Oncological and urinary outcomes following low-dose-rate brachytherapy with a median follow-up of 11.8 years.

OBJECTIVES: To examine the long-term oncological outcomes and urological morbidity of low-dose-rate prostate brachytherapy (LDRBT) monotherapy using live intraoperative dosimetry planning and an automated needle navigation delivery system for the treatment of men with low and intermediate-risk prostate cancer. PATIENTS AND METHODS: A prospective database of 400 consecutive patients who underwent LDRBT between July 2003 and June 2015 was retrospectively reviewed to assess urinary side-effects and biochemical progression, based on the Phoenix definition and also a definition of a prostate-specific antigen (PSA) level of ≥0.2 µg/L. RESULTS: Minimum patient follow-up was 5.5 years. The median follow-up of the entire cohort was 11.8 years. The median (range) PSA level was 6.1 (0.9-17) µg/L and the median Gleason score was 3 + 4. The biochemical relapse-free survival (RFS; freedom from biochemical recurrence) based on the Phoenix definition was 85.8% (343/400). The RFS using a 'surgical' definition of a PSA level of <0.2 µg/L was 71% (284/400). Of the 297 men followed for ≥10 years, prostate cancer-specific survival (PCSS) was 98% (291/297). Post-LDRBT urethral stricture developed in 11 men (2.8%, 11/400). For men with ≥10 years of follow-up, 22 men (7.4%, 22/297) required a pad for either stress or urge urinary incontinence (UI). UI was identified in only 2.2% (one of 46) of men who had a bladder neck incision (BNI) before LDRBT. CONCLUSION: LDRBT is associated with excellent PCSS, with a median follow-up of 11.8 years. The risk of post-implantation urethral stricture and UI is low and a pre-implantation BNI for management of bladder outflow obstruction does not increase the risk of UI or urethral stricture.

The use of 68Ga-PET/CT PSMA to determine patterns of disease for biochemically recurrent prostate cancer following primary radiotherapy.

BACKGROUND: 68Ga-PET/CT PSMA scan is being increasingly used for the staging of biochemically recurrent disease. Early identification of recurrent disease after radiotherapy is important in considering suitability for early salvage therapy to improve prognosis. The aim is to identify patterns of suspected prostate cancer recurrence in relation to post-radiotherapy PSA levels, especially below the accepted Phoenix definition of PSA failure (PSA nadir + 2). METHODS: This was a retrospective single tertiary institution cohort study of consecutive men between July 2014 and June 2018 who received a 68Ga-PSMA PET/CT for elevated PSA levels following radiotherapy as primary treatment of prostate cancer. The primary outcome measure was to determine the relationship between pre-scan PSA and the probability of identifying PSMA-avid disease suggestive of recurrent prostate cancer. RESULTS: Two hundred and seventy-six patients met criteria for inclusion. The median PSA was 3.60 ng/mL. The overall detection rate for suspected recurrent prostate cancer was 86.3%. Local recurrence was the most common site, occurring in 56.9% (157/276) of men, with isolated local recurrence in 32.6% (90/276). A total of 75.3% (55/73) of men below Phoenix criteria had scans suggestive of recurrent disease, with 52.1% of men having salvageable disease. The regions surrounding the iliac arteries were the most common areas of nodal metastatic disease, with 55.6% of recurrence occurring in the iliac regions. CONCLUSIONS: 68Ga-PSMA PET/CT frequently identifies suspected recurrent disease prior to the accepted Phoenix definition of PSA nadir +2. Prospective outcome studies are required to determine if early identification of local recurrence improves outcomes by increasing the use of salvage local treatments and whether earlier identification of metastatic disease may improve outcomes with prompt initiation of multimodality therapies.

Health-related quality of life after single-fraction high-dose-rate brachytherapy and hypofractionated external beam radiotherapy for prostate cancer.

PURPOSE: To investigate the change in health-related quality of life for men after high-dose-rate brachytherapy and external beam radiotherapy for prostate cancer and the factors associated with this change. METHODS AND MATERIALS: Eligible patients had clinically localized intermediate-risk prostate cancer. The patients received high-dose-rate brachytherapy as a single 15-Gy implant, followed by external beam radiotherapy to 37.5 Gy in 15 fractions. The patients were monitored prospectively for toxicity (Common Terminology Criteria for Adverse Events, version 3.0) and health-related quality of life (Expanded Prostate Cancer Index Composite [EPIC]). The proportion of patients developing a clinically significant difference in the EPIC domain score (minimally important difference of >0.5 standard deviation) was determined and correlated with the baseline clinical and dosimetric factors. The study accrued 125 patients, with a median follow-up of 24 months. RESULTS: By 24 months, 23% had Grade 2 urinary toxicity and only 5% had Grade 2 bowel toxicity, with no Grade 3 toxicity. The proportion of patients reporting a significant decrease in EPIC urinary, bowel, sexual, and hormonal domain scores was 53%, 51%, 45%, and 40% at 12 months and 57%, 65%, 51%, and 30% at 24 months, respectively. The proportion with a >1 standard deviation decrease in the EPIC urinary, bowel, sexual, and hormonal domain scores was 38%, 36%, 24%, and 20% at 12 months and 46%, 48%, 19%, and 8% at 24 months, respectively. On multivariate analysis, the dose to 10% of the urethra was associated with a decreasing EPIC urinary domain score (p = .0089) and, less strongly (p = .0312) with a decreasing hormonal domain score. No association was found between the prostate volume, bladder dose, or high-dose volume and urinary health-related quality of life. A high baseline International Index of Erectile Function score was associated (p = .0019) with a decreasing sexual domain score. The optimal maximal dose to 10% of the urethra cutpoint for urinary health-related quality of life was 120% of the prescription dose. CONCLUSION: EPIC was a more sensitive tool for detecting the effects on function and bother than were the generic toxicity scales. The urethral dose had the strongest association with a deteriorating urinary quality of life.