Pediatric aggressive fibromatosis of the head and neck: a 20-year retrospective review.

UNLABELLED: Aggressive fibromatosis in children is a rare, benign condition that is locally infiltrative and destructive. It often presents as a rapidly growing, painless lump in the head and neck region. To date, only small series and case reports have been reported, and the management of the condition remains unclear. Recently, nuclear beta-catenin expression has been suggested as a tumor-specific marker for aggressive fibromatosis (desmoid).

AIM: The aims of the study were to review our experience of the presentation, management, and treatment outcome of pediatric aggressive fibromatosis in the head and neck and to identify the presence of the desmoid tumor marker beta-catenin within this population.

METHOD: The study was conducted as a retrospective case review of children diagnosed with aggressive fibromatosis in the head and neck for a period of 20 years and a review of the literature. Pathologic review of the original tumor specimens was undertaken for evidence of positive tumor margins and presence of nuclear beta-catenin expression.

RESULTS: A total of 10 patients (6 males, 4 females) were identified. The age at presentation ranged from 12 months to 14 years. In total, 8 patients were treated with surgery alone. This included 7 patients with extension of the tumor to the resection margin; all had good long-term outcomes with no disease progression. Two patients received chemoradiotherapy, one as primary treatment, and the other as adjuvant treatment after gross incomplete resection. Both resulted in poor outcomes requiring further treatments. Within our series of pediatric fibromatosis, only 4 cases (40%) had positive results for any nuclear beta-catenin expression, and 6 (60%) of 10 patients had negative results for beta-catenin.

CONCLUSION: Our experience is that total gross resection and preservation of form and function is of higher priority than achieving a negative resection margin. Pediatric fibromatosis though aggressive is still a benign condition, and careful thought should be taken before considering adjuvant chemoradiotherapy. Nuclear beta-catenin expression should not be considered a specific tumor marker for pediatric aggressive fibromatosis of the head and neck. Pediatric aggressive fibromatosis in this region may be a distinct subtype of desmoid tumor from its adult form.