Treatment of angiomatoid fibrous histiocytoma after unplanned excision: a case report

BACKGROUND: Angiomatoid fibrous histiocytoma (AFH) is a relatively uncommon soft tissue tumor of intermediate biologic potential. It occurs in subcutaneous regions of the extremities or the trunk, usually presenting in children or young adults. This is the first reported case of subcutaneous AFH that developed in the iliac region and was treated with an unplanned resection. CASE PRESENTATION: An 11-year-old girl noticed a small subcutaneous nodule in the iliac region. As the nodule was asymptomatic, it was observed naturally for a year, after which her parents consulted her doctor due to gradual growth of the nodule. The tumor was resected marginally without biopsy by a non-specialized surgeon. Based on the histology of the resected specimen, the tumor was suspected to be a sarcoma. The patient was referred to our hospital where we reinvestigated the histology of the tumor using immunohistochemistry. After confirming diagnosis of the tumor as an AFH, we undertook additional extensive resection in the iliac region where the tumor had developed. There was no evidence of tumor residue in the resected specimen. It has been 3 years since the operation, and there has been no evidence of recurrence. CONCLUSION: We treated a case of AFH after unplanned resection. If subcutaneous tumors in the iliac region are detected, a diagnosis of AFH should be considered and a simple resection avoided.