Synovioma of the Hand: Report of a Case

Tumors of the synovial tissues of joints, tendon sheaths and bursae are uncommon, and published reports of such tumors are few. Several authors, however, as Lejars and Rubens-Duval (1), Smith (2), and King (3), have noted distinctive features in these tumors, connected apparently with the nature of the tissue of origin. The names given tumors of this type by various writers (1), such as “endothelioma synoviale,” and “synovial sarco-endothelioma,” reflect a belief, no longer held by anatomists (Maximow, 4), that synovial membrane is endothelial in nature, and serve to place these tumors in a very uncertain category. The term “synovioma” has been applied by Smith (2) and is used by others (King, 3; Knox, 5), as indicative of the tissue of origin. The synovial membrane is derived from connective tissue, the cells of which possess a dual potentiality, becoming by development either supportive or lining cells. The cells of a synovial tumor may exhibit varying degrees of functional differentiation, forming organoid structures resembling synovia. The source and mode of formation of the synovial fluid are not definitely known, but the experimental work of Vaubel (6) with tissue cultures supports the theory that it is produced by the living synovial cells. In some of the cases on record, and in the case here reported, a viscid mucinous fluid resembling synovial fluid has been found within the tumor. In most of the reported cases the tumors have been malignant, although a few (7) have been apparently benign. The following case is reported because of its well marked organoid growth tendencies, and as an example of a benign form of synovioma.