Inflammatory pseudotumors in children.

Inflammatory pseudotumors are so named because they mimic malignant tumors clinically and radiologically. Most often seen in the lungs of young adults, they consist of localized proliferations of mononuclear inflammatory cells and myofibroblasts. There are scattered reports of these tumors occurring in various sites in children. We report five cases of these rare lesions in children; four arising intraabdominally and one in the lung. In contrast to the usual presentation in adulthood, these children were all previously healthy. One child, with the tumor arising from the urinary bladder, was originally diagnosed as having a malignant sarcoma and underwent pelvic exenteration and chemotherapy for this subsequently-proven benign lesion. Local recurrence occurred in one case. Total excision is indicated and is usually possible without unacceptable morbidity. Our cases and a review of the literature point out the importance of pathologic differentiation of these lesions from malignancy with early appropriate surgery.