CALR and synovial sarcoma: In addition, previous reports have detected autoantibodies other than ACA, anti-Ro/SS-A, anti-La/SS-B and rheumatoid factor in more than 50% of ACA+/SS patients [5], whereas in our study none of the patients in this group presented anti-Scl 70, anti-U1RNP or anti-Sm autoantibodies.