Three Cases of Lower Urinary Tract Symptoms After Radiotherapy for Prostate Cancer Successfully Treated with Ryutanshakanto

Abstract

Radiotherapy has become an established treatment option for prostate cancer, with modalities such as intensity-modulated radiation therapy (IMRT), image-guided radiation therapy, brachytherapy, and particle beam radiation therapy offering comparable outcomes to surgery. Although acute lower urinary tract symptoms (LUTS) often improve shortly after the completion of definitive radiotherapy for prostate cancer, late-onset symptoms can recur months to years later, sometimes showing resistance to conventional pharmaceutical interventions. This paper reports three cases in which ryutanshakanto, a traditional herbal medicine, demonstrated effectiveness in treating LUTS resulting from acute and late radiation toxicity following definitive radiotherapy for prostate cancer. Case 1involved a patient who experienced late radiation prostatitis and urethritis with LUTS 1 year and 5 months after brachytherapy. Case 2 presented acute radiation-induced LUTS following IMRT, while Case 3 experienced late-onset LUTS more than 5 years after IMRT. In these cases, conventional Western medications failed to control the symptoms adequately, but ryutanshakanto proved to be an effective alternative.