Hepatic angiomyolipoma growing to cause epigastric discomfort: a case report.

We report herein a case of hepatic angiomyolipoma growing to cause epigastric discomfort. A 33-year-old man was referred for excisional operation of hepatic hypervascular tumor, complaining of epigastric discomfort. The tumor had enlarged from the time 3 years before when the tumor was diagnosed as hepatic hemangioma in the lateral segment. Partial hepatectomy with tumor resection was carried out. Pathological diagnosis was confirmed as hepatic angiomyolipoma with a finding of enriched vessels, extramedullary hematopoiesis, fatty tissue, and most epithelioid cells immunoreactive to HMB-45. Further analysis also revealed positive staining cells for granulocyte colony-stimulating factor. It was suggested that growth of hepatic angiomyolipoma in this case might be caused by extramedullary hematopoiesis induced by granulocyte colony-stimulating factor.