prostate cancer grade and genomic tests, can affect clinical decision-making. The impact of these factors on the initial management approach and subsequent patient outcomes for men with favorable-grade prostate cancer has not yet been determined on a population level. Our objective was to explore the association of Decipher 22-gene genomic classifier (GC) biopsy testing on the initial use of conservative management versus radical prostatectomy (RP) and to determine the independent effect of GC scores on RP pathologic outcomes.

METHODS

A total of 87 140 patients diagnosed with grade group 1 and 2 prostate cancer between 2016 and 2018 from the Surveillance, Epidemiology, and End Results registry data were linked to GC testing results (2576 tested and 84 564 untested with a GC). The primary endpoints of interest were receipt of conservative management or RP, pathologic upgrading (pathologic grade group 3-5), upstaging (pathologic ≥T3b), and adverse pathologic features (pathologic upgrading, upstaging, or lymph node invasion). Multivariable logistic regressions quantified the association of variables with outcomes of interest.

KEY FINDINGS AND LIMITATIONS

GC tested patients were more likely to have grade group 2 on biopsy (51% vs 46%, p < 0.001) and lower prostate-specific antigen (6.1 vs 6.3, p = 0.016). Conservative management increased from 37% to 39% and from 22% to 24% during 2016-2018 for the GC tested and untested populations, respectively. GC testing was significantly associated with increased odds of conservative management (odds ratio [OR] 2.1, 95% confidence interval [CI] 1.9-2.4, p < 0.001). The distribution of biopsy GC risk was as follows: 45% low risk, 30% intermediate risk, and 25% high risk. In adjusted analyses, higher GC (per 0.1 increment) scores (OR 1.24, 95% CI 1.17-1.31, p < 0.001) and percent positive cores (1.07, 95% CI 1.02-1.12, p = 0.009) were significantly associated with the receipt of RP. A higher GC score was significantly associated with all adverse outcomes (pathologic upgrading [OR 1.29, 95% CI 1.12-1.49, p < 0.001], upstaging [OR 1.31, 95% CI 1.05-1.62, p = 0.020], and adverse pathology [OR 1.27, 95% CI 1.12-1.45, p < 0.001]). Limitations include observational biases associated with the retrospective study design.

CONCLUSIONS AND CLINICAL IMPLICATIONS

Men who underwent GC testing were more likely to undergo conservative management. GC testing at biopsy is prognostic of adverse pathologic outcomes in a large population-based registry.

PATIENT SUMMARY

In this population analysis of men with favorable-risk prostate cancer, those who underwent genomic testing at biopsy were more likely to undergo conservative management. Of men who initially underwent radical prostatectomy, higher genomic risk but not tumor volume was associated with adverse pathologic outcomes. The use of genomic testing at prostate biopsy improves risk stratification and may better inform treatment decisions than the use of tumor volume alone.

Prostate Cancer Tumor Volume and Genomic Risk

Background

Despite the historic association of higher prostate cancer volume with worse oncologic outcomes, little is known about the impact of tumor volume on cancer biology.

Objective

To characterize the relationship between tumor volume (measured by percent positive cores [PPC]) and cancer biology (measured by Decipher genomic risk classifier [GC]) in men who underwent prostate biopsy.

Design setting and participants

Prostate biopsies from 52 272 men profiled with Decipher captured in a population-based prospective tumor registry were collected from 2016 to 2021.

Outcome measurements and statistical analysis

The degree of distribution and correlation of PPC with a GC score across grade group (GG) strata were examined using the Mann-Whitney U test, Pearson correlation coefficient, and multivariable linear regression controlled for clinicopathologic characteristics.

Results and limitations

A total of 38 921 (74%) biopsies passed quality control (14 331 GG1, 16 159 GG2, 5661 GG3, 1775 GG4, and 995 GG5). Median PPC and GC increased with sequentially higher GG. There was an increasingly positive correlation (r) between PPC and GC in GG2-5 prostate cancer (r [95% confidence interval {CI}]: 0.07 [0.5, 0.8] in GG2, 0.15 [0.12, 0.17] in GG3, 0.20 [0.15, 0.24] in GG4, and 0.25 [0.19, 0.31] in GG5), with no correlation in GG1 disease (r = 0.01, 95% CI [-0.001, 0.03]). In multivariable linear regression, GC was significantly associated with higher PPC for GG2-5 (all p < 0.05) but was not significantly associated with PPC for GG1. Limitations include retrospective design and a lack of final pathology from radical prostatectomy specimens.

