Incidence and epidemiology of non-Hodgkin lymphoma and risk of second malignancy among 22 466 survivors in Israel with 30 years of follow-up.
Previous studies have shown an increase risk of second malignancies after non-Hodgkin's lymphoma (NHL), which is probably related to a combination of factors including genetic predisposition, molecular background, host immunological status and therapy administered. Here, we determined the incidence of NHL and risk of second solid tumours and haematological malignancies among survivors of NHL diagnosed in Israel during 1980-2011. Data were collected from the records of the Israeli National Cancer Registry. The total cohort of 24 666 NHL-patients included 22 601 Jews and 2065 Arabs. Median age of diagnosis for Jews was 61.3 years and 48.2 for Arab patients. Of the Jews with NHL, 11 265 (50%) were of European-American origin, 5005 (22%) Asian or African and 6114 (27%) were born in Israel. Second cancers were recorded in 2010 NHL survivors, 1918 Jews and 92 Arabs, representing a rate of 8.5%, and 4.5% o, respectively. Second malignancies in all recorded sites were more frequent than in the general population, with a standardized incidence ratio (SIR) of 1.28 for Jewish men, 1.25 for Jewish women, 1.73 for Arab men and 1.98 for Arab women. This higher risk was even more pronounced for the 309 cases with secondary haematological malignancies (secondary haematological malignancies of 1.97, 1.81, 4.48 and 4.15, respectively). Our findings show that there is an increased risk of second malignancies occurring after diagnosis of NHL in Israel, particularly for haematological malignancies such as leukaemia and NHL. The differences we report in the incidence of NHL and the types of second malignancies occurring among Jews and Arabs suggest that ethnicity and genetic susceptibility may be important relevant risk factors. Copyright © 2016 John Wiley & Sons, Ltd.