High degree of occult tumor contamination in bone marrow and peripheral blood stem cells of patients undergoing autologous transplantation for non-Hodgkin's lymphoma.

Twenty patients with non-Hodgkin's lymphoma (NHL), primarily intermediate-and high-grade, were evaluated for evidence of bone marrow (BM) or peripheral blood stem cell (PBSC) lymphoma contamination using tumor-specific oligonucleotide-polymerase chain reaction (TSO-PCR). Patients were enrolled in a single-institution study comparing PBSC and bone marrow transplantation (BMT) for relapsed NHL. A molecular marker (CDR3 rearrangement, T cell beta receptor [TC beta R] rearrangement, or BCL-2/IgH rearrangement) was identified from analysis of the diagnostic tissue in 17 of 20 patients. Prior to undergoing BMT, 14 of 17 patients had PCR evidence of lymphoma involvement of either BM (11/17) or PBSCs (9/11). No decrease was found in the frequency of contamination of PBSCs compared with BM. In one patient, quantitative competitive PCR (C-PCR) identified a three- to tenfold greater quantity of contamination in the BM compared with PBSC. All evaluated patients (6/6) with contamination prior to BMT had persistence of marrow contamination following BMT. Our data demonstrate that TSO-PCR can generate a molecular marker for the majority of patients with intermediate- and high-grade NHL. In addition, we identified a high rate of occult lymphoma involvement in both BM and PBSC. As demonstrated by C-PCR, however, quantitative differences may exist in contamination of BM and PBSCs.