Objectives To analyse the epidemiological, clinical and analytical features at diagnosis and the use of the European systemic activity index (ESSDAI) to predict the development of cancer in a large cohort of Spanish patients with primary Sjogren syndrome (SS).
Methods The GEAS-SS multicenter registry was formed in 2005 with the aim of collecting a large series of Spanish patients with primary SS, and included thirteen Spanish reference centers with substantial experience in the management of SS patients. By January 2015, the database included 1216 consecutive patients fulfilling the 2002 classification criteria for primary SS. ESSDAI scores were retrospectively calculated at diagnosis. Disease activity states (DAS) were defined according to the baseline ESSDAI score (low DAS for an ESSDAI <4, moderate DAS for an ESSDAI between 5 and 13, and high DAS for an ESSDAI higher than 13). Cancer was categorized as hematological or solid neoplasia.
Results After a mean follow-up of 114 months, 84 (7%) patients developed solid cancer and 52 (4%) hematological neoplasia. The following baseline features at diagnosis were associated with the development of hematological neoplasia: male gender (19% vs 6%, p<0.001), age at diagnosis (59 vs 54 yrs, p<0.001), baseline systemic activity (75% vs 51%, p=0.001), neutropenia (19% vs 9%, p=0.028), C3 values <0.82 g/L (19% vs 10%, p=0.048), C4 values <0.07 g/L (24% vs 12%, p=0.02), monoclonal serum band (27% vs 8%, p<0.001) and cryoglobulins (30% vs 9%, p<0.001). In contrast, only age (59 vs 54 yrs, p<0.001) and neutropenia (21% vs 9%, p=0.001) were related to the development of solid neoplasia. High systemic activity (high-DAS) was found in a higher frequency in patients who developed hematological in comparison with those who developed solid neoplasia or those without neoplasia (79% vs 24% vs 21%, p<0.001).
Conclusions Systemic and biological activity is closely related to the development of lymphoma in primary SS. Etiopathogenic factors such as B-cell hyperactivity and monoclonal, cryoglobulinemic-driven immunological responses have a dual effect, enhancing the risk of development of both systemic involvement and hematological neoplasia, but not the risk of solid neoplasia, whose development is independent of systemic Sjögren.
Disclosure of Interest None declared