Treatment efficiency, outcome and surgical treatment problems in patients suffering from localized embryonal bladder/prostate rhabdomyosarcoma: a report from the Cooperative Soft Tissue Sarcoma trial CWS-96.

Background: To analyze the clinical course, treatment modalities, complications and outcome of patients suffering from localized embryonal bladder/prostate rhabdomyosarcoma (BPRMS) treated on the CWS-96 trial.

Procedure: There were 85 patients with BPRMS enrolled and 63 patients with embryonal non-metastatic BPRMS were analyzed. Fifty-six patients received neoadjuvant chemotherapy and response was assessed radiographically after 9 weeks. Local therapy with radiation and or surgery was performed based on age, tumor size, and response. Patients were treated with adjuvant chemotherapy following local control.

Results: Patient's age ranged from 0 to 16 years with a median follow up of 5.3 years. Eighty nine percent of the patients had IRS group III disease. The 5-year overall survival (OS) for the whole group was 76.3 ± 5.6% and the 5-year event-free survival (EFS) 69.8 ± 6.2%. Seventeen patients underwent preoperative radiochemotherapy followed by tumor resection (5-year-OS: 87.8 ± 8.1%). Eight patients were treated with solely radiochemotherapy (87.5 ± 11.7%). Twenty-five patients received chemotherapy and tumor resection (OS: 83.6 ± 7.5%). Thirteen patients underwent incomplete tumor resection and were treated with radiochemotherapy postoperatively (OS: 39.9 ± 14.8%, P < 0.05 vs. other groups).

Conclusions: Local therapy is an important factor for prognosis of localized embryonal BPRMS. Inadequate primary or secondary surgery compromises the outcome and should be avoided. Radiotherapy alone, complete surgical tumor resection or combined preoperative radiotherapy with surgical resection lead to similar good local control rates and prognosis.