Extranodal Non-Hodgkin's lymphomas - A retrospective review of clinico-pathologic features and outcomes in comparison with nodal Non-Hodgkin's lymphomas

Objective: The primary objective of this study was to analyze the anatomic distribution, clinical features and outcome of Diffuse large B-cell lymphoma (DLBCL) patients according to the primary site (extranodal vs. nodal) with applicability of International Prognostic Index (IPI). Methodology: A retrospective review (1988 to 2004) of 557 cases of DLBC. Results: The median age was 48.7 ± 15.3 years; M:F ratio was 2:1. The distribution according to the primary site was: lymph node (N-NHL), 322 cases (58%) of which 145(44%) were stage IV, 76 (23%) stage III, 60 (18%) stage II and 47 (15%) stage I. The extra nodal sites (EN-NHL) 235 (42%) cases included gastro-intestinal tract (44%), upper aerodigestive tract (19%), bones (8%), spine (5%), and unusual sites less than 3% each as breast, CNS, testis, lungs and skin. The median survival rate was 4.8 years and 6.3 years in N-NHL and EN-NHL respectively. In the latter this varied greatly depending on the primary site and stage of disease at presentation. In the univariate analysis factors associated with good prognosis were: age less than 60 years, early stage (I-II), extranodal involvement primarily gastric or bone, 0-1 extranodal site, 0-1 performance status, lack of B symptoms and normal LDH level. In the multivariate analysis age, performance status, stage of disease and level of LDH were the main variables predicting overall survival; no nodal or extranodal site maintained their prognostic value. Conclusion: Patients with EN-NHL present more frequently with early stage disease then those with N-NHL; overall survival in both groups largely depended on IPI and not on the site of origin of the malignancy.