Abstract 4253: Anal cancer survivorship: Clinical and nonclinical factors
Authors: Boakye Eric Adjei , Simpson Matthew , Rohde Rebecca , Anderson Lauren , Tobo Betelihem B. , Burroughs Thomas E. , Osazuwa-Peters Nosayaba 
Published: August 2018

Purpose: An estimated 8,200 cases of anal cancer will be diagnosed in 2017, accounting for nearly 1,100 deaths. Though anal cancer is a relatively rare malignancy, its increasing incidence has coincided with the increase in prevalence of risky sexual practices associated with anal human papillomavirus (HPV) infection, especially among men. At least 9 in 10 anal cancers are associated with HPV. Due to the rarity of anal cancer, little is known about factors affecting survivorship of anal cancer patients. The aim of this study was to evaluate clinical and nonclinical factors associated with anal squamous cell carcinoma (ASCC) survival in the United States.

Methods: A retrospective cohort study of patients aged ≥18 years with ASCC in the National Cancer Institute Surveillance, Epidemiology, and End Results registry (2004-2014) was analyzed. ASCC (site codes C21.0-C21.9 and C20.9), were coded for invasive squamous cell carcinomas per the International Classification of Diseases for Oncology, third edition. The outcome was survival (alive or dead) and the exposures were clinical (stage of presentation and treatment modality), and nonclinical (marital status, age, sex, race/ethnicity). Fine and Gray proportional hazards regression model were used to assess differences in survival among sociodemographic and clinical factors.

Results: There were 13,142 patients diagnosed with ASCC between 2004 and 2014. Mortality rate during the study period was 34.9% and median survival time was 113 months. In the adjusted model, a one-year increase in age was associated with 2% increased risk of death (adjusted hazard ratio (aHR) =1.02; 95% confidence interval (CI): 1.02-1.03). Compared with female patients, male patients (aHR=1.54; 95% CI: 1.40-1.70) had higher hazard of death, as did patients who were non-Hispanic black (aHR=1.40; 95% CI: 1.23-1.60) or non-Hispanic other (aHR=1.34; 95% CI: 1.09-1.65) versus non-Hispanic white. Patients who were never married (aHR=1.29; 95% CI: 1.15-1.44) or widowed (aHR=1.37; 95% CI: 1.18-1.59) had higher hazard of death compared to married patients. Patients had higher hazard of death if they were had stage II (aHR=2.01; 95% CI: 1.62-2.49), stage III (aHR=4.58; 95% CI: 3.70-5.67) or stage IV cancer (aHR=13.43; 95% CI: 10.74-16.78); and had not received surgery (aHR=1.41; 95% CI: 1.26-1.57).

Conclusion: Besides the clinical factors known to impact survival, including stage and treatment modality, several nonclinical factors are associated with the survival of anal cancer in the United States: age, sex, race/ethnicity, and marital status. It is important that interventions considering these factors are developed to improve survivorship, especially among the unmarried, males, and minority patients.

Citation Format: Eric Adjei Boakye, Matthew Simpson, Rebecca Rohde, Lauren Anderson, Betelihem B. Tobo, Thomas E. Burroughs, Nosayaba Osazuwa-Peters. Anal cancer survivorship: Clinical and nonclinical factors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4253.