Emergence of Oligoclonal Bands in Association with the use of Chemotherapy and Hematopoietic Stem Cell Transplantation.

Multiple myeloma (MM) is a rare malignant condition with an abnormal clonal proliferation of plasma cells in the bone marrow. Chemotherapy and Hematopoietic Stem cell transplantation (HCT) are the main modalities of myeloablative therapy. The study aimed to determine the frequency of oligoclonal bands (OB) in multiple myeloma patients receiving primary therapy alone with chemotherapy as well as patients undergoing HCT at a single institution. The clinical and laboratory records of 76 MM patients were reviewed who underwent HCT from January 2012 to January 2019. Another 74 cases receiving chemotherapy alone, were also reviewed. In total 85 patients were selected by the availability of at least 3 serial immunofixation electrophoresis(IFE) results in non-transplanted cases and 2 post-transplant IFE results in the HCT cases after attainment of very good partial response(VGPR). 40 patients were non transplanted cases while 45 patients underwent HCT. Oligoclonal bands emerged in twenty-four (28%) patients 15% (6/40) of the patients treated without HCT and, 40% (18/45) of patients treated with HCT from their respective cohorts. To conclude, this is the first Indian report showing a higher frequency of oligoclonal response in patients in VGPR attained after hematopoietic stem cell transplantation versus chemotherapy. This difference could be due to a stronger immune reconstitution, or graft vs. host reaction, or autoimmune response to myeloma antigens and may not be an active disease process or relapse. However to determine the prognostic impact of OB further investigations and follow-ups are required.