Conclusions

Higher tumor volume was associated with worse GC for GG2-5 prostate cancer, whereas tumor volume was not associated with worse GC for GG1 disease. The finding that tumor volume is not associated with worse cancer biology in GG1 disease encourages active surveillance for most patients irrespective of tumor volume.

Patient summary

We studied the relationship between prostate cancer tumor volume and cancer biology, as measured by the Decipher genomic risk score, in men who underwent prostate biopsy. We found that tumor volume was not associated with worse cancer biology for low-grade prostate cancer. Our findings reassuringly support recent guidelines to recommend active surveillance for grade group 1 prostate cancer in most patients, irrespective of tumor volume.

Grade and stage misclassification in intermediate unfavorable-risk prostate cancer radiotherapy candidates

BACKGROUND

We tested for upgrading (Gleason grade group [GGG] ≥ 4) and/or upstaging to non-organ-confined stage ([NOC] ≥ pT3/pN1) in intermediate unfavorable-risk (IU) prostate cancer (PCa) patients treated with radical prostatectomy, since both change the considerations for dose and/or type of radiotherapy (RT) and duration of androgen deprivation therapy (ADT).

METHODS

We relied on Surveillance, Epidemiology, and End Results (2010-2015). Proportions of (a) upgrading, (b) upstaging, or (c) upgrading and/or upstaging were tabulated and tested in multivariable logistic regression models.

RESULTS

We identified 7269 IU PCa patients. Upgrading was recorded in 479 (6.6%) and upstaging in 2398 (33.0%), for a total of 2616 (36.0%) upgraded and/or upstaged patients, who no longer fulfilled the IU grade and stage definition. Prostate-specific antigen, clinical stage, biopsy GGG, and percentage of positive cores, neither individually nor in multivariable logistic regression models, discriminated between upgraded and/or upstaged patients versus others.

CONCLUSIONS

IU PCa patients showed very high (36%) upgrading and/or upstaging proportion. Interestingly, the overwhelming majority of those were upstaged to NOC. Conversely, very few were upgraded to GGG ≥ 4. In consequence, more than one-third of IU PCa patients treated with RT may be exposed to suboptimal dose and/or type of RT and to insufficient duration of ADT, since their true grade and stage corresponded to high-risk PCa definition, instead of IU PCa. Data about magnetic resonance imaging were not available but may potentially help with better stage discrimination.

Risk of adverse pathological features for intermediate risk prostate cancer: Clinical implications for definitive radiation therapy

BACKGROUND

Intermediate risk prostate cancer represents a largely heterogeneous group with diverse disease extent. We sought to establish rates of adverse pathological features important for radiation planning by analyzing surgical specimens from men with intermediate risk prostate cancer who underwent immediate radical prostatectomy, and to define clinical pathologic features that may predict adverse outcomes.

MATERIALS AND METHODS

A total of 1552 men diagnosed with intermediate risk prostate cancer who underwent immediate radical prostatectomy between 1/1/2005 and 12/31/2015 were reviewed. Inclusion criteria included available preoperative PSA level, pathology reports of transrectal ultrasound-guided prostate biopsy, and radical prostatectomy. Incidences of various pathological adverse features were evaluated. Patient characteristics and clinical disease features were analyzed for their predictive values.

RESULTS

Fifty percent of men with high risk features (defined as PSA >10 but <20 or biopsy primary Gleason pattern of 4) had pathological upstage to T3 or higher disease. The incidence of upgrade to Gleason score of 8 or higher and the incidence of lymph node positive disease was low. Biopsy primary Gleason pattern of 4, and PSA greater than 10 but less than 20, affected adverse pathology in addition to age and percent positive biopsy cores. Older age and increased percentage of positive cores were significant risk factors of adverse pathology.

