Clinical and treatment characteristics of secondary bladder malignancies following low dose rate brachytherapy for prostate cancer.

PURPOSE/OBJECTIVES: To characterize the clinical course and prognosis of bladder malignancies associated with prior prostate brachytherapy SUBJECTS/PATIENTS AND METHODS: We queried our institutional database for patients with bladder cancer (BC) diagnosed between January 2005 and April 2019 who had previously undergone low dose rate (LDR) prostate brachytherapy. Patients diagnosed with BC at least 1 year following LDR prostate brachytherapy with or without external beam radiation therapy were included. Clinical and disease-specific characteristics were abstracted from chart review and survival outcomes were estimated using Kaplan-Meier estimates. We compared the pathologic characteristics and prognosis of secondary BCs in our study cohort to those of BCs diagnosed after prostate cancer managed without radiation reported by the Surveillance, Epidemiology, and End Results (SEER) populational database from 2005 to 2018. RESULTS: Three hundred seventy-five patients were identified with combined diagnosis of prostate cancer and BC, 51 of whom met inclusion criteria in the study cohort. Median times from brachytherapy to BC diagnosis for the study and SEER cohort were 9.5 ± 4.5 and 6.3 ± 4.1 years, respectively. Compared to the SEER cohort, significantly greater proportion of BC from the study cohort presented with high-grade (study: 78.4%, SEER: 52.3%, P = 0.0008) and with MIBC (Study BC 35.3%, SEER BC: 17.5%, P = 0.0009). The study and the SEER cohort had similar 5-year overall survival (study: 67.9%, SEER: 58.0%, P = 0.1099), and 5-year cancer-specific survival (study: 81.0%, SEER: 82.8%, P = 0.5559). The 5-year progression-free survival for the study cohort was 43.7% (95% CI: 28.8-57.7). CONCLUSION: Compared to bladder cancers following prostate cancer managed without radiation, bladder malignancies following prostate LDR brachytherapy present with higher grade and are more likely to be muscle invasive. Despite the aggressive presenting features of postprostate brachytherapy BC, there were no differences in overall and cancer-specific survival between the groups.

Salvage low dose rate brachytherapy for prostate cancer recurrence following definitive external beam radiation therapy.

PURPOSE: We sought to describe the safety and efficacy of salvage low dose rate (LDR) brachytherapy for local prostate cancer recurrence following definitive RT. MATERIALS AND METHODS: We included patients from two prospectively maintained institutional databases who underwent salvage LDR brachytherapy for biopsy confirmed intra-prostatic recurrence following primary RT. All patients were without evidence of metastatic disease. Freedom from biochemical failure (FFbF), prostate cancer specific survival (PCaSS), and overall survival (OS) were determined using the Kaplan-Meier estimates. Cox proportional hazard models were used to identify factors predictive of FFbF. Toxicity was graded by Common Terminology Criteria for Adverse Events (CTCAE) v5.0. RESULTS: 108 patients were included. Median follow-up was 6.3 years. The 5- and 10-year actuarial survival outcomes were as follows: FFbF, 63.1% and 52.0%; PCaSS, 90.5% and 77.8%; OS, 80.9% and 56.7%. On multivariate modeling, increasing grade group (HR 1.41, 95% CI 1.02-1.95, p = 0.036) and initial PSA at diagnosis (HR 1.02, 95% CI 1.004-1.05, p = 0.022) were associated with worse FFbF. Grade 3 toxicity occurred in 16.7% of patients; including genitourinary events in 15.7% and gastrointestinal events in 2.8% of patients. IPSS scores increased following implant, peaking at 2 months (median IPSS 20, p = 0.002) and thereafter remaining elevated throughout follow-up. CONCLUSIONS: Salvage LDR brachytherapy is safe and efficacious, with acceptable grade 3+ toxicity and good biochemical control on long-term follow-up. Patients with higher grade group and higher PSA at initial diagnosis may be at increased risk for biochemical failure.

Initial results of a randomized phase III trial of high dose image guided radiation with or without androgen deprivation therapy for intermediate-risk prostate cancer.

