Granular cell tumor of the common bile duct: a case report.

Granular cell tumors (GCTs) are uncommon soft tissue tumors, usually presenting in the skin and subcutaneous tissue tongue and oral cavity. We present a case report of granular cell tumor of the common bile duct involving both extra- and intrapancreatic portions. The histogenesis appears to be related to Schwann cells, similar to granular cell tumors of other sites, as evidenced by histologic and immunohistochemical findings. Review of the English literature concerning biliary tract GCTs revealed a high occurrence in African-American females in their third decade. By-pass operation to correct the biliary tract obstruction may be appropriate, if the nature of the tumor can be obtained from intraoperative diagnosis by frozen section.