Epidemiologic findings of non-Hodgkin lymphoma (NHL) in Puerto Rico (PR).

Abstract

e19505 Background: NHL was the 6th leading cause of cancer among USA Hispanics from 2005-2009. There is limited literature about lymphoma among Hispanics outside USA. The goal of this study is to assess the incidence, trends, survival and histological distribution in a population of Puerto Ricans and compare the results with USA. We report data on 3,184 pts diagnosed with lymphoma from the PR Cancer Center Registry during 2004-2009. Methods: Rates of sex-specific, age-adjusted incidence (AAIR) with 95% CI were estimated and standardized by age-adjustment according to the world standard population. The annual percent change (APC) using joint point regression analysis was determined. Data was compared with the SEER Cancer Statistic Review (1975-2009). Results: NHL comprises 82% of lymphomas in PR. As in USA it is the 6th most common cancer in males and the 7th in females. AAIR per 100,000 for NHL in PR was lower as compared to USA: 11.8 for males in PR vs 23.2 in USA, while for females it was 9.8 in PR vs 16.2 in USA. Despite a lower AAIR, there was an increase of 3.2% APC in NHL for PR during 2004-09. When analyzed according to gender, this rise was attributed only to females: 6.3% increase vs 0.5% in males. In contrast, in USA a decreasing trend in APC (-0.8%) was seen for females. B cell lymphomas in PR comprise 92% of NHL and 90% in USA. DLBCL represents 53% of all B cell-NHL in PR which is markedly higher than the 28% reported in USA. Follicular NHL in PR represents 22% of all NHL, in contrast to 32% in USA. There is a noticeable difference in the distribution of T cell lymphoma subtypes in PR as compared with USA, with a higher number of cases of anaplastic large cell and cutaneous T cell lymphomas and a lower frequency of angioimmunoblastic T cell lymphomas in PR. In terms of relative survival rate (RSR), our results are comparable to USA. Follicular NHL has a 5 year RSR of 74% in PR vs 75% in USA and DLBCL has a 5 year RSR of 47% in PR, vs 50% RSR in USA. Conclusions: Despite a lower AAIR, a significant increasing trend of NHL was observed in PR and we determined this to be exclusively observed among females. We also identified marked differences between the distribution of histologic subtypes of NHL in PR and USA. We plan to assess which histologic subtypes are increasing and in which regions of the island.