Cancer risks for relatives of patients with serrated polyposis

Win AK, Walters RJ, Buchanan DD, Jenkins MA, Sweet K, Frankel WL, de la