Recent results suggest that B cells may have multiple pathogenic roles in systemic sclerosis (SSc) and there may be increased incidence of B cell lymphomas in SSc. Here, we assessed the prevalence of lymphomas in a large SSc cohort. We analyzed data of 218 Hungarian patients undergoing follow-ups in our institutions between 1995 and 2007. During this follow-up period, there were three SSc patients, who eventually developed B cell lymphoma. The first case is a woman with diffuse cutaneous form of SSc (dcSSc) including pulmonary, cardiac, gastrointestinal, and renal manifestations and anti-topoisomerase I antibody positivity. B cell chronic lymphocytic leukemia (B-CLL) with Zap70 expression (Rai I stage) developed 2 years after the onset of SSc. The second case is a woman with dcSSc presenting with pulmonary, cardiac, and gastroesophageal manifestations. Twenty-one months after disease onset, a chronic small lymphocytic B cell non-Hodgkin's lymphoma was diagnosed from retroperitoneal lymph nodes. Our third case is a woman with dcSSc and no internal organ manifestations. She also developed Zap70-positive B-CLL, stage Rai I 9 months after the onset of SSc. Thus, there were three cases of B cell lymphoma among our 218 SSc patients (1.38%). The association of scleroderma and non-Hodgkin's lymphoma may be a rather uncommon feature; however, the incidence of lymphoma among Hungarian SSc patients may be 1.9-2.5 times higher than that in the general population. In our three patients, B cell lymphoma developed within 2 years after the onset of SSc. Altered B cell function implicated in the pathogenesis of SSc may lead to the development of lymphoid malignancies.