Clinical features distinguishing lymphoma development in primary Sjögren's Syndrome--a retrospective cohort study.

OBJECTIVE: The objective is to determine the relationship between clinical features and non-Hodgkin lymphoma (NHL) development in primary Sjögren's Syndrome (pSS), taking recently designed disease activity/severity scores into account.

METHODS: Medical charts of pSS patients were retrospectively analyzed, scoring first and last visits with the (cumulative) EULAR Sjögren's Syndrome Disease Activity Index and counting extraglandular manifestations, comparing patients with and without NHL.

RESULTS: One hundred ninety-five patients were analyzed with a median follow-up of 92 months (range 12-256). Twenty-one patients (11%) had NHL. Associations of parotid gland enlargement (OR 2.84) and low C4 (OR 7.71) with NHL were confirmed. In NHL patients, development of purpura, peripheral neuropathy (PNP), and glomerulonephritis (GN) concurred with lymphoma in 3/3, 5/7, and 2/2 of cases, respectively. Otherwise, purpura and PNP were not associated with NHL later on. This suggests that these symptoms might represent paraneoplastic events (in 16%, 24%, and 100% of our cases, respectively). Presence of IgM-kappa clonal components was associated with lymphoma in 64% of cases. Disease activity/severity scores at first visit could not predict lymphoma development, nor was the pSS disease course significantly worse in patients with NHL.

CONCLUSIONS: In our cohort, no clinical manifestation or disease score could clearly select patients with subsequent lymphoma development. Presence of IgM-kappa clonal components and development of purpura, PNP, and GN should alert the clinician for the presence of lymphoma.