Five per cent of patients with primary Sjogren's syndrome (pSS) develop 
malignant non-Hodgkin's lymphoma (NHL), usually of the mucosa-associated 
lymphoid tissue (MALT) and most frequently located in the major salivary glands. 
Rituximab (RTX), a chimeric monoclonal antibody against the CD20 molecule 
expressed on the surface of mature B cells that has been approved for the 
treatment of NHL, has been used to treat pSS-associated lymphoma. We have 
described two cases: one with MALT lymphoma in the parotid glands and the other 
with a rare thymus lymphoma accompanied by the rare complication of a bullous 
pneumopathy. Both were treated with RTX at haematological doses, which was 
unsuccessful in the patient with a salivary lymphoma; in the case of the patient 
with a thymus lymphoma, the mediastinum mass disappeared and did not relapse. 
Both patients experienced an improvement in the subjective symptoms of dryness, 
and their Schirmer's test and scialoscintigraphy results stabilised. The 
pulmonary bullae remained unchanged.