Indolent non-follicular non-Hodgkin lymphomas (INFL) are a heterogenous subset whose treatment has been poorly investigated. In this context we have evaluated the efficacy and safety of combined fludarabine and cyclophosphamide (FC) upfront therapy. Sixty-three patients with advanced INFL were enrolled in the study. Therapy consisted in FC combination (25 and 250 mg/m(2), i.v., respectively, for three consecutive days) every 28 days for six courses. After histological review, 61 patients (36 men, median age 64 years, range 40-70 years) were evaluated (22 small lymphocytic, 11 lymphoplasmacytic, 25 marginal zone and 3 CD5-negative non-Hodgkin lymphomas not otherwise specified). Further two patients were excluded for lack of essential data; six patients were withdrawn before the third cycle because of WHO grade III and IV toxicity. At the final evaluation, the overall response rate was 83% with 40.7% of complete remission. Intention-to-treat analysis showed that at the median follow-up of 36 months, overall survival, progression-free survival and failure-free survival were respectively 78%, 60% and 46%; remission duration among the 49 patients achieving complete remission/partial remission at the end of treatment was 65% (44-78) without significant differences between the main histotypes. The most frequent grade III and IV toxic events were haematological (neutropaenia 34%, anaemia 18% and thrombocytopaenia 11%) and infectious (10%). FC is effective for advanced untreated INFL. Early deaths and haematological toxicity suggest careful patient selection and monitoring.