Abstract 2535: The difference in the incidence and the trend of hematologic malignancies in Japan and the United States.
Authors: Chihara Dai , Morton Lidsay , Ito Hidemi , Matsuda Tomohiro , Shibata Akiko , Sobue Tomotaka , Weisenburger Denis D. , Matsuo Keitaro 
Published: August 2014

Abstract
Background: The hematologic malignancies are a collection of heterogeneous diseases with diverse epidemiologic features for which a detailed classification of disease subtypes has evolved dramatically. The incidence of a malignant disease reflects the genetics and cumulative exposure to the environment of a population. Therefore, evaluation of the incidence and trend of a disease in different populations may provide insights into the etiology and pathogenesis of that disease. However, no detailed data based on population-based cancer registry in Asia to see each disease entities are available. Aims: The aim of this study is to assess the incidence and the trend of each hematologic malignancy and to evaluate the difference between Japan and US. The diseases evaluated in this study were acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), chronic myelogenous leukemia (CML), multiple myeloma (MM), Hodgkin lymphoma (HL), and non-Hodgkin lymphoma (NHL). Methods: To evaluate the incidence of hematologic malignancies, we used population-based registry data in Japan and the United States (US). The population-based cancer registry of Japan included 100,637 cases and the data in the US, SEER included 172,925 cases. The period covered in this analysis is 1993-2006 in Japan and 1993-2008 in the US. Rates of sex-specific, age-standardized incidence with 95% confidence intervals were estimated and standardized by age-adjustment according to the world standard population. We also estimated the annual percent change using joinpoint regression analysis and evaluated the significance of the trend. Results: The overall age-standardized incidence rate of all hematologic malignancies per 100,000 in 2006 was 14.9 for males and 10.0 for females in Japan, 33.4 for males and 24.3 for females in the US. The difference in the incidence between Japan and US is impressive for HL, NHL and MM (approximately 3-10 fold), whereas AML, ALL, and CML have a similar incidence. The total number of hematologic malignancies was found to be increasing significantly in Japan whereas no obvious change was seen in the US {annual percent change (95%CI) Japan; +1.5% (0.9 to 2.1), US; +0.1% (-0.1 to 0.2)}. As for details, AML and the lymphoid malignancies (HL and NHL) are increasing significantly in Japan whereas there has been a marginal change in the US. Interestingly, the incidence of CML has been decreasing during this period in both Japan and the US, whereas no obvious change was seen in MM in their country. Conclusion: In conclusion, we showed the difference in the incidence of hematologic malignancies between Japan and the US. The incidence of hematologic malignancies is lower in Japan than the US, but is increasing significantly. The improvement in the quality of cancer registry systems and the organization of these registries between countries enables us to unite the data worldwide that will bring us new insights.
Citation Format: Dai Chihara, Lidsay Morton, Hidemi Ito, Tomohiro Matsuda, Akiko Shibata, Tomotaka Sobue, Denis D. Weisenburger, Keitaro Matsuo. The difference in the incidence and the trend of hematologic malignancies in Japan and the United States. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2535. doi:10.1158/1538-7445.AM2013-2535