Congenital rhabdomyosarcoma: A report from the European paediatric Soft tissue sarcoma Study Group.

Procedure: Congenital rhabdomyosarcoma (RMS) represents a challenging disease due to its characteristics and the difficulties in delivering treatment in this immature population.

Methods: We analyzed treatment and outcome of patients with congenital RMS, defined as tumor diagnosed in the first 2 months of life, enrolled in the European paediatric Soft tissue sarcoma Study Group protocols.

Results: Twenty-four patients with congenital RMS were registered. All, except one patient (PAX3-FOXO1-positive metastatic RMS), had favorable histology and localized disease. Three patients had VGLL2-CITED2/NCOA2 fusion. Complete tumor resection was achieved in 10 patients. No radiotherapy was given. Chemotherapy doses were adjusted to age and weight. Only two patients required further dose reduction for toxicity. The 5-year event-free survival (EFS) and overall survival (OS) were 75.0% (95% confidence interval [CI] 52.6-87.9) and 87.3% (95% CI 65.6-95.7), respectively. Progressive disease was the main cause of treatment failure.

Conclusion: Patients with congenital RMS presented with a favorable disease, allowing weight- and age-adjusted doses of chemotherapy and avoidance of irradiation, without compromising the outcome.