Mantle cell lymphoma (MCL) has a poor prognosis with often short and incomplete remissions. We aimed to test the efficacy and tolerability of gemcitabine in treating MCL. Gemcitabine was given in doses of 1000 mg/m(2) as a 30 min infusion on days 1 and 8 of each 3 week cycle for a maximum of nine cycles. Eighteen patients with a median age of 70 years were recruited. MCL was newly diagnosed in half of patients and relapsed in the remainder. Fifteen patients had Ann Arbor stage IV. The best-recorded responses were 1 CR (complete remission), 4 PRs (partial responses), 8 SDs (stable diseases) and 4 PDs (diseases progression). The response rate (RR) (CR + PR) was 5 (28%; 95% confidence interval: 7.1, 48.5). The patient achieving a CR had stage IV disease. Most haematological adverse events occurred during the first chemotherapy cycle. Three patients developed non-haematological serious adverse events: dyspnea, glomerular microangiopathy with haemolytic uremic syndrome (HUS) and hyperglycaemia. The median time-to-progression and treatment response duration (TRD) was 8.0 (95% confidence interval: 5.5, 9.3) and 10.6 (95% confidence interval: 5.5, 10.9) months, respectively. We conclude that Gemcitabine is well tolerated, moderately active and can induce disease stabilization in patients with MCL.