Epidemiology of Non-Hodgkin's Lymphoma in India.

Non-Hodgkin's lymphoma (NHL) is a common hematological malignancy. The age-adjusted incidence rates for NHL in men and women in India are 2.9/100,000 and 1.5/100,000, respectively. These are about one fourth of the incidence rates reported from Western Europe or North America. Within India, the incidence is several-fold higher in urban cancer registries compared to rural areas; the incidence being higher in metropolitan cities and Indian immigrants suggesting that urban lifestyles and economic progress may increase the cancer incidence. Compared to developed nations, the key differences in the presentation in India include: median age of 54 years (almost a decade less), higher male to female ratio, higher proportion of patients with B-symptoms (40-60 vs. 20-30%), poor ECOG performance status (≥2) at diagnosis (50 vs. 20-30%), higher frequency of diffuse large B-cell lymphomas (60-70 vs. <40%), lower frequency of follicular NHL (<20 vs. 30-40%) and T-cell type in 10-20 vs. <10%. The estimated mortality rate due to NHL is higher in India than in North America and Western Europe. Diagnostic and treatment delays, incorrect diagnosis and inappropriate or suboptimal treatment may be possible reasons for the poor outcome. Any improvement in the outcomes for NHL in India will require a nationwide approach, e.g. creation of several regional and district-level centers with expertise in lymphoma management. Collection of data on patient- and disease-related characteristics, treatment outcome, development of infrastructure, centralized review of histopathology subtype, novel treatment protocols, rigorous follow-up, training of staff, and financial support towards treatment could be possible strategies to improve the outcome.