A pilot phase I/II study was conducted as a single-institute trial for evaluation of the feasibility and efficacy of a new salvage chemotherapy, CHASE, for patients with refractory or relapsed lymphoma . The CHASE regimen, consisting of cyclophosphamide, cytosine arabinoside, etoposide, and dexamethasone, was administered every 3 weeks in a maximum of 5 courses. A total of 16 patients were eligible and registered for this study. Myelosuppression was the major toxicity. Although grade 4 leukopenia and grade 3 thrombocytopenia were identified in 15 and 16 patients, respectively, duration of the nadir was brief (median, 3 days). Nonhematological grade 4 toxicity was not observed, and transient elevations of bilirubin and grade 3 aspartate aminotransferase/alanine aminotransferase (AST/ALT) were observed in 2 and 3 courses, respectively, in a total of 57 courses. Complete and partial response rates were 71.4% (10/14) and 7.1% (1/14), respectively. The median percentage of maximal CD34+ cells was 6.1% on day 15, and a median number of 1.88 x 10(6) CD34+ cells/kg per apheresis were obtained. Thirteen patients received high-dose chemoradiotherapy followed by autologous peripheral blood stem cell transplantation. With a median follow-up time of 36 months from the start of CHASE, the overall survival rate for the 16 patients was 66.6%. These results indicated that CHASE is a safe and effective salvage regimen for malignant lymphoma, has sufficient mobilizing effect on peripheral blood stem cells, and warrants further phase II study.