A Rare Case of Tenosynovial Giant Cell Tumor in Palmar Aspect of Ring Finger of Left Hand

Introduction: Giant cell tumor of the tendon sheath (GCTTS) is an uncommon benign soft tissue tumor of unknown etiology. It is seen more commonly in hand than ankle and foot. It presents as a painless and palpable swelling. Its diagnosis is mostly established by histopathology after surgical resection, although pre-operative imaging and fine-needle aspiration cytology (FNAC) support its suspicion. Herein, a case of GCT of flexor tendon sheath of the right ring finger is reported due to its rarity. Case Report: A 30-year-old female presented with complaints of swelling over the front of the right ring finger for 6months.. The swelling was spontaneous, painless, and very slowly progressive. Examination revealed a 2 cm * 1.5 cm firm swelling situated on the palmar aspect of the right ring finger over proximal inter phalangeal joint. Swelling was well defined, having smooth surface, uniformly firm consistency and could be moved sideways easily. X-ray of the hand showed localized soft tissue shadow in the involved area without any bony involvement. Ultrasonography of the finger showed soft tissue mass.MRI revealed Moderate to intense heterogeneous enhancement suggesting giant cell tumor.. Excisional biopsy was done. Histopathology showed typical features of GCTTS. Conclusion: GCTTS should be kept as a differential diagnosis in soft tissue tumors of hand in adults. FNAC followed by excisional biopsy is diagnostic and curative, but the patient should be followed up for detecting and managing recurrences.