Session Item

To present prospectively collected acute toxicity data and patient reported outcome measures (PROMs) in patients treated for prostate cancer (PCa) with ultrahypofractionated proton beam therapy (PBT).

48 men with histologically proven prostate cancer received PBT between January 2019 and January 2021 at our centre.  Of these, 9 men were excluded as they did not return follow-up PROMS questionnaires; 39 patients were included in this analysis.  Clinical toxicity data was captured and analysed using both Radiotherapy Toxicity Oncology Group (RTOG) and the Expanded Prostate Cancer Index Composite (EPIC) grading and questionnaires.

In the acute period (< 90 days from treatment completion), no patients exhibited >grade 2 genitourinary and/or gastrointestinal toxicities.  RTOG data show the commonest acute genitourinary toxicities were urinary frequency (25/39 patients, 64%) and dysuria (8/39 patients, 21%) and the most common acute gastrointestinal toxicities were diarrhoea (4/39 patients, 10%) and flatulence (3/39 patients, 8%).  The EPIC questionnaire PROMs were consistent the oncologist RTOG toxicity gradings.

Both RTOG and PROMs data show that ultrahypofractionated proton beam therapy for PCa  results in acceptable levels of acute genitourinary and gastrointestinal toxicities.