Mortality Predictions for Men and Women Diagnosed with Anal Canal Squamous Cell Carcinoma in the United States

Abstract

Objective: Studies have concluded that treatments for patients with anal cancer vary based on their age, sex, and race. We examined gender-specific differences in mortality and overall survival for patients with squamous cell carcinoma (SCC) of the anal canal (AC), based on differences in treatment, stage and demographic factors. Method: SEERs retrospective cohort dataset was used to review all patients diagnosed with SCC of the AC between 2000 and 2018. We analyzed survival by sub-distributed Cox models and estimated overall survival probabilities through nomograms based on cancer treatments, tumor characteristics, and demographic data Results: In the study, 24,892 patients with SCC in the AC had a median survival time of 43 months (IQR: 16-97). However, males (median 38.0 months, IQR: 13.0-92.0) had significantly shorter median survival times than females (median 46.0 months, IQR: 17-100). There were 12% of patients in metastatic stages, with females (70.3%) receiving more treatments than males (29.7%). The survival rate of patients with SCC of the AC who underwent radiation treatment was significantly higher (HR 0.72, 95% CI: 0.65-0.80, p<0.001). Moreover, compared to those without surgery on the primary site, those undergoing surgery on the primary site had a 49% lower mortality rate (HR 0.51; 95% CI: 0.45 to 0.56, p0.001). According to the study, the overall survival probability at 5 and 10 years for patients who received chemotherapy on primary sites was about 90%, compared to only 40% and 22% for those who did not receive chemotherapy. Surgical intervention yielded similar results, but radiation therapy did not significantly improve survival rates. Conclusion: Compared with men, women with SCC of the AC have a higher survival rate, and younger patients tend to live longer. The factors negatively affecting survival were increasing age, non-whites, divorced / separated / widowed, and advanced stages of cancer. A significant increase in survival was seen after surgery and chemotherapy for SCC, while radiation had little effect on survival.