BACKGROUND: Peripheral blood mononuclear cells (MNCs) collected by leukapheresis contain hematopoietic stem and progenitor cells that provide autologous hematopoietic rescue after high-dose chemotherapy, an approach that offers a significant benefit to patients with recurrent Hodgkin's disease. However, patients with low MNC counts may require 10 or more standard leukapheresis procedures for the collection of sufficient cells for hematopoietic rescue. STUDY DESIGN AND METHODS: The effectiveness of steady-state large-volume leukapheresis (LVL; 15-35 L blood processed) was evaluated as a method for collecting MNCs for hematopoietic rescue in seven patients with recurrent Hodgkin's disease. LVL was performed on 2 consecutive days per week to collect 7 x 10(8) MNCs per kg. The circulating MNC counts on the first day of LVL and the total numbers of LVL, of MNCs collected, and of liters of blood processed were determined per patient. After high-dose chemotherapy and MNC transfusion, days to granulocyte and platelet engraftment were recorded. RESULTS: On the first day of LVL, patients had median circulating MNCs of 1536 (range, 504-3950) x 10(6) per L. The median number of LVL procedures per patient was four (range, 1.25-6), and the median L per kg of blood processed was 1.57 (range, 0.38-4.03). Simple regression analysis plotting L per kg against initial MNCs gave a curve with the equation y = e(1.42-(6.31 x 10E-4)x) (correlation coefficient = -0.97, R2 = 0.95, exponential fit). Without posttransfusion growth-factor support, median days to granulocyte engraftment were 19 (range, 12-26) and those to platelet transfusion independence were 34.5 (range, 10-57). CONCLUSION: LVL provides a useful method of collecting MNCs for hematopoietic rescue in patients with Hodgkin's disease. The patient's baseline MNC count provides a useful estimate of the volume required for LVL.