Geographic Disparities in Socioeconomic Factors and Advanced-stage Presentation in Rectosigmoid Cancer: A National Cancer Database Analysis

Background/Aim: Rectosigmoid cancer is a clinically distinct subset of colorectal malignancy, yet geographic variation in its demographic and socioeconomic profile across U.S. regions remains poorly characterized. Understanding regional disparities in patient composition and stage at diagnosis is essential for guiding targeted public health strategies. This study examined geographic variation in demographic, socioeconomic, and clinical characteristics among U.S. patients with rectosigmoid cancer. Patients and Methods: Using the National Cancer Database (NCDB), we conducted a cross-sectional analysis of patients diagnosed with rectosigmoid cancer between 2004 and 2020. Patients were assigned to one of six U.S. geographic regions based on reporting facility location. Descriptive analyses were performed to evaluate age, sex, race and ethnicity, insurance type, income, urban-rural residence, and American Joint Committee on Cancer (AJCC) stage at diagnosis. Results: Among 1,044,912 patients (mean age, 65.0 years; 55.9% male), substantial racial and socioeconomic variation was identified across regions. Black patients were most prevalent in the Southeast (15.6%) and least represented in the Mountain region (1.8%). Asian patients were highest in the Pacific region (16.2%). Uninsured rates were highest in the Southwest (6.9%) and Southeast (4.5%). Advanced-stage (III-IV) disease at diagnosis was most common in the Southwest (52.9%) and least common in the Northeast (47.4%). Conclusion: Substantial geographic variation exists in the demographic and socioeconomic profile of patients with rectosigmoid cancer, corresponding to meaningful differences in stage at diagnosis. These disparities likely reflect structural inequities in screening access, insurance coverage, and healthcare infrastructure. Region-specific interventions, including Medicaid expansion, mobile screening programs, and targeted patient navigation, are warranted to improve outcomes nationwide.