CONCLUSION

Our findings underscore the importance of comprehensive staging beyond PSA level, prostate biopsy, and CT/bone scan for men with intermediate risk prostate cancer proceeding with radiation in the era of highly conformal treatment.

Prostate Cancer, Version 2.2019, NCCN Clinical Practice Guidelines in Oncology

The NCCN Guidelines for Prostate Cancer include recommendations regarding diagnosis, risk stratification and workup, treatment options for localized disease, and management of recurrent and advanced disease for clinicians who treat patients with prostate cancer. The portions of the guidelines included herein focus on the roles of germline and somatic genetic testing, risk stratification with nomograms and tumor multigene molecular testing, androgen deprivation therapy, secondary hormonal therapy, chemotherapy, and immunotherapy in patients with prostate cancer.

Impact of percent positive biopsy cores on cancer-specific mortality for patients with high-risk prostate cancer

OBJECTIVE

A high percent positive biopsy cores (PBC), typically dichotomized at ≥50% is prognostic of worse cancer-specific outcomes for patients with low- and intermediate-risk prostate cancer (CaP). The clinical significance of ≥50% PBC for patients with high-risk disease is poorly understood. We examined the association between ≥50% PBC, compared to <50% PBC, and prostate cancer-specific mortality (PCSM) for patients with high-risk disease.

MATERIALS AND METHODS

We identified 7,569 men from the Surveillance, Epidemiology, and End Results program who were diagnosed with high-risk CaP (Gleason score of 8-10, prostate-specific antigen >20 ng/mL, or cT3-T4 stage) in 2010-2011 and had 6 to 24 cores sampled at biopsy. Multivariable Fine and Gray competing risks regression was utilized to examine the association between ≥50% PBC and PCSM.

RESULTS

Median follow-up was 3.8 years. 56.2% of patients (4,253) had ≥50% PBC. On competing risks regression, ≥50% PBC was associated with a significantly higher risk of PCSM compared to <50% PBC (adjusted hazard ratio [AHR] 2.00, 95% confidence interval [CI] 1.48-2.70, P < 0.001). On subgroup analyses, ≥50% PBC was associated with a significantly higher risk of PCSM only for cT1-T2 disease (AHR 2.23, 95% CI 1.62-3.07) but not cT3-T4 disease (AHR 0.83, 95% CI 0.39-1.76), with a significant interaction (P_interaction = 0.016). No significant interactions by Gleason score, prostate-specific antigen level, use of definitive therapy, or number of biopsy cores sampled were observed.

CONCLUSION

In this large cohort of patients with high-risk CaP, ≥50% PBC was independently associated with an approximately 2-fold increased risk of PCSM for patients with cT1-T2, but not cT3-T4, tumors. Percent PBC, which is a widely available clinical value, should be routinely used to risk stratify men with high-risk disease and identify patients whom may benefit from treatment intensification.

Dissecting the heterogeneity of localized prostate cancer risk groups through integration of percent of positive cores

AIM

To develop a modified risk stratification scheme for localized prostate cancer incorporating percent of positive cores (PPC).

METHODS

SEER database was accessed for eligible patients. Assessment of the prognostic value of PPC was conducted in a multivariate Cox regression model. A modified risk stratification scheme was proposed.

RESULTS

In a multivariate model, higher PPC was associated with worse cancer-specific survival (p < 0.0001). A modified risk-stratification scheme was proposed incorporating PPC. Concordance index was evaluated and the results were: D'Amico model: 0.782 (SE: 0.014; 95% CI: 0.755-0.810); modified model: 0.809 (SE: <0.001; 95% CI: 0.781-0.837).

CONCLUSION

Integration of PPC into the risk stratification model for localized prostate cancer improves its performance.

Comparative effectiveness in urology: a state of the art review utilizing a systematic approach

PURPOSE OF REVIEW

Comparative effectiveness research plays a vital role in healthcare delivery by guiding evidence-based practices. We performed a state-of-the-art review of comparative effectiveness research in the urology literature for 2016, utilizing a systematic approach. Seven high-impact papers are reviewed in detail.

