Ten-Year Update of a Randomized, Prospective Trial of Conventional Fractionated Versus Moderate Hypofractionated Radiation Therapy for Localized Prostate Cancer.

PURPOSE: The previously published single institution randomized prospective trial failed to show superiority in the 5-year biochemical and/or clinical disease failure (BCDF) rate with moderate hypofractionated intensity-modulated radiation therapy (H-IMRT) versus conventionally fractionated IMRT (C-IMRT). We now present 10-year disease outcomes using updated risk groups and definitions of biochemical failure. METHODS: Men with protocol-defined intermediate- and high-risk prostate adenocarcinoma were randomly assigned to receive C-IMRT (76 Gy in 38 fractions) or H-IMRT (70.2 Gy in 26 fractions). Men with high-risk disease were all prescribed 24 months of androgen deprivation therapy (ADT) and had lymph node irradiation. Men with intermediate risk were prescribed 4 months of ADT at the discretion of the treating physician. The primary endpoint was cumulative incidence of BCDF. We compared disease outcomes and overall mortality by treatment arm, with sensitivity analyses for National Comprehensive Cancer Network (NCCN) risk group adjustment. RESULTS: Overall, 303 assessable men were randomly assigned to C-IMRT or H-IMRT. The median follow-up was 122.9 months. Per updated NCCN risk classification, there were 28 patients (9.2%) with low-risk, 189 (62.4%) with intermediate-risk, and 86 (28.4%) with high-risk prostate cancer. The arms were equally balanced for clinicopathologic factors, except that there were more black patients in the C-IMRT arm (17.8% v 7.3%; P = .02). There was no difference in ADT use (P = .56). The 10-year cumulative incidence of BCDF was 25.9% in the C-IMRT arm and was 30.6% in the H-IMRT arm (hazard ratio, 1.31; 95% CI, 0.82 to 2.11). The two arms also had similar cumulative 10-year rates of biochemical failure, prostate cancer-specific mortality, and overall mortality; however, the 10-year cumulative incidence of distant metastases was higher in the H-IMRT arm (rate difference, 7.8%; 95% CI, 0.7% to 15.1%). CONCLUSION: H-IMRT failed to demonstrate superiority compared with C-IMRT in long-term disease outcomes.

Effects of interruptions of external beam radiation therapy on outcomes in patients with prostate cancer.

INTRODUCTION: To evaluate if interruptions of external beam radiation therapy impact outcomes in men with localized prostate cancer (PCa). METHODS: We included men with localized PCa treated with three-dimensional conformal radiotherapy (3D-CRT) or intensity-modulated radiation therapy (IMRT) of escalated dose (≥74 Gy in 1.8 or 2 Gy fractions) between 1992 and 2013 at an NCI-designated cancer centre. Men receiving androgen deprivation therapy were excluded. The non-treatment day ratio (NTDR) was defined as the number of non-treatment days divided by the total elapsed days of therapy. NTDR was analysed for each National Comprehensive Cancer Network (NCCN) risk group. RESULTS: There were 1728 men included (839 low-risk, 776 intermediate-risk and 113 high-risk), with a median follow up of 53.5 months (range 12-185.8). The median NTDR was 31% (range 23-71%), translating to approximately 2 breaks (each break represents a missed treatment that will be made up) for 8 weeks of RT with 5 treatments per week. The 75 percentile of NTDR was 33%, translating to approximately 4 breaks, which was used as the cutoff for analysis. There were no significant differences in freedom from biochemical failure, freedom from distant metastasis, cancer specific survival, or overall survival for men with NTDR ≥33% compared to NTDR<33% for each risk group. Multivariable analyses including NTDR, age, race, Gleason score, T stage, and PSA were performed using the proportional hazards regression procedure. NTDR≥33% was not significantly associated with increased hazard ratio for outcomes in each risk group compared to NTDR<33%. CONCLUSION: Unintentional treatment breaks during dose escalated external beam radiation therapy for PCa did not cause a significant difference in outcomes, although duration of follow up limits the strength of this conclusion.

