The Rising Trend of Metastatic Colorectal Cancer: A Hospital-Based Study across Age Groups

Purpose: Metastatic colorectal cancer (mCRC) is a major contributor to cancer-related morbidity and mortality in the United States. Although colorectal cancer has traditionally affected older adults, emerging data suggest shifts in age-specific disease patterns. The purpose of this study was to evaluate age-stratified proportion of hospitalizations and temporal trends in hospitalizations for metastatic colorectal cancer using a nationally representative inpatient database to identify populations potentially underserved by current screening guidelines. Methods: A retrospective analysis of the National Inpatient Sample (NIS) from 2016 to 2019 was conducted. Hospitalizations with a diagnosis of mCRC were identified using ICD-10 codes. Patients were categorized into five age groups: ≤45, 46 - 55, 56 - 65, 66 - 75, 76 - 85, and ≥86 years. Descriptive statistics summarized proportion of hospitalizations, analysis of variance compared annual differences, and linear regression assessed temporal trends. Statistical significance was defined as p < 0.05. Results: A total of 426,025 hospitalizations were identified. Patients aged 66 - 75 years accounted for 73,070 cases and demonstrated a significant increase in proportion of hospitalizations from 24.62% in 2016 to 26.54% in 2019 (p < 0.05). Individuals aged ≤45 years and ≥76 years comprised approximately 29% of hospitalizations. Conclusion: Hospitalizations for metastatic colorectal cancer are increasing among adults aged 66 - 75 years, with a substantial burden also observed at age extremes. These findings suggest potential gaps in current screening strategies. These findings highlight age-specific disparities in hospitalization burden that may inform future screening and health system planning.