BACKGROUND: Prior randomized studies have shown a survival benefit using combined androgen deprivation therapy (ADT) and radiation therapy for intermediate-risk prostate cancer. However, these studies either used low doses of radiation (66.6 Gy to isocenter) or imaged guidance was not available. This study reports the initial differences for high dose image guided radiation with or without ADT. METHODS: From 2012 to 2014, 56 patients were treated with and 60 patients without 6 months of ADT (N = 116) in our phase III randomized trial for intermediate-risk prostate cancer. The primary endpoints of the current analysis are Expanded Prostate Cancer Index Composite (EPIC) scores, International Prostate Symptom Score (IPSS) scores, and bowel or urinary adverse events (AEs, graded using CTCAE v4) with and without ADT. Treatment consisted of 81 Gy in 45 treatments (tx) or 100 Gy Pd-103 implant followed by 45 Gy in 25 tx with or without ADT. Cone-beam fiducial-based guidance was done. Statistical analysis included Fisher's exact test, chi-square test, and ANCOVA. RESULTS: Median follow-up for both groups was 2.6 years. Acute or chronic urinary and acute or chronic bowel toxicities were similar with or without ADT (acute urinary: 16 vs 25 G0-1, 39 vs 35 G2 and 1 vs 0 G3, p = 0.17; chronic urinary: 40 vs 45 G1 and 16 vs 15 G2 toxicities, p = 0.68; acute bowel: 56 vs 59 G1 and 0 vs 1 G2 toxicities, p = 0.99; chronic bowel: 56 vs 59 G1 and 0 vs 1 G2 toxicities, p = 0.99). One patient had grade 3 urinary AE (1/116 or 0.8%). No patient had grade 3 bowel AE. With the use of ADT, a temporary decline in the EPIC sexual (p = 0.004) and hormonal scores (p = 0.02) were seen for the first 3 to 6 months after the completion of radiation, but the scores recovered by 12 months. Brachytherapy plus external beam radiation was compared to external beam radiation alone; brachytherapy EPIC urinary irritative scores were temporarily lower at 3 months, 76 vs. 84 (p = 0.006), had higher IPSS scores at 3 months, 15 vs 12 (p = 0.01), and had increased acute urinary AEs (p<0.001). No difference in failures were seen with or without ADT or associated with the use of brachytherapy. SIGNIFICANCE: Low toxicity and minimal temporary bother as measured by EPIC and IPSS were seen in both arms. ADT was well-tolerated and associated with temporary changes.

Prostate cancer: the influence of stigma on quality of life and relationship satisfaction for survivors and their partners.

OBJECTIVES: Prostate cancer (PCa) stigma and its relationship to quality of life (QoL) is a relatively new finding. As the experiences of couples facing PCa are shared, the study examined the relationship between of PCa stigma, QoL, and relationship satisfaction of PCa survivors and their spouses. DESIGN: A correlational design with dyadic data was used. SAMPLE: Participants (N = 80 dyads) were PCa survivors and their spouses sampled from an oncology center and PCa support groups. METHODS: Structural equation modeling was used to assess how stigma related to the QoL and relationship satisfaction of participants. FINDINGS: Stigma had a negative association with QoL, but not relationship satisfaction. There were no significant demographic differences in regards to stigma. CONCLUSION: Overall, stigma has a relationship with the experience of couples, but not with every aspect of their experience. Implications for psychosocial providers: Implications for clinicians in regards to addressing PCa stigma with clients and areas for future research are discussed.

The influence of stigma on the quality of life for prostate cancer survivors.

The purpose of the present study was to investigate the influence of stigma on prostate cancer (PCa) survivors' quality of life. Stigma for lung cancer survivors has been the focus of considerable research (Else-Quest & Jackson, 2014); however, gaps remain in understanding the experience of PCa stigma. A cross-sectional correlational study was designed to assess the incidence of PCa stigma and its influence on the quality of life of survivors. Eighty-five PCa survivors were administered survey packets consisting of a stigma measure, a PCa-specific quality of life measure, and a demographic survey during treatment of their disease. A linear regression analysis was conducted with the data received from PCa survivors. Results indicated that PCa stigma has a significant, negative influence on the quality of life for survivors (R2 = 0.33, F(4, 80) = 11.53, p < 0.001). There were no statistically significant differences in PCa stigma based on demographic variables (e.g., race and age). Implications for physical and mental health practitioners and researchers are discussed.

Salvage brachytherapy for recurrent prostate cancer.

PURPOSE: To evaluate the role of salvage prostate brachytherapy for locally recurrent prostate cancer after external beam radiation alone. METHODS AND MATERIALS: Sixty-nine consecutive patients treated with salvage brachytherapy after a local failure were analyzed. All patients were found to have pathologic proven recurrent prostate cancer at least 2 years after initial therapy and no regional or distant disease on imaging studies. Pd-103 was used with a prescribed pD90 of 100 Gy. In total, 89.9% of patients received androgen suppression (AS) as part of their salvage therapy. Patients whose prostate-specific antigen >5.0 ng/mL while on AS were considered to have castration resistant prostate cancer (CRPC). Patients on AS >6 months before salvage brachytherapy were considered to have delayed therapy. Patients retreated within 5 years after their initial treatment were considered to have early failures. RESULTS: Total median followup after salvage therapy was 5.0 years (0.6-13.7). From the date of salvage, 5-year biochemical control for low-risk patients was 85.6%, intermediate-risk patients 74.8%, and high-risk patients 66%. Five-year biochemical control was 73.8% for non-CRPC and 22% for CRPC cases (<0.001). Including and excluding CRPC cases, early treatment after failure vs. delayed treatment was significantly better (p<0.05). Chronic adverse events were seen in few patients, with genitourinary Grade 3 toxicity of 8.7% and no genitourinary Grade 4 or gastrointestinal Grade 3 or higher toxicities. CONCLUSIONS: A subset of failures after definitive radiation is local in nature, and excellent control is possible with salvage brachytherapy.

Genome-wide association study identifies a region on chromosome 11q14.3 associated with late rectal bleeding following radiation therapy for prostate cancer.

BACKGROUND AND PURPOSE: Rectal bleeding can occur following radiotherapy for prostate cancer and negatively impacts quality of life for cancer survivors. Treatment and clinical factors do not fully predict rectal bleeding, and genetic factors may be important. MATERIALS AND METHODS: A genome-wide association study (GWAS) was performed to identify SNPs associated with the development of late rectal bleeding following radiotherapy for prostate cancer. Logistic regression was used to test the association between 614,453 SNPs and rectal bleeding in a discovery cohort (79 cases, 289 controls), and top-ranking SNPs were tested in a replication cohort (108 cases, 673 controls) from four independent sites. RESULTS: rs7120482 and rs17630638, which tag a single locus on chromosome 11q14.3, reached genome-wide significance for association with rectal bleeding (combined p-values 5.4×10(-8) and 6.9×10(-7) respectively). Several other SNPs had p-values trending toward genome-wide significance, and a polygenic risk score including these SNPs shows a strong rank-correlation with rectal bleeding (Sommers' d=5.0×10(-12) in the replication cohort). CONCLUSIONS: This GWAS identified novel genetic markers of rectal bleeding following prostate radiotherapy. These findings could lead to the development of a predictive assay to identify patients at risk for this adverse treatment outcome so that dose or treatment modality could be modified.

A 2-stage genome-wide association study to identify single nucleotide polymorphisms associated with development of erectile dysfunction following radiation therapy for prostate cancer.

PURPOSE: To identify single nucleotide polymorphisms (SNPs) associated with development of erectile dysfunction (ED) among prostate cancer patients treated with radiation therapy. METHODS AND MATERIALS: A 2-stage genome-wide association study was performed. Patients were split randomly into a stage I discovery cohort (132 cases, 103 controls) and a stage II replication cohort (128 cases, 102 controls). The discovery cohort was genotyped using Affymetrix 6.0 genome-wide arrays. The 940 top ranking SNPs selected from the discovery cohort were genotyped in the replication cohort using Illumina iSelect custom SNP arrays. RESULTS: Twelve SNPs identified in the discovery cohort and validated in the replication cohort were associated with development of ED following radiation therapy (Fisher combined P values 2.1×10(-5) to 6.2×10(-4)). Notably, these 12 SNPs lie in or near genes involved in erectile function or other normal cellular functions (adhesion and signaling) rather than DNA damage repair. In a multivariable model including nongenetic risk factors, the odds ratios for these SNPs ranged from 1.6 to 5.6 in the pooled cohort. There was a striking relationship between the cumulative number of SNP risk alleles an individual possessed and ED status (Sommers' D P value=1.7×10(-29)). A 1-allele increase in cumulative SNP score increased the odds for developing ED by a factor of 2.2 (P value=2.1×10(-19)). The cumulative SNP score model had a sensitivity of 84% and specificity of 75% for prediction of developing ED at the radiation therapy planning stage. CONCLUSIONS: This genome-wide association study identified a set of SNPs that are associated with development of ED following radiation therapy. These candidate genetic predictors warrant more definitive validation in an independent cohort.

Long-term outcomes and prognostic factors in patients treated with intraoperatively planned prostate brachytherapy.

PURPOSE: Evaluate outcomes and prognostic factors in men with localized prostate cancer. METHODS AND MATERIALS: A total of 3760 patients have undergone prostate seed implantation at our institution. This review is of our initial 304 consecutive patients treated before January 30, 2001. A total of 124 patients were treated with (125)I implant monotherapy and 180 with (103)Pd implant combined with 45-Gy external beam radiation therapy. RESULTS: The median followup was 10.3 years. A 10-year biochemical control for low risk (LR) was 98% , intermediate risk (IR) 94%, high risk (HR) 78%, and HR with one HR factor 88% (p < 0.001); cause-specific survival was 99%, 98%, and 84% for LR, IR, and HR, respectively (p < 0.001); No significant difference in outcome was seen for LR and IR patients (p > 0.3). On multivariate analysis, only pretreatment PSA, Gleason score, and T-stage were significant for biochemical control. Most biochemical failures occurred within 5 years (93%). CONCLUSIONS: With a minimum followup of 10 years, results are excellent and do not differ for LR or IR prostate cancer patients. HR patients are a very heterogeneous group, and excellent results can still be achieved for HR patients with only one HR feature.