Rectal adenocarcinoma with rectoprostatic fistula following prostate brachytherapy.

An 80-year-old man with history of prostate cancer successfully treated with brachytherapy was initially thought to have Fournier's gangrene until imaging detected a rectoprostatic fistula. Although this is known to be a rare complication of prostate brachytherapy, in this case the aetiology was a new primary rectal adenocarcinoma. It was not possible to catheterise per urethra owing to the fistula, so he was fitted with suprapubic catheter, and underwent palliative loop colostomy. Brachytherapy carries a low risk of second primary cancers, although two previous cases reported such cancers as radiation induced. This is, to our knowledge, the first case of rectal adenocarcinoma following prostate brachytherapy in the literature.