Increased morbidity and mortality of hepatocellular carcinoma patients in lower cost of living areas

BACKGROUND: The incidence and mortality rates of hepatocellular carcinoma (HCC) are increasing in the United States. However, the increases in different racial and socioeconomic groups have not been homogeneous. Access to healthcare based on socioeconomic status and cost of living index (COLI), especially in HCC management, is under characterized. AIM: The aim was to investigate the relationship between the COLI and tumor characteristics, treatment modalities, and survival of HCC patients in the United States. METHODS: A retrospective study of the Surveillance, Epidemiology, and End Results (SEER) database was conducted to identify patients with HCC between 2007 and 2015 using site code C22.0 and the International Classification of Disease for Oncology, 3rd edition (ICD-O-3) codes 8170-8173, and 8175. Cases of fibrolamellar HCC were excluded. Variables collected included demographics, COLI, insurance status, marital status, stage, treatment, tumor size, and survival data. Interquartile ranges for COLI were obtained. Based on the COLI, the study population was separated into four groups: COLI ≤ 901, 902-1044, 1045-1169, ≥ 1070. The χ(2) test was used to compare categorical variables, and the Kruskal-Wallis test was used to compare continuous variables without normal distributions. Survival was estimated by the Kaplan-Meier method. We defined P < 0.05 as statistically significant. RESULTS: We identified 47,894 patients with HCC. Patients from the highest COLI areas were older (63 vs 61 years of age), more likely to be married (52.8% vs 48.0%), female (23.7% vs 21.1%), and of Asian and Pacific Islander descent (32.7% vs 4.8%). The patients were more likely to have stage I disease (34.2% vs 32.6%), tumor size ≤ 30 mm (27.1% vs 23.1%), received locoregional therapy (11.5% vs 6.1%), and undergone surgical resection (10.7% vs 7.0%) when compared with the lowest quartile. The majority of patients with higher COLIs resided in California, Connecticut, Hawaii, and New Jersey. Patients with lower COLIs were more likely to be uninsured (5.7% vs 3.4%), have stage IV disease (15.2% vs 13%), and have received a liver transplant (6.6% vs 4.4%) compared with patients from with the highest COLI. Median survival increased with COLI from 8 (95%CI: 7-8), to 10 (10-11), 11 (11-12), and 14 (14-15) mo (P < 0.001) among patients with COLIs of ≤ 901, 902-1044, 1045-1169, ≥ 1070, respectively. After stratifying by year, a survival trend was present: 2007-2009, 2010-2012, and 2013-2015. CONCLUSION: Our study suggested that there were racial and socioeconomic disparities in HCC. Patients from lower COLI groups presented with more advanced disease, and increasing COLI was associated with improved median survival. Future studies should examine this further and explore ways to mitigate the differences.