Background and objectives: Giant cell tumor of the tendon sheath (GCTTS) is a lesion of uncertain etiology. To better interpret pathogenesis and aid in the differentiation of GCTTS from other similar pathological processes we reviewed the literature and analyzed the available information.
Methods: We retrospectively studied clinicopathologic findings in 28 cases of GCTTS on the basis of anatomic location and histologic appearance of the lesion.
Results: The GCTTS could be divided into those involving the common digits (20 cases) and larger joint group (8 cases) based on anatomic location. Grossly the digit tumors were small, multiple, surrounded by a thin fibrous capsule, and had a variegated appearance, while the large joint tumors were relatively large and covered by one or more layers of synovium. Microscopically both groups consisted of a mixture of round to polygonal histiocytes, foam cells, hemosiderin laden macrophages, and multinucleated giant cells. The giant cells seemed more abundant in the digit tumors, while the pseudoglandular spaces lined by synovial cells were more striking in the large joint group.
Conclusions: Local excision was the treatment of choice in the majority of the patients. Eight patients had local recurrence.