Autologous stem cell transplantation for relapsed and primary refractory myeloma.

The aim of this study was to evaluate the effectiveness of autologous stem cell transplantation for patients with relapsed or primary chemotherapy-refractory myeloma. Seventy-five patients, 50 men and 25 women, ages 33-68 years (median, 53 years), who underwent transplantation for relapsed or primary refractory myeloma were studied. Patients underwent transplantation 5-88 months (median, 23 months) after diagnosis of myeloma. The time to transplantation was significantly shorter in patients with refractory disease than for those with relapsed myeloma (median, 8 and 32 months, respectively; P < 0.001). Patients with primary refractory myeloma had a significantly lower plasma cell labeling index than those with relapsed disease (P = 0.008). There were no differences in overall and complete response rates between patients with primary refractory and relapsed disease. The median survival of the entire cohort from diagnosis was 53 months. Overall survival from transplantation among patients with relapsed myeloma receiving therapy, relapsed myeloma off therapy, and primary refractory myeloma was significantly different (P = 0.04), with median times of 12, 21 and 30 months, respectively. Progression-free survival also was different (P < 0.001), with median times of 7, 13, and 26 months, respectively. We conclude that overall and progression-free survival in patients with primary refractory myeloma appear better than in patients with relapsed disease and need further study.