Racial and gender disparities in the incidence of anal cancer: Analysis of the Nationwide Inpatient Sample (NIS)

Background: Racial and gender disparities have been shown in other gastrointestinal cancers. However, there is a paucity of data on racial and gender disparities in anal cancer (AC). The aim of this study was to assess racial and gender disparities among patients with AC. Methods: We analyzed data from the National Inpatient Sample (NIS) 2011 database of patients diagnosed with AC with age ≥18. Demographic data including age, race and gender were assessed. Patients were stratified based on race and gender. Log binomial regression was used to generate risk ratios. Results: A total of 6,013,105 patients were assessed and 1,956 (0.03%) patients had AC. Female patients were more at risk of developing AC [relative risk (RR): 1.14, P=0.02]. Whites and Blacks had the highest incidence followed by Asians/Pacific Islanders. Black males had increased risk of AC (RR: 1.43, P<0.01). Amongst Hispanics; both males (RR: 0.69, P=0.05) and females (RR: 0.46, P<0.0001) had decreased risk of developing AC. Finally, we saw that Asian females had a much lower risk of developing AC (RR: 0.33, P<0.01). Conclusions: Racial disparities and gender differences exist in the incidence of AC. Potential causes for this disparity are disparate access to healthcare, lack of education, and lack of awareness. Greater understanding of the racial disparity in AC can help identify at risk population and eventually lead to improved preventative measures to ultimately reduce the incidence of AC.