Successful peripheral blood stem cell mobilization with etoposide (VP-16) in patients with relapsed or resistant lymphoma who failed cyclophosphamidemobilization

High-dose chemotherapy (HDCT) followed by autologous blood stem cell transp lantation is considered the treatment of choice for patients with relapsed or resistant aggressive non-Hodgkin's lymphoma (NHL) or Hodgkin's disease ( HD), However, several authors report failure of standard mobilization regim ens in 29% to 56% of these patients making the completion of HDCT impossibl e and as a result, negatively influencing long-term outcome, Thus, effectiv e new regimens for patients failing initial mobilization are needed. Here w e report the results of using etoposide as a mobilizing agent in 16 patient s with primary resistant or relapsed malignant lymphoma who had failed prio r mobilization of peripheral blood stem cells (PBSC) with cyclophosphamide (4 g/m(2)) followed by G-CSF. The use of etoposide 500 mg/m(2) (days 1-4) G-CSF resulted in the successful collection of adequate numbers of PBSC wi th a median harvest of 3.6 x 10(6)/kg (range 2.2-12.6) CD34(+) cells in all 16 patients, In 7/16 (44%) patients, the target yield of at least 2.0 x 10 (6) CD34(+) cells was harvested by a single apheresis and the maximum numbe r of separations for all patients was two. No excessive toxicities appeared , allowing all patients to proceed to myeloablative chemotherapy, In additi on, median peak values of circulating CD34(+) cells were significantly high er after etoposide as compared to cyclophosphamide (49.2/mu l vs 4.7/mu l; P = 0.0004), These results indicate that etoposide + G-CSF is a highly effe ctive mobilization regimen in patients who have failed cyclophosphamide mob ilization.