Men's health supplement use and outcomes in men receiving definitive intensity-modulated radiation therapy for localized prostate cancer.

BACKGROUND: Approximately 50% of newly diagnosed cancer patients start taking dietary supplements. Men's health supplements (MHSs), which we define as supplements that are specifically marketed with the terms men's health and prostate health (or similar permutations), are often mislabeled as having potential anticancer benefits. OBJECTIVE: We evaluated the effects of MHSs on patient outcomes and toxicities in patients who were undergoing definitive intensity-modulated radiation therapy (IMRT) for localized prostate cancer. DESIGN: This retrospective analysis included patients who were being treated at a National Cancer Institute-designated comprehensive cancer center and consented to have information stored in a prospective database. MHSs were queried online. Outcome measures were freedom from biochemical failure (FFBF) (biochemical failure was defined with the use of the prostate-specific antigen nadir + 2-ng/mL definition), freedom from distant metastasis (FFDM), cancer-specific survival (CSS), and overall survival (OS) as well as toxicities. Kaplan-Meier analysis, log-rank tests, Fine and Gray competing-risk regression (to adjust for patient and lifestyle factors), and Cox models were used. RESULTS: From 2001 to 2012, 2207 patients were treated with IMRT with a median dose of 78 Gy, and a median follow-up of 46 mo. Of these patients, 43% were low risk, 37% were intermediate risk, and 20% were high risk; 10% used MHSs. MHSs contained a median of 3 identifiable ingredients (range: 0-78 ingredients). Patients who were taking an MHS compared with those who were not had improved 5-y OS (97% compared with 92%, respectively; P = 0.01), but there were no differences in the FFBF (94% compared with 89%, respectively; P = 0.12), FFDM (96% compared with 97%, respectively; P = 0.32), or CSS (100% compared with 99%, respectively; P = 0.22). The unadjusted association between MHS use and improved OS was attenuated after adjustment for patient lifestyle factors and comorbidities. There was no difference in toxicities between the 2 groups (late-grade 3-4 genitourinary <3%; gastrointestinal <4%). CONCLUSION: The use of MHSs is not associated with outcomes or toxicities.

Effects of Time to Treatment on Biochemical and Clinical Outcomes for Patients With Prostate Cancer Treated With Definitive Radiation.

INTRODUCTION: The purpose of this study was to evaluate if time to treatment (TTT) has an effect on outcomes for patients with localized prostate cancer treated with definitive external beam radiation therapy (EBRT). PATIENTS AND METHODS: We included 4064 patients (1549 low-risk, 1612 intermediate-risk, and 903 high-risk) treated with EBRT. For each National Comprehensive Cancer Network (NCCN) risk group, TTT (defined as the time between initial positive prostate biopsy and start of RT) was analyzed in 4 intervals: < 3, 3-6, 6-9, and 9-24 months. We recorded the use of androgen deprivation therapy among patients with intermediate-risk and high-risk disease. RESULTS: The median TTT was 3.3 months (range, 0.6-23.5 months), and it was similar for each risk group (range, 3.3-3.4 months). The median follow up was 64 months. There were no significant differences in biochemical failure, distant metastasis, or overall survival for patients with TTT < 3, 3-6, 6-9, or 9-24 months for each risk group. There were also no significant differences in the outcomes at 5 years when patients with TTT > 3.3 months were compared with those with TTT ≤ 3.3 months for each risk group. For high-risk men, 328 of 450 (72.9%) with TTT > 3.3 months were on androgen deprivation therapy (ADT) versus 299 of 453 (66%) with TTT ≤ 3.3 months. Among men with high-risk cancer treated without ADT, there remained no significant difference in outcomes between TTT > 3.3 months and TTT ≤ 3.3 months. CONCLUSION: TTT was not associated with significant differences in outcomes among each risk group of men with localized prostate cancer treated with EBRT. Among the high-risk patients, there were no observed detriments in outcomes with TTT > 3.3 months regardless of androgen deprivation therapy use.