RESUMO
Mesenteric aggressive fibromatosis, also known as abdominal desmoid tumor (DT), is a rare monoclonal neoplasm arising from muscoloaponeurotic structures, caused by a generalized defect in growth regulation of the connective tissue. Childhood abdominal DT is very rare (1), and the mesenteric localization is one of the rarest forms (approximately 5% of total cases). Despite its benign microscopic appearance and nonmetastasizing behavior, abdominal DT shows a high risk of recurrence (30%-80%) (2) and local aggressive growth. We report a case of a 7-year-old girl with a giant mesenteric fibromatosis, with multiple recurrence after surgical resections, successfully treated with low-dose of vinblastine (3-6 mg/m(2) per week) and methotrexate (20-30 mg/m(2) per week) for 24 months (every 7 days for 11 months and every 2 weeks for the last 13 months). After a follow-up of 47 months from the end of treatment, the child is in good health and in complete remission. Prolonged therapy with low-dose methotrexate and vinblastine appears to control abdominal DT and is associated with stable disease in patients with tumor unresponsive to surgery.