Metastatic rhabdomyosarcoma: a retrospective review of patients treated at the hospital for sick children between 1989 and 1999.

Children with metastatic rhabdomyosarcoma (RMS) continue to fare poorly (3-year survival 20-30%). Various therapies, including end-intensification with high-dose chemotherapy and stem cell support, have been used in an attempt to improve the outcome of these patients. The authors reviewed their clinical experience over a 10-year period to identify predictors of outcome in these patients. The authors reviewed the clinical characteristics, treatment, and outcome of all patients with metastatic RMS diagnosed and treated at the Hospital for Sick Children between 1989 and 1999. Kaplan-Meier curves were generated to compare survival and failure-free survival of different subgroups of patients. Differences between groups were analyzed using univariate analysis and the log-rank test. Seventeen patients with metastatic RMS were identified. Thirteen patients were treated with standard chemotherapy +/- radiotherapy and four received high-dose end-intensification therapy with stem cell support. The estimated 3-year overall survival (OS) and failure-free survival rates for all patients were 35% (95% CI 13-58) and 29% (95% CI 18-40), respectively. Patients with embryonal histology, metastases confined to the lung, and age younger than 10 years had a 3-year OS of 100%, compared with an OS of 0% for the remaining patients (P < 0.0006). The median follow-up for the five survivors was 5.5 years. The authors have identified a subset of children with metastatic RMS having embryonal histology, age less than 10 years, and only pulmonary metastases who have favorable survival outcomes when treated with chemotherapy with or without stem cell support.