DISEASE CHARACTERISTICS: Histologically documented non-Hodgkin's lymphoma Needle or core biopsy not acceptable as sole means of diagnosis No mantle cell or transformed lymphoma One of the following International Working Formulation (IWF) histologic subtypes required: Small lymphocytic with absolute lymphocytic count less than 5,000 (IWF A) Follicular, predominately small cleaved cell (IWF B) Follicular, mixed (IWF C) Follicular, large cell (IWF D) Diffuse, small cleaved cell (IWF E) Diffuse, mixed (IWF F) Diffuse, large cell (IWF G) Large cell, immunoblastic (IWF H) Recurrent or refractory disease treated with no more than 4 prior chemotherapy regimens Rebiopsy of a node at first relapse recommended Prior etoposide (oral or intravenous) allowed if given for no more than 5 days every 3 weeks The following are considered 1 prior therapy each: Identical drugs given on 2 different schedules Bone marrow transplant preparative regimen (single cycle of chemotherapy used solely to mobilize peripheral blood stem cells considered part of preparative regimen) Ineligible for protocol CLB-9551 (aminocamptothecin) Measurable disease by physical exam or imaging study required Indicator lesion larger than 1 x 1 cm No prior radiotherapy to indicator lesion unless progression clearly documented The following are not considered measurable: Barium study Ascites or pleural effusions Bony disease Bone marrow involvement No known parenchymal or leptomeningeal CNS disease Lumbar puncture not required prior to study