Giant Cell Tumor of the Tendon Sheath in the Anatomical Snuffbox - Report of an Unusual Location.

The aim of this study is to present a case of giant cell tumor of the tendon sheath in the anatomical snuffbox, an extremely unusual location of such neoplasms. A 54-year-old male came to our hospital with a mass in his left hand that had appeared over the past two years, demonstrating a recent rapid increase in size. The physical examination revealed that the mass did not cause any pain or restriction in the range of motion. The neurovascular function remained intact. The magnetic resonance imaging (MRI) detected a 2.5 x 1.5 cm mass in the anatomical snuffbox but without a clear diagnosis. A meticulous marginal surgical excision was performed and biopsy sample was sent for histopathologic examination. Intraoperatively, it was observed that the tumor extended in-between the tendons of the first and third dorsal compartments, reaching the radial artery at the depth of the anatomical snuffbox. Macroscopically, the tumor resembled a giant cell tumor, which was confirmed by histological examination. The patient was discharged from the hospital on the same day. He fully resumed his daily activities three weeks after surgery. Three years later, he remained free of symptoms without any recurrence of the tumor. Giant cell tumor of the tendon sheath is a benign neoplasm that demonstrates local aggressiveness. In several cases, nerves and blood vessels might be entrapped within the tumor. This complication along with its high recurrence rate renders surgical excision of the tumor a particularly demanding procedure.