Index case of synovial metastasis in a patient with transitional cell carcinoma of the bladder.

Synovial metastasis is a rare presentation with only a few reported cases in the published literature. A majority of cases of malignant synovitis have a primary lung or colorectal origin. It carries a poor prognosis with an average survival of approximately 5 months from diagnosis. The treatment options are limited to palliative approaches, which highlight the aggressive nature of the presentation as well as the necessity for early recognition. We report an index case of synovial metastasis of the knee joint in a patient with progressive transitional cell carcinoma of the bladder and review the literature with respect to synovial metastasis. © BMJ Publishing Group Limited 2020. No commercial re-use. See rights and permissions. Published by BMJ.