Many patients experience bowel and bladder toxicity during the acute phase of radiotherapy for prostate cancer. Recent literature indicates that hypofractionation (HF) might increase this acute response but little is known on patient-reported outcome during this phase with HF. We evaluated the course of patient-reported acute symptoms during HF vs standard fractionated (SF) radiotherapy within the hypofractionated irradiation for prostate cancer (XXXX) trial.
In the XXXX trial patients were treated with either 64.4 Gy (HF) in 19 fractions (3x per week) or 78 Gy (SF) in 39 fractions (5x per week). NTD2Gy for acute toxicity (α/β ratio=10) for HF was 72.1 Gy with a similar dose rate of 10.2 Gy/week. Among the 794 patients who were previously eligible for acute Grade ≥2 toxicity assessment, N=717 had filled out ≥1 symptom questionnaires. For each maximum symptom we scored "any complaint" and "moderate-severe complaint". Differences were tested by Chi-square test and associations with clinical factors were tested using logistic regression. Significance was set at p≤0.008 to adjust for multiple testing.
We observed significantly higher rates of moderate-severe painful defecation (HF 10.8%, SF 5.3%), any mucus discharge (HF 47.1%, SF 37.4%), any rectal blood loss (HF 16.1%, SF 9.3%), increased daily stool frequency ≥4 and ≥6 (HF 34.6%/13.8%, SF25.6%/7.0%), and any urinary straining (HF 69.9%, SF 58.0%). At 3 months post-radiotherapy, rates dropped considerably with similar levels for HF and SF. Hormonal treatment was associated with les acute GI symptoms.
The increased patient-reported acute rectal symptoms with HF confirmed the previously reported results on acute grade >=2 rectal toxicity. The increased bladder symptoms with HF was not identified previously. These observations contradict the NTD2Gy calculations. We observed no patterns of persisting complaints with HF after the acute period, therefore HF is well tolerated and only associated with a temporary increase of symptoms.
International journal of radiation oncology, biology, physics. 2021 Nov 02 [Epub ahead of print]
F Sinzabakira, W D Heemsbergen, F Pos, L Incrocci
Department of Radiotherapy, Erasmus MC Cancer Institute, Rotterdam, The Netherlands; Rwanda Cancer Centre, Rwanda Military Hospital, Kigali, Rwanda., Department of Radiotherapy, Erasmus MC Cancer Institute, Rotterdam, The Netherlands. Electronic address: ., Department of Radiation Oncology, Netherlands Cancer Institute, Amsterdam, The Netherlands., Department of Radiotherapy, Erasmus MC Cancer Institute, Rotterdam, The Netherlands.