RECENT FINDINGS

Across the breadth of urology, there were several important studies in comparative effectiveness research, of which we will highlight two randomized controlled trials and five observational trials: radiotherapy, prostatectomy, and active monitoring have equivalent mortality outcomes in patients with localized prostate cancer; the ideal modality of patient education is yet to be determined, and written education has minimal effect on patient perception of prostate specific antigen screening; robotic prostatectomy is associated with higher perioperative complication rates on a population basis; racial disparities exist in incontinence rates after treatment for localized prostate cancer, but not in irritative, bowel, or sexual function; androgen deprivation therapy is associated with higher fracture, peripheral artery disease, and cardiac-related complications than bilateral orchiectomy; robotic and open cystectomy offer comparable cancer-specific mortality and perioperative outcomes; and bonuses for low-cost hospitals can inadvertently reward low-quality hospitals.

SUMMARY

There have been major advancements in comparative effectiveness research in urology in 2016.

3+4 = 6? Implications of the stratification of localised Gleason 7 prostate cancer by number and percentage of positive biopsy cores in selecting patients for active surveillance

OBJECTIVE

To determine whether the number and percentage of positive biopsy cores identify a Gleason 3+4 prostate cancer (PC) subgroup of similar biologic behaviour to Gleason 3+3.

MATERIAL AND METHOD

An observational post-radical prostatectomy study was conducted of a cohort of 799 patients with localised low-risk (n=582, Gleason 6, PSA <10ng/ml and cT1c-2a) and favourable intermediate PC (n=217, Gleason 3+4, PSA ≤10 ng/ml and pT2abc). The Gleason 3+4 tumours were stratified by number (≤3 vs.>3) and by percentage of positive cores (≤33% vs. >33%). We analysed the tumours' association with the biochemical recurrence risk (BRR) and cancer-specific mortality (CSM). We conducted various predictive models using Cox regression and estimated (C-index) and compared their predictive capacity.

RESULTS

With a median follow-up of 71 months, the BRR and CSM of the patient group with Gleason 3+4 tumours and a low number (≤3) and percentage (≤33%) of positive cores were not significantly different from those of the patients with Gleason 6 tumours. At 5 and 10 years, there were no significant differences in the number of biochemical recurrences, the probability of remaining free of biochemical recurrences, the number of deaths by PC or the probability of death by PC between the 2 groups. In contrast, the patients with Gleason 3+4 tumours and more than 33% of positive cores presented more deaths by PC than the patients with Gleason 6 tumours. At 10 years, the probability of CSM was significantly greater. This subgroup of tumours showed a significantly greater BRR (RR, 1.6; P=.02) and CSM (RR, 5.8, P≤.01) compared with the Gleason 6 tumours. The model with Gleason 3+4 stratified by the percentage of positive cores significantly improved the predictive capacity of BRR and CSM.

CONCLUSIONS

Fewer than 3 cores and a percentage <33% of positive cores identifies a subgroup of Gleason 3+4 tumours with biological behaviour similar to Gleason 6 tumours. At 10 years, there were no differences in BRR and CSM between the 2 groups. These results provide evidence supporting active surveillance as an alternative for Gleason 3+4 tumours and low tumour extension in biopsy.

Optimization of Risk Stratification in Localized Prostate Cancer

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors’ suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice.

A 67-year-old retired engineering professor was found to have a prostate-specific antigen (PSA) level of 11 ng/mL on a screening test at his annual physical examination. A digital rectal examination revealed a nodule on the right side. He underwent a transrectal ultrasound-guided prostate biopsy that was notable for prostate adenocarcinoma, Gleason 3 + 4 = 7 (Gleason grade group 2; 30% Gleason 4 component) involving two cores (60% and 20% core involvement). A bone scan and pelvic computed tomography scan were negative for evidence of metastatic disease. (Should he undergo prostate magnetic resonance imaging? That seems rather common these days.) He was diagnosed with cT2b intermediate-risk localized prostate cancer (PCa) by National Comprehensive Cancer Network (NCCN) risk group and was seen in the multidisciplinary clinic to discuss management options (Table 1).

