Moderate hypofractionated helical tomotherapy for prostate cancer in a cohort of older patients: a mono-institutional report of toxicity and clinical outcomes.

ABSTRACT

PURPOSE OR OBJECTIVE: To evaluate toxicity and outcomes of moderately hypofractionated helical tomotherapy for the curative treatment of a cohort of patients aged ≥ 75 years with localized prostate cancer (PC). MATERIALS AND METHODS: From January 2013 to February 2017, 95 patients with median age 77 years (range 75-88) were treated for PC. 39% were low risk, 33% intermediate risk (IR), 28% high risk (HR). Median iPSA was 9.42 ng/ml (1.6-107). Androgen deprivation was prescribed according to NCCN recommendations. All patients received 70 Gy in 28 fractions to the prostate; 61.6 Gy were delivered to the seminal vesicles for IR; whole pelvis irradiation with a total dose of 50.4 Gy was added in the HR group. Toxicity evaluation was based on CTCAE V4.0 criteria, biochemical failure was defined following Phoenix criteria. Quality of Life was assessed with the EPIC-26 index. Overall survival and biochemical failure-free survival were analysed with Kaplan-Meier method. RESULTS: With a median follow-up of 36 months (range 24-73), acute and late toxicity were acceptable. No correlation between toxicity patterns and clinical or dosimetric parameter was registered. EPIC-26 showed a negligible difference in urinary and bowel function post-treatment that did not reach statistical significance. The 2- and 3-years OS were 93% and 87% with cancer specific survival of 97.9% and 96.2%. CONCLUSION: Moderate hypofractionated RT reported excellent outcomes in our cohort of older patients. Shorter schedules may be proposed regardless of chronological age facilitating the treatment compliance in the older population.