The American College of Rheumatology (ACR) and the European League against Rheumatism (EULAR) classification criteria, which still have a paramount role in the diagnosis of SS, include both a serological (presence of anti-SSA antibodies) and a histological domain (evidence of lymphocytic sialadenitis on a labial gland biopsy) [5]. Here, TRIM21 is linked to synovial sarcoma.