Risk of lymphoma

Lymphoma risk: Lymphoma is a very severe complication of primary Sjogren's syndrome: 5 to 10%;bf patients followed for more than 10 years will develop a lymphoma. Predictive factors include serum monoclonal immunoglobulins or cryoglobulins and a B clone population in accessory salivary glands. Typical clinical and histological presentation: Mucosal involvement (paroti d as well as gastric or pulmonary localizations) is frequent According to t he recent classification of lymphomas, most lymphomas developing in patient s with Sjogren's syndrome are B lymphomas of the marginal zone: MALT lympho mas or low-grade nodal monocytoid lymphomas which are sometimes not identif ied until transformation to the giant cell stage. Similarities with hepatitis C lymphomas: The pathophysiology of lymphoma in Sjogren's syndrome remains unknown. To date, there is no argument favoring a viral infection or a deregulation of a unique oncogene or anti-oncogene. Certain similarities between lymphomas in Sjogren's syndrome and lymphomas associated with hepatitic C virus would suggest a common pathogenisis: pos sibly a permanent stimulation of auto-reactive B cells carrying a surface i mmunoglobulin with rheumatoid factor activity in the target organs of the a utoimmune disease. These B lymphocytes would then proliferate secondarily.