High dose chemotherapy without hematopoietic cell support for the treatment of refractory lymphoma

Conventional dose combination chemotherapy for patients with relapsed or refractory lymphoma is rarely curative. High dose chemotherapy followed by hematopoietic progenitor cell transplant (HPCT) has a clearly defined role in patients who have first relapsed after standard CHOP chemotherapy for lymphoma. However, the role of HPCT is less well defined for patients with chemo-resistant, or chemo-refractory disease. Sixteen patients (15 Non-Hodgkin's, 1 Hodgkin's Disease) were entered into a phase II study to determine if a dose intensive induction regimen in heavily pre-treated refractory lymphoma patients could permit further consolidation with HPCT. The primary endpoints were survival, response, toxicity, and resource utilization. The regimen consisted of continuous infusion etoposide 1 or 2 gm/m²/72 hours, idarubicin 12 mg/m²/d for 3 days followed by cytarabine 2 gm/m²/72 hours on days 8,9, and 10 (VIC). Fifteen patients were evaluable for objective response. The overall response rate was 53% with 7 patients achieving a partial response and 1 patient achieving a complete response. Of the 8 responders, 6 patients subsequently received high dose chemotherapy followed by HPCT (4 autologous, 2 allogeneic). The median survival was 176 days for the non-responders contrasted with 722 days for the responders. The average duration of hospitalization was 38 days. Toxicity was mainfest primarily as mucositis with a median grade of 3 among the first 13 patients, and a median grade of 2 in three subsequent patients who received an etoposide dose of 1 gm/m²/72 hours. All patients had an episode of neutropenic fever and 5 patients developed clinically significant pneumonitis during therapy. The VIC regimen is active in the treatment of chemo-refractory lymphoma with clinically significant differences in survival for patients who respond to therapy. Further modifications to the regimen could include the addition of a topoisomerase I inhibitor for synergy with etoposide, and using VIC as part of a tandem transplant regimen where response to VIC would allow further therapy with a myeloablative induction followed by HPCT.