Acute Toxicity of Ultrahypofractionation Compared With Moderate Hypofractionation in Prostate Cancer Treatment: A Randomized Trial

Abstract

Purpose: We report on the early toxic effects and quality of life of localized prostate cancer radiation therapy in a randomized trial comparing moderate hypofractionation (MHF) with ultrahypofractionation (UHF).

Methods and materials: We randomized patients with intermediate- to high-risk localized prostate cancer to radiation therapy with MHF (70 Gy in 28 daily fractions) or UHF (36.25 Gy in 5 weekly fractions). We analyzed early toxic effects (using Common Terminology Criteria for Adverse Events and Radiation Therapy Oncology Group/Subjective, Objective, Management, Analytic scales) and patient-reported quality of life (using the Expanded Prostate Inventory Composite questionnaire) when all patients had at least 6 months of follow-up.

Results: We randomized 80 participants. Two patients withdrew from radiation therapy. We ran analysis on results for 78 patients. The 2 arms were balanced in key patient and disease characteristics, except for a statistically worse baseline urinary function in the UHF arm (International Prostate Symptom Score >7: 68% vs 36%, P = .004). There were no statistically significant differences between the 2 arms in grade 3 or grade 2 toxic effects: grade ≥3 MHF 8%, UHF 2% (P = .235); grade ≥2 MHF 36%, UHF 24% (P = .235). There were also no significant differences in percentages of patients with a "minimal important change" of quality of life in the Incontinence (MHF 36%, UHF 33%; P = .746), Irritative/Obstructive (MHF 56%, UHF 74%; P = .074), or Bowel domains (MHF 58%, UHF 52%; P = .508) on the Expanded Prostate Inventory Composite questionnaire.

Conclusions: UHF radiation therapy for prostate cancer is well tolerated, and there were no significant differences in toxic effects and quality of life changes between UHF and MHF up to 6 months after treatment in the current trial.