EC Gastroenterology and Digestive System

Background: Tenosynovial giant cell tumor (TSGCT) is a rare, benign tumour arising from joint synovia, bursae, and tendon sheaths. The majority of cases are localized, presenting with a localized lesion of the synovium, with only 10% of presentations being of a diffuse type synovial involvement.

Case Report: We present our case of 41 years old female that presented with right knee symptoms, namely instability, and locking associated with a right thigh mass of 4 months duration. Examination of the right distal thigh showed a large mass. The mass was firm and irregular, mobile with mild tenderness on deep palpation. Post-subtotal surgical resection diagnosed diffuse TSGCT of the right knee that required adjunct synoviothesis. At the last follow-up, she had improved pain, and range of movement with mild residual swelling and she was still awaiting adjunct synovial ablation.

Conclusion: TSGCT is a rare benign heterogeneous tumour. The pathological type at presentation guides the viable surgical treatment option. The localized type is usually addressed with arthroscopic synovectomy while the diffuse types requires combined approaches similar to our case of discussion. Biologics and novel therapies may hold potential for future cases.

 Keywords: Case Report; Tenosynovial Giant Cell Tumor; Knee; Tumor; Classification

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