OBJECTIVES : The incidence and mortality of early-onset (<50 years of age) colorectal cancer (EOCRC) in comparison to colorectal cancer in patients greater than 50 years of age is steadily rising. Due to a delay in screening, younger populations are susceptible to later staged diagnoses, more aggressive treatment strategies, adverse histologic features, and increased mortality. This study summarizes the evidence on early-onset CRC screening, diagnosis, treatment, and survival in the United States

METHODS : MEDLINE, the Cochrane Library, and Google Scholar were searched for English language publications describing studies on early-onset CRC. A study was eligible for inclusion if it reported information on CRC or EOCRC incidence, screening, survival, risk factors, pathophysiology, clinical characteristics, genetic features, diagnostic criteria, treatment strategy or evaluation, racial, geographic, and socioeconomic disparities, and was published in English between January 2000 and October 2020.

RESULTS : Patients diagnosed with EOCRC tend to have a distinct histological type including poorly differentiated tumors and signet cells, making diagnosis and treatment more difficult. Genetic features such as hereditary syndromes can contribute to EOCRC, but do not account for the majority of cases. Over-treatment patterns of young adults with EOCRC were observed. EOCRC patients that were over-treated were not shown to have greater survival rates. Ethnic minorities and low socioeconomic classes, especially African-Americans (AA), had greater mortality rates and under-treatment patterns.

CONCLUSIONS : EOCRC incidence and mortality rates are rising rapidly, and many young adults are not being treated appropriately. Young patients have a greater likelihood of being over-treated and/or misdiagnosed, leading to long-term toxicity effects and decreased quality of life. Special attention needs to be addressed to young AA adults, to counter the observed trend, as they have the highest incidence of CRC among young population groups by race/ethnicity.