The aim of the present study was to evaluate the efficacy and safety of intensity-modulated radiation therapy (IMRT) for elderly patients with prostate cancer (age ≥75 years) compared with younger patients (<75 years). The numbers of patients enrolled into the elderly and younger groups were 238 and 853, respectively. More than half of the patients in the elderly group were high-risk, and the total risk of the elderly group was higher than that of younger group. The median follow-up periods for the elderly and younger groups were 42 (range, 2-108) and 49 (range, 2-120) months, respectively. All patients were treated with IMRT at a dose of 74-78 Gy with or without androgen-deprivation therapy. The biochemical failure-free rates (BFFRs) at 3-year follow-up for the elderly and younger groups were 93.3 and 95.7%, respectively; there was no significant difference between the 2 groups in regard to the BFFR. The clinical failure-free rates (CFFR) at 3-year follow-up for the elderly and younger groups was 95.8 and 98.5%, respectively; the 2 groups did not differ significantly in regard to the CFFR. The cumulative incidence rates of gastrointestinal toxicity (grade ≥2) and genitourinary toxicity (grade ≥2) at 3-year follow-up were 10.5 and 1.3%, respectively; there was no significant difference between the elderly and younger groups. It was concluded that in prostate cancer patients aged 75 years or older, IMRT has a treatment effect equivalent to that in patients <75 years old; adverse events are also comparable.
Keywords: adverse events; elderly patients; external beam radiation therapy; intensity-modulated radiation therapy; prostate cancer.