Favorable Gleason 3 + 4 Prostate Cancer Shows Comparable Outcomes With Gleason 3 + 3 Prostate Cancer: Implications for the Expansion of Selection Criteria for Active Surveillance

BACKGROUND

To investigate the feasibility of active surveillance (AS) in biopsy Gleason score (GS) 3 + 4 prostate cancer (PCa), we compared the outcomes of biopsy GS 3 + 3 and 3 + 4 PCa after radical prostatectomy.

PATIENTS AND METHODS

We analyzed the data of 1491 patients undergoing radical prostatectomy for biopsy GS 3 + 3 or 3 + 4 PCa who fulfilled the low-risk criteria of the National Comprehensive Cancer Network guidelines regardless of GS. The favorable GS 3 + 4 group was defined as having core involvement ≤ 50%, prostate-specific antigen density ≤ 0.2 ng/mL/cm³, and number of positive cores ≤ 2 (maximal 1 core of GS 3 + 4).

RESULTS

The GS 3 + 4 group showed significantly worse pathologic outcomes, including pathologic GS, pathologic stage, and seminal vesicle invasion rate (all P < .001), as well as worse biochemical recurrence-free survival (P < .001) than the GS 3 + 3 group. However, the favorable GS 3 + 4 subgroup showed no significant differences in the pathologic outcomes (all P > .05) and in biochemical recurrence-free survival (P = .817) compared to the GS 3 + 3 group.

CONCLUSION

Despite the application of low-risk criteria, GS 3 + 4 PCa patients showed significantly worse outcomes than GS 3 + 3 patients. However, favorable GS 3 + 4 patients showed comparable clinicopathologic outcomes with GS 3 + 3 patients, suggesting possible expansion of AS for the favorable GS 3 + 4 group.

Diffusion-weighted endorectal MR imaging at 3T for prostate cancer: correlation with tumor cell density and percentage Gleason pattern on whole mount pathology

OBJECTIVE

To determine if tumor cell density and percentage of Gleason pattern within an outlined volumetric tumor region of interest (TROI) on whole-mount pathology (WMP) correlate with apparent diffusion coefficient (ADC) values on corresponding TROIs outlined on pre-operative MRI.

METHODS

Men with biopsy-proven prostate adenocarcinoma undergoing multiparametric MRI (mpMRI) prior to prostatectomy were consented to this prospective study. WMP and mpMRI images were viewed using 3D Slicer and each TROI from WMP was contoured on the high b-value ADC maps (b0, 1400). For each TROI outlined on WMP, TCD (tumor cell density) and the percentage of Gleason pattern 3, 4, and 5 were recorded. The ADC_mean, ADC_{10th percentile}, ADC_{90th percentile}, and ADC_ratio were also calculated in each case from the ADC maps using 3D Slicer.

RESULTS

Nineteen patients with 21 tumors were included in this study. ADC_mean values for TROIs were 944.8 ± 327.4 vs. 1329.9 ± 201.6 mm²/s for adjacent non-neoplastic prostate tissue (p < 0.001). ADC_mean, ADC_{10th percentile}, and ADC_ratio values for higher grade tumors were lower than those of lower grade tumors (mean 809.71 and 1176.34 mm²/s, p = 0.014; 10th percentile 613.83 and 1018.14 mm²/s, p = 0.009; ratio 0.60 and 0.94, p = 0.005). TCD and ADC_mean (ρ = -0.61, p = 0.005) and TCD and ADC_{10th percentile} (ρ = -0.56, p = 0.01) were negatively correlated. No correlation was observed between percentage of Gleason pattern and ADC values.

CONCLUSION

DWI MRI can characterize focal prostate cancer using ADC_ratio, ADC_{10th percentile}, and ADC_mean, which correlate with pathological tumor cell density.

Weighing Risk of Cardiovascular Mortality Against Potential Benefit of Hormonal Therapy in Intermediate-Risk Prostate Cancer

Background

The purpose of this study is to determine the optimal strategy for men with newly diagnosed intermediate-risk prostate cancer by age and cardiac risk.

Methods

A Markov model was calibrated to the EORTC 22991 trial, which randomly assigned men with intermediate-risk prostate cancer to radiation therapy (RT) with or without six months of hormonal therapy (HT). We compared quality-adjusted life-years (QALYs) in men age 50, 60, and 70 years by age decile and cardiac risk group. Competing risks of cardiovascular mortality were estimated from the published literature. Sensitivity analyses were used to assess the impact of varying model assumptions.

Results

HT was associated with a net decrease of 0.3 to 0.4 QALYs in men with a history of myocardial infarction. However, for all other men, HT improved QALYs (range = 0.4-2.6 QALYs). Younger men with fewer cardiac risk factors experienced the largest benefit from HT. In sensitivity analyses, the model was only found to be sensitive to the probability of biochemical failure. Men at low risk for biochemical failure (≤8.7% at five years) did not benefit from HT. Further, the benefits of HT did not begin to manifest until after 7.3 years of follow-up.

Conclusions

The optimal choice of therapy depends upon age, cardiac risk, and disease recurrence risk. Young men with intermediate-risk prostate cancer with no cardiac risk factors benefit most from HT. Men with a history of myocardial infarction who are at very low risk for biochemical failure may be negatively impacted by the addition of HT.

Active surveillance for intermediate-risk prostate cancer

Background

Utilization of active surveillance (AS) for prostate cancer is increasing. Optimal selection criteria for this approach are undefined and questions remain on how best to expand inclusion beyond typical men with very low or low risk disease. We sought to review the current experience with AS for men with intermediate risk features.

Methods

Pubmed was queried for all relevant original publications describing outcomes for men with prostate cancer managed with AS. Outcomes for patients with intermediate risk features as defined by the primary investigators were studied when available and compared with similar risk men undergoing immediate treatment.

Results

Cancer specific survival for men managed initially with AS is similar to results published with immediate radical intervention. A total of 5 published AS series describe some outcomes for men with intermediate risk features. Definitions of intermediate risk vary between studies. Men with Gleason 7 disease experience higher rates of clinical progression and are more likely to undergo treatment over time. Intermediate risk men with Gleason 6 disease have similar outcomes to low risk men. Men with Gleason 7 disease appear at higher risk for metastatic disease. Novel technologies including imaging and biomarkers may assist with patient selection and disease surveillance.

Conclusions

The contemporary experiences of AS for men with intermediate risk features suggest that although these men are at higher risk for eventual prostate directed treatment, some are not significantly compromising chances for longer-term cure. Men with more than minimal Gleason pattern 4, however, must be carefully selected and surveyed for early signs of progression and may be at increased risk of metastases. Incorporating information from advanced imaging and biomarker technology will likely individualize future treatment decisions while improving overall surveillance strategies.

Incorporating Androgen Deprivation With Dose-Escalated External-Beam Radiotherapy for Prostate Cancer

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors' suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice.A 71-year-old man was seen by his primary care physician for routine evaluation in early 2015. On digital rectal examination, his prostate was moderately enlarged, although he had no obvious areas of palpable disease. His prostate-specific antigen (PSA) level was 7.1 ng/mL. A standard ultrasound-guided biopsy of his prostate revealed a 60-mL prostate volume and a single core (out of 12) of Gleason 3 + 3 disease. He chose to undergo surveillance. Six months later, his PSA level had risen to 10.0 ng/mL; there was still no palpable disease on digital rectal examination. Multiparametric magnetic resonance imaging of his prostate and pelvis revealed two suspicious intraprostatic lesions with restricted diffusion, focal and earlier enhancement with contrast than adjacent normal prostate, and hypointense features on T2-weighted imaging; these findings were highly suspicious for high-grade prostate cancer (Fig 1). Magnetic resonance imaging-ultrasound fusion targeted biopsy of each lesion yielded a total of four positive biopsy cores of Gleason 4 + 3 = 7, involving 50% to 80% of each core, with perineural invasion noted. The patient's medical history is notable for overweight (but not morbidly obese), hypercholesterolemia, hypertension, cataract surgeries, and inguinal hernia repair, but the patient is otherwise healthy. He has decided against prostatectomy and brachytherapy because of strong personal preference. In particular, he wanted to avoid anesthesia, and was concerned about the potential for greater urinary incontinence and/or urinary irritation associated with these treatments compared with external-beam radiotherapy (RT).(1,2).