Pediatric desmoid tumor: retrospective analysis of 63 cases.

PURPOSE: This study was conducted to evaluate clinical prognostic factors predictive of the probability of recurrence of desmoid tumor (DT).

PATIENTS AND METHODS: Sixty-three patients with histologically confirmed diagnosis of DT were retrospectively studied. Median age at diagnosis was 13 years. Patient distribution by site was as follows: 61% extremities, 18% head and neck, 13% trunk (including 5% intraabdominal), and 8% multicentric lesions. All patients had partial or complete resections; 20 patients also received radiotherapy and/or chemotherapy.

RESULTS: At a median follow-up time of 6 years since first treatment, the overall actuarial probability of having one or more recurrences was 75%. Age, sex, site, size, or number of previous recurrences had no significant impact on the likelihood of recurrence. The only factor associated with an increased proportion of recurrence-free patients was a negative margin of resection (70% v 15% with positive margins; P = .006). Of the four patients with more than 3 years follow-up since chemotherapy, two recurred, and of the 11 patients with the same follow-up after radiotherapy, four recurred, including two of five patients who received a dose of 50 Gy or more. No deaths directly related to tumor invasion were observed.

CONCLUSION: A surgical approach aiming at clear margins is presently the best treatment option. When this cannot be accomplished without severe disfigurement or function impairment, partial resection is an acceptable alternative, but one associated with a high risk of regrowth. Whether adjuvant strategies should be used in this situation remains to be addressed.