Running in the family: MALT lymphoma and autoimmune disease in mother and daughter.

Gastric B-cell lymphoma of the mucosa associated lymphoid tissue (MALT) lymphoma is one of the most common forms of extranodal lymphoma. In addition to infection with Helicobacter pylori (H. pylori), the presence of an underlying autoimmune disease has also been associated with MALT lymphoma development. To date, no familial predisposition for MALT lymphomas has been reported as opposed to other types of lymphoma. A 65-year-old woman was admitted at our institution in 1998 with a diagnosis of H. pylori positive gastric MALT lymphoma and the presence of chronic autoimmune thyroiditis was established on further work-up. H. pylori eradication did not result in regression of the lymphoma and RT-PCR showed the presence of the t(11;18)(q21;q21) translocation. About 1.5 years after H. pylori eradication, chemotherapy with cladribine resulted in complete remission. Due to lymphoma recurrence 13 mo later, radiotherapy to the stomach (46 Gy) resulted in minimal residual disease without further progression. The patient developed a second malignancy (Epstein-Bar virus-associated anaplastic large cell lymphoma in the mediastinum) in 2004 which initially responded to two courses of chemotherapy, but she refused further therapy and died of progressive lymphoma in 2006. In 2008, her 55 years old daughter with a long standing Sjögren's syndrome was diagnosed with MALT lymphoma of the right parotid, but no evidence of gastric involvement or H. pylori infection was found. Currently, she is alive without therapy and undergoing regular check-ups. To our knowledge, this is the first report of MALT lymphoma in a first-degree relative of a patient with gastric MALT lymphoma in the context of two autoimmune diseases without a clearly established familial background.