Abdominal Inflammatory Myofibroblastic Tumor in Children

ABSTRACT

Inflammatory myofibroblastic tumor (IMT) is a rare reactive lesion characterized by the feature of myofibroblasts and a mixed inflammatory infiltrate that rarely undergoes malignant transformation. Extrapulmonary IMTs in children have been described involving the mesentery, omentum, retroperitoneum, abdominal soft tissues, liver, bladder, mediastinum, head and neck, extremity, appendix, and kidney. Medical records of children treated with abdominal IMT between 1985 and 2005 were reviewed retrospectively. Seven children were treated for IMT with the mean age of 3y 2m (range, 1y 1m to 14y). Tumors were located in transverse mesocolon (n=2), omentum (n=1), porta hepatis (n=2), complex site (antrum, duodenum, common bile duct, porta hepatis) (n=2). The symptoms included abdominal mass, fever, jaundice, abdominal pain and anemia. The masses were excised totally in transverse mesocolon, omentum IMT and there is no evidence of recurrence (follow-up periods 6y 8m, 8y 9m, 4y 10m). In porta hepatis IMT, liver transplantations were performed and there is no evidence of recurrence (follow period 6y 8m, 8y 7m). In one case of complex site IMT, partial excision of mass was performed and he still survived with no change of the residual tumor during follow-up period. The other one of complex site IMT denied further treatment after the biopsy. In conclusion, complete surgical excision including liver transplantation and close follow-up are mandatory for the abdominal IMT in child.