TNF and synovial sarcoma: To date, no conclusions can be drawn in patients treated with anti-TNF- α with a misdiagnosed or concomitant MF/SS, owing to the presence in the literature of MF/SS cases unmasked by the use of anti-TNF-α, cases that progressed after biological treatment administration, and cases without clinical progression after anti-TNF-α treatment [242,243,244,245,246,247].