Improvements in the Treatment of Patients Suffering from Bladder-Prostate Rhabdomyosarcoma: A Report from the CWS-2002P Trial

Modern treatment concepts for bladder/prostate rhabdomyosarcoma (BPRMS) are designed to improve survival, to reduce therapy intensity, and to increase bladder preservation rates. Nevertheless, treatment is not optimal. The purpose of this study was to analyze BPRMS patients treated within the CWS-2002P trial regarding outcome, treatment modalities, complications, and to compare the data with the precursor trial CWS-96.Fifty children with localized embryonal BPRMS were analyzed. Eight patients were excluded. Patients received neoadjuvant chemotherapy. At week 9, reassessment using MRI scan was performed. Depending on tumor size, age, and response, local therapy consisting of radiotherapy and/or surgery was initiated. After local therapy, systemic therapy was continued.Patients' median age was 35.6 months. Median follow-up was 59 months. The 5-year OS was 84.5 % and the 5-year ES 79.9 %. Ten patients underwent combined radiochemotherapy and tumor resection (5-year ES: 87.5 %). Six patients were treated solely with radiochemotherapy (5-year ES: 60 %). Twenty-six patients received preoperative chemotherapy followed by tumor resection (ES: 80.8). One patient was treated with chemotherapy only and survived. The bladder preservation rate was 80.9 %.The outcome within the CWS-2002P trial regarding OS and ES seemed to be better than in the precursor trial CWS-96 due to a reduction of protocol violations, but there was no statistical significant difference possibly due to low numbers. Radiotherapy was used less frequently, and the bladder preservation rate was slightly higher. Novel concepts will be required in the future to improve bladder preservation rates.