HIGH-DOSE THERAPY WITH PERIPHERAL-BLOOD PROGENITOR-CELL TRANSPLANTATION IN LOW-GRADE NON-HODGKINS-LYMPHOMA

It was the objective of our study to evaluate the efficacy of a sequen tial high-dose therapy with peripheral blood progenitor cell (PBPC) su pport in patients with low-grade non-Hodgkin's lymphoma (NHL). Since J uly 1991, 48 patients (23 male/25 female) with a median age of 43 year s (range 26-55) were included in the study. At the time of entry, 28 p atients were in first and seven in second or higher remission, Twelve patients had relapse of disease and one patient had tumor progression, PBPC were collected during granulocyte colony-stimulating factor (G-C SF)-enhanced leukocyte recovery following treatment with high-dose cyt arabine and mitoxantrone (HAM). A median of two leukaphereses (range 2 -7) resulted in 6.9 x 10(6) CD34(+) cells/kg (median, range 2.1 x 10(6 )-38.8 x 10(6)), A comparison was made between the harvests obtained f rom patients in first remission and those from patients in second remi ssion, in relapse or progressive disease. Patients mobilized in first remission tended to have a greater collection efficiency for CD34(+) c ells comprising a significantly greater proportion of more primitive C D34(+)/Thy-1(+) progenitor cells. Conversely, leukapheresis (LP) produ cts collected during first remission contained a significantly smaller proportion of CD34(+)/CD45RA(+) cells and CD34(+)/c-kit(+) cells, sub sets which reflect a more differentiated progenitor cell stage. Follow ing high-dose therapy and PBPC autografting, the median time to reach platelets greater than or equal to 20 x 10(9)/l and neutrophils greate r than or equal to 0.5 x 10(9)/l was 12 and 13 days, respectively. Two patients died of treatment-related toxic organ failure, Thirty-nine p atients are alive in remission after a median follow-up time of 15 mon ths (range 1-31), while seven patients relapsed between 5 and 29 month s posttransplantation. Except for one patient autografted in first rem ission, the patients with relapse had a history of previous relapse or progressive disease. Since the probability of disease-free survival a ppears to be related to the disease status at the time of autografting , PBPC-supported high-dose therapy including total body irradiation sh ould be investigated further for patients with low-grade NHL while the y are in first remission.