Divya Bala Thumaty1, Sohan Singh Mandloi1, Yadav Nisha1, Smita Kayal1, Prasanth Ganesan1, Sajini Elizabeth Jacob2 Debdatta Basu2,Biswajit Dubashi 1*.
1 Department of Medical Oncology, 2 Department of Pathology, Jawaharlal Institute of Post Graduate Medical Education & Research (JIPMER), Puducherry, India.
Introduction: Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin Lymphoma (NHL), constituting up to 40% of all NHL cases globally. DLBCLs represent a heterogeneous group of neoplasms rather than a single clinicopathological entity. Over the past decade, recognition of germinal centre , activated B-cell lymphomas and double hit /double expressor lymphomas have gained attention due to the varied prognosis and predictive outcomes in each of these subtypes. In this series of patients with DLBCL from our insititute, we analysed the outcomes and clinical features based on the cell of origin.
Methodology: Medical case records of all newly diagnosed DLBCL patients with age greater than 18 years, treated at RCC JIPMER from January 2015 to July 2017 were analysed for this study. Institute Ethical approval was obtained from the Institute Ethics Committee, JIPMER. Details about clinical presentation, cell of origin subtype, treatment outcomes in terms of response and survival were obtained from the records. Staging was done with CT scan or PET CT scan. All statistical analyses were performed by using SPSS 19 version software. Kaplan-Meier curves were used to determine survival.
Results: During the study period, a total of 95 patients were diagnosed to have NHL, DLBCL subtype. Immunophenotypic subtyping was available for 71 of them. We described three groups of patients : germinal centre type, non – GCB (activated B cell type) and one-third of them with unknown immuno-phenotyping. Median age at diagnosis was 56 years and there was no difference in median age between GC and non-GC subtypes. Approximately 44% of patients had extra-nodal disease, stomach being the commonest site. 40% had stage III/IV disease. Bulky disease and predominantly extra-nodal presentation was seen more in those with non-GCB subtype(46% vs 20% and 36% Vs 29% respectively). Rituximab was used in 75% of the patients with DLBCL. With a median follow up duration of 17 months, overall survival in GCB vs ABC – 80.6% vs 69.8% (p= 0.64) at 18 months.
Disease free survival at 18 months was, 70.1% vs 56.2% ( p=0.38) in GCB vs ABC.
Conclusion: Multiple studies from each regional cancer centre have described their outcomes in the past 2-3 years. This is the first of the data among DLBCL patients reported from India where outcomes are described based on the cell of origin. Survival was better in GCB subtype and Rituximab was used in 75% of patients despite the resource constraints.
A larger multicenter, prospective study of outcomes in Indian population is required to understand the epidemiology and outcomes of DLBCL patients and to deliver personalized accessible and affordable treatment regimen to maximum number of patients.