OBJECTIVES: Data on costs of care and typical care paths for patients with malignant lymphomas in Germany are scarce. The aims of this prospective health economic survey are to identify typical clinical pathways and assess the costs and clinical benefits of different treatment settings and modalities for patients with newly diagnosed malignant lymphomas. METHODS: The recruitment of patients for this project started in 2000 and will be continued through 2003 in the Cologne and Saarland regions, Germany. Data on resource consumption and outcomes are collected prospectively by means of a patient book and a health economic questionnaire. For the cohort of the one-year pilot phase, hospital costs and costs of chemotherapy for the first 6 months since initial diagnosis were calculated. RESULTS: 192 patients have been recruited during the pilot phase. Of these, 22 (11,5%) were diagnosed with Hodgkin's disease (HD), 111 (57,8%) with non-Hodgkin's lymphoma (NHL), 36 (18,8%) with chronic lymphatic leukemia (CLL) and 18 (9,4%) with multiple myeloma (MM) (5=2,6% undefined). The treatment setting was as follows: 72 (43,6%) of the patients were treated in an outpatient setting, 37 (22,4%) in an inpatient setting and 56 (33,9%) in a combined inpatient and outpatient setting. 54 (33,5%) patients were treated within and 74 (46,0%) outside of clinical trials (33=20,5% undefined). For HD patients, mean hospital costs and mean costs of chemotherapy during the first 6 months after initial diagnosis were € 6.336,95 and € 10.039,73 respectively, for NHL patients € 9.787,15 and € 6.720,93, for CLL € 1.055,31 and € 749,04 respectively, and for MM patients € 9.016,12 and € 4.870,57. CONCLUSIONS: The continuation of this project will make it possible to determine cost-of-illness and cost-effectiveness ratios of different treatment modalities for patients with malignant lymphomas and to develop guidelines for clinical pathways.