251 Racial Differences in the Incidence, Clinicopathological Features and Survival of Patients With Noncardia Gastric Adenocarcinoma - Results From a Large Integrated Healthcare Organization

Abstract

BACKGROUND: Despite recent advances in screening and treatment for HCC, racial disparities in incidence and mortality continue to exist. In United States, blacks are reported to have high HCC incidence, advanced tumor stage at diagnosis, lower rates of curative therapies and higher mortality rates. In contrast, Asians are known to have high incidence of HCC compared to non-Asians; however, prior studies have also shown better survival rates in Asians compared to non-Asians. The purpose of the study is to determine if racial disparities persist in post-MELD exception era and to identify the determinants of survival. METHODS: We used information on patients diagnosed with HCC from 18 registries in the Surveillance, Epidemiology and End Results (SEER) database comprising 28% of the US population between 2004 and 2007 to calculate relative survival rates for 5 years after diagnosis. For the analysis of survival impact, we selected a uniform patient cohort comprising of cases that fall within the Milan criteria consisting of absence of extra-hepatic disease and vascular invasion, with single lesions ,5 cm or no more than 3 lesions of , 3 cm in largest diameter. Survival rates were calculated for the entire group as well as for subgroups based on age, gender, race/ethnicity (cohort was stratified into white, black or other or Asian vs. NonAsian). Kaplan-Meier survival curves were compared using log rank test. Statistical analysis was done using SEER*Stat software 8.0.1 and SPSS 20.0. RESULTS: Between 2004 and 2007, 2068 patients with HCC tumors meeting Milan criteria were identified and included in the current analysis. A total of 45% of these patients received only supportive therapy with the remaining undergoing partial hepatectomy (12%), liver-directed palliative therapy (23%), or liver transplantation (20%). Blacks had significantly poorer 5-year survival rates compared to whites, whereas Asians had better 5-year survival rates compared to non-Asians across most treatment groups except for liver transplantation where no significant differences were found between Asians vs. non-Asians (Figure). Multivariate Cox proportional hazards analysis showed older age, black race and non-Asian ethnicity to be independent predictors for poor survival rates. CONCLUSIONS: Results of SEER analysis shows that survival rates are still poor in blacks compared to whites in post-MELD exception era and survival rates in Asians continue to be better than non-Asians. Both biological-clinical and healthcare access factors should be studied to improve the currently observed disparity between black and non-black patients with HCC. In Asians, though with higher HCC incidence rates, survival rates are better compared to non-Asians. Closer examination of this cohort may elucidate genetic and/or environmental factors responsible for improved outcomes.