Immunoglobulinopathies in patients with angioimmunoblastic T-cell lymphoma.

Aim: The aim of the study was to characterize quantitative and qualitative immunoglobulinopathies in patients with AITL at the onset of the disease.
Materials and Methods: 55 patients with newly diagnosed AITL were enrolled in the study, the male/female ratio was 30/25; median age was 61 (29-81) years. Diagnosis was based on standard WHO criteria. Immunochemical studies of blood serum included serum protein electrophoresis/immunofixation, nephelometric quantification of total immunoglobulins, serum free light chain assay.
Results: Quantitative and qualitative immunoglobulinopathies were determined in 49 (89,1%) of 55 pts. Quantitative immunoglobulinopathies were revealed in 47 (85.5%) of 55 cases, qualitative - in 14 (25,5%). Combination quantitative and qualitative immunoglobulinopathies was observed in 12 (21,8%) of 55 pts. The detected immunoglobulinopathies were divided into 4 groups: polyclonal hypergammaglobulinaemia, hypogammaglobulinaemia, oligoclonal gammapathy, and monoclonal gammapathy. Polyclonal hypergammaglobulinaemia was marked in 41 (74.5%) of 55 pts, elevated level of IgG was determined in 27 (49,15%) of 55 cases, IgM - in 18 (32,7%) and IgA - in 21 (38.2%). Interestingly, polyclonal IgE hypergammaglobulinaemia was detected in 12 (48,0%) of 25 cases of performed studies. Hypogammaglobulinaemia was detected in 8 (14,5%) of 55 cases. Oligoclonal gammapathy was determined in 4 (7.3%) of 55 pts. Monoclonal gammapathy was revealed in 11 (20,0%) of 55 cases. The amount of monoclonal immunoglobulin varied from 2.6 to 14.1 g/l. Monoclonal immunoglobulin Gk was detected in 5 of 11 pts, Gλ - in 2, Mλ - in 2, Mk - in 2. Monoclonal gammapathy was accompanied by polyclonal hypergammaglobulinaemia in 9 of 11 cases, hypogammaglobulinaemia - in 2.
Conclusion: Quantitative and qualitative immunoglobulinopathies are observed in most patients at the onset of AITL. Quantitative abnormalities were determined more often than qualitative. Monoclonal gammapathy can be a manifestation of lymphoproliferation and other concomitant disorders. The prognostic value of immunochemical parameters is still unclear and requires dynamic observation and study.