Familial colorectal cancer risk in half siblings and siblings: nationwide cohort study

Objective To explore the risk of colorectal cancer in family members of patients with colorectal cancer, with an emphasis on subtypes of second degree relatives, especially half siblings, which were lacking in the literature. Design Ambidirectional cohort study. Setting Nationwide Swedish Family Cancer Data (record linkage). Participants All people residing in Sweden and born after 1931, with their biological parents, totalling >16 million...