Acute Side-effects of Different Radiotherapy Treatment Schedules in Early Prostate Cancer

Abstract

Background: Optimal radiation therapy (RT) fractionation in early prostate cancer in elderly patients is controversial. We compared acute toxicities of fractionation schedules: 78/2 Gy, 60/3 Gy and 36.25/7.25 Gy, in this single-centre study. We also evaluated the effect of the rectal immobilization system Rectafix on quality of life (QoL).

Patients and methods: Seventy-three patients with one or two intermediate prostate cancer risk factors according to National Comprehensive Cancer Network criteria were recruited. Twenty-one patients were treated with 78/2 Gy and 60/3 Gy, and 31 patients with 36.25/7.25 Gy. Their QoL data were assessed with regard to genitourinary, gastrointestinal and sexual wellbeing at the beginning and end of RT and at 3 months after treatment. Rectafix was used in the 78/2 Gy and 60/3 Gy groups.

Results: There were no statistically significant QoL differences in between the treatment groups 3 months after RT. The 78/2 Gy group had significantly increased bowel movements between baseline and 3 months after RT (p=0.036). At 3 months after RT, this group also had significantly more erectile dysfunction than the 60/3 Gy group (p=0.025). At the end of RT, the 78/2 Gy group had more symptoms than the 36.25/7.25 Gy group. Rectafix did not reduce acute toxicities in the 78/2 Gy or 60/3 Gy groups.

Conclusion: Treatment with the 78/2 Gy schedule is no longer to be recommended due to its increased acute toxicity compared to treatments of 60/3 Gy and 36.25/7.25 Gy. The shortest schedule of 36.25 Gy in five fractions seems to be a convenient treatment option with tolerable acute toxicity.

Keywords: Prostate cancer radiotherapy; acute side-effects; quality of life; rectal displacement device; stereotactic body radiotherapy.