Colorectal neoplasia is not uncommon in siblings aged under 50 years of patients with early-onset colorectal advanced adenomas: A cross-sectional study

Research on the prevalence of adenomas and colorectal cancer (CRC) in individuals aged 50 years or younger with first-degree relatives diagnosed with early-onset colorectal advanced adenoma (E-CAA), defined as the onset of colorectal advanced adenoma (CAA) at or before 50 years of age, is scarce. We examined the prevalence of colorectal neoplasia among siblings aged 50 years or younger of E-CAA patients. A cross-sectional study was conducted at the University Medical Center in Ho Chi Minh City, Vietnam. Study participants included 96 siblings aged 50 years or younger from 58 E-CAA patients, who were selected from a total of 732 identified siblings, with a notably high rate of participation refusal. All included siblings were either older than the patients diagnosed with E-CAA or younger by no more than10 years. Individuals with a family history of CRC were excluded from this study. All siblings underwent standard bowel preparation and colonoscopies. The mean age of siblings was 40.9 ± 6.0 years, with males comprising 47.9%. Most of the siblings (83.3%) were asymptomatic. The prevalence of colorectal neoplasia among the siblings was 25%. Of these, 95.8% were adenomas, and CRC was identified in one sibling. The proportion of CAA and advanced colorectal neoplasia was 6.3% and 7.3%, respectively. These proportions increased to 13% and 15.2%, respectively, among the male siblings. None of the female siblings were diagnosed with CAA or advanced colorectal neoplasia. No statistically significant difference was observed in the prevalence of colorectal neoplasia (23.7% vs 25.9%, P = .81), CAA (5.3% vs 6.9%, P > .99), or advanced colorectal neoplasia (7.9% vs 6.9%, P > .99) between sibling age groups (40 years or 40-50 years). Colorectal neoplasia is not uncommon in siblings aged ≤ 50 years of E-CAA patients. The prevalence of CAA and advanced colorectal neoplasia is markedly elevated in male siblings. These high-risk individuals may benefit from early targeted colorectal cancer screening.