Studies evaluating the effects of previous chemotherapy on stem-cell yield and hematological recovery after autologous peripheral-blood progenitor-cell transplantation (PBPCT) have shown conflicting results. We have retrospectively analyzed 103 consecutive lymphoma patients treated with the BEAM regimen and autologous PBPCT. The impact of the different chemotherapeutic drugs (cumulative doses) on stem-cell yield and transplant-related toxicity was investigated. Highly significant differences in platelet recovery (>20 x 10(9)/l) were observed between patients receiving less or more than 750 mg/m(2) of etoposide before transplant (15 vs 29 days, P=0.001), and between patients receiving less or more than 1.2 x 10(6)/kg CD34(+) cells (27 vs 14 days, P<0.001). Differences in neutrophil engraftment between groups were not clinically significant. Pre-transplant cumulative doses of etoposide >750 mg/m(2) were associated with low CD34(+) cell collections on multivariate analysis. The actuarial incidence of transplant-related mortality (TRM) was 14% at 5 years. Pre-transplant cumulative doses of etoposide >350 mg/m(2) and previous administration of procarbazine were found to be independent prognostic factors for TRM.