Role of adjuvant chemotherapy in the treatment of surgically resected pediatric nonrhabdomyosarcomatous soft tissue sarcomas: A Pediatric Oncology Group Study.

Purpose: To prospectively study the value of adjuvant chemotherapy in pediatric patients with surgically resected nonrhabdomyosarcomatous soft tissue sarcomas (NRSTS).

Patients And Methods: From June 1986 to May 1992, after complete surgical resection (+/-radiotherapy) of their NRSTS, 81 eligible patients either received adjuvant chemotherapy comprising vincristine, dactinomycin, cyclophosphamide, and doxorubicin or were observed. Only 30 patients accepted randomization, and 15 were assigned to each regimen. Of the remaining 51 patients, 19 elected adjuvant chemotherapy and 32 elected observation.

Results: Patients were predominantly male, and 69% of all patients were white. The median age at diagnosis was 12.3 years (range, 9.2 to 20.7 years). For the 81 eligible patients, the 5-year overall survival estimate was 84.5% +/- 4.4% and event-free survival was 72.2% +/- 5.4%. Among randomized patients, the 5-year estimated overall survival rate was 93.3% +/- 7%, and the event-free survival rate was 86.7% +/- 9.5% for the observation group, compared with 69.2% +/- 13% and 40.7% +/- 14%, respectively, for those who received chemotherapy. The significantly worse outcome of patients who received adjuvant chemotherapy disappeared when survival was stratified by tumor grade. Among all patients, a grade 3 lesion conferred a significant disadvantage with respect to event-free survival (P =.0001).

Conclusion: The administration of adjuvant chemotherapy according to the schedule and dosages used in our trial did not improve the outcome of children with resected NRSTS. In this study, tumor grade was the most important predictor of clinical outcome in patients with resected NRSTS, and this factor should be incorporated into the stratification of patients in future trials.