Objective: To investigate immunoglobulin (Ig) and T cell receptor (TCR) gene rearrangements in bone marrow or peripheral blood of patients with non-Hodgkin's lymphoma (NHL), and to explore the potential clinical significance.
Methods: The Ig/TCR gene rearrangements in bone marrow or peripheral blood of 139 NHL patients were analyzed by using BIOMED-2 multiple primers system and Multiplex PCR assay.
Results: Ig clonality was detected in 85.4% (70/82) of chronic lymphocytic leukemia (CLL), including 46.3% (38/82) IgH rearrangement, 62.2% (51/82) IgK rearrangement and 1.2% (1/82) IgL rearrangement, and in 39.4% (13/33) of other categories of B-lineage NHL (B-NHL), including 33.3% (11/33) IgH and 39.4% (13/33) IgK rearrangements. TCR clonality was detected in 50.0% (12/24) of all definite T-lineage NHL (T-NHL), including 8.3% (2/24) TCRB and 45.8% (11/24) TCRG, no TCRD was detected. The detection rate of gene rearrangements of NHL diversed in different clinical stages \[36.4% in early stage (Ann Arbor stage I and II) and 45.6% in late stage (III and IV)\] and in different degrees of malignancy (40.0% indolent NHL and 45.6% aggressive NHL), but no obvious statistical significance was obtained (P > 0.05). The detection rate of bone marrow invasions of NHL (except CLL) with examinations of bone marrow smear under the microscope was 12.3% (7/57), much lower than the clonality testing (43.9%, 25/57) (P < 0.05). Sensitivity test showed that the sensitivity of malignant clonality testing by multiplex PCR was 3.12% - 6.25%.
Conclusions: The detection rate of gene rearrangements diverses in different clinical stages and degrees of malignancy of NHL, but the correlation has not been proved in this research. The sensitivity of multiplex PCR-based clonality testing is enhanced with the combination of BIOMED-2 primers system. It is more sensitive than the morphological examinations of bone marrow smear in detecting bone marrow invasions, and may provide a powerful strategy in the routine diagnosis and assessment after treatment.