Preliminary report of Ki-67 reactivity in synovial chondromatosis of the temporomandibular joint: An immunohistochemical study

Abstract

BackgroundSynovial chondromatosis (SC) is rare benign condition characterized by the formation of metaplastic cartilaginous nodules in the synovial membrane and joint space. Cartilaginous nodules from and may become pedunculated and detached from the synovial membrane, so becoming loose bodies within the joint space. PurposeThe aim of this study was to determine the proliferative activity of loose body and synovial membrane of SC in temporomandibular joint by using Ki-67 antibody. Material and methodsWe obtained 4 specimens (4 female) of released loose body and 2 specimens of synovial membrane with attached loose bodies by surgical operation. The specimens were fixed in 10% formalin solution, and embedded in paraffin. The immunohistochemical study was carried out using an anti-human Ki-67 monoclonal antibody. The sections were visualized by 3, 3′-diaminobenzidine-tetrahydrochloride (DAB). ResultsThe expression of Ki-67 was scarcely detected in all cases of loose bodies. In second phase cases, the mild expression of Ki-67 was detected at both cases of synovial membrane which were attached loose bodies. ConclusionThese results suggested that released loose bodies into the joint compartment did not have independent proliferating activity. However, the synovial membrane may play a very important role in the proliferation of the loose bodies.