Changes in Bladder Volume During Radiotherapy for Prostate Cancer.

BACKGROUND/AIM: Patients irradiated for prostate cancer may experience urinary toxicity, particularly if the bladder volume is small. A mobile application (app) that reminds the patients to drink water prior to each radiation fraction may help avoid small volumes. This study investigating bladder volumes during a radiotherapy course is a prerequisite for a prospective trial testing such a reminder app. PATIENTS AND METHODS: Frequency of bladder volumes <200 ml and seven potential risk factors were retrospectively evaluated in 72 patients receiving external beam radiotherapy for non-metastatic prostate cancer. RESULTS: The mean and median values of the numbers of radiation fractions with bladder volumes <200 ml were 17.8 (standard deviation=12.0) and 16.5 (interquartile range Q1-Q3=7.5-29.5) fractions, respectively. Higher numbers of fractions with volumes <200 ml were significantly associated with pre-radiotherapy bladder volumes <200 ml (p<0.001) and high-risk prostate cancer (p=0.014). CONCLUSION: The proportion of bladder volumes <200 ml during the radiotherapy course was high and needs to be decreased. Pre-radiotherapy bladder volume and risk level of prostate cancer were significant risk factors for higher numbers of fractions with volumes <200 ml. These results are important for designing a prospective trial.

Seasonal Impact on Grade ≥2 Dermatitis in Patients With Breast Cancer Undergoing Radiotherapy: A Supplementary Analysis.

BACKGROUND/AIM: We investigated grade ≥2 dermatitis in patients irradiated for breast cancer. This study evaluated associations between dermatitis and the season during which radiotherapy took place. PATIENTS AND METHODS: Associations between the season and grade ≥2 dermatitis were retrospectively evaluated in 327 breast cancer patients. Seasons were March to May (spring), June to August (summer), September to November (autumn), and December to February (winter). Subgroup analyses were performed considering fractionation, radiation technique, treatment volume, radiation boost, and deep-inspiration breath-hold technique. Furthermore, warmer and cooler months were compared. RESULTS: The season had no significant impact on the rate of grade ≥2 dermatitis in the entire cohort (p=0.63) nor in the subgroup analyses (p-values between 0.17 and 0.82). No significant difference in rate was found between warm and cool months. CONCLUSION: Grade ≥2 dermatitis was not associated with the season during which radiotherapy was performed. This factor may not be important for stratification in prospective trials.