Assessment of late urinary, bowel and sexual function after dose escalation from 70 to 76 Gy using image-guided radiotherapy in curative treatment of prostate cancer.

Objective: The aim of this study was to evaluate the late urinary, bowel and sexual function among men with localized or locally advanced prostate cancer treated with curative radiotherapy after the introduction of image-guided radiotherapy to 76 Gy using the Swedish BeamCath® technique.

Material and methods: All patients treated with curative radiotherapy during 2003-2006 were invited to participate in this retrospective study. In total, 87% (158/181) participated in the study. The median observation time was 35 months. Comparisons were made between the standard 70 Gy (n = 73) and the 76 Gy (n = 85) treatment groups. Assessments of late urinary, bowel and sexual function were questionnaire based, and included function items in the Expanded Prostate Cancer Index Composite.

Results: Most late urinary and bowel symptoms were reported to occur seldom or never in the majority of men, while late sexual toxicity was reported in a large proportion (66%) of men. Seven men (4%) used diapers. Only 25% (n = 40) reported having an erection firm enough for intercourse. None of the reported urinary or sexual function symptoms differed between the treatment groups. Rectal urgency at least once daily was a more frequent symptom in the 70 Gy group than the 76 Gy group (28% vs 9%, p = 0.006). Painful bowel movements were a more common symptom in the 70 Gy group (11% vs 1%, p = 0.01).

Conclusion: Dose escalation up to 76 Gy using the BeamCath technique was not associated with more late toxicities than the standard 70 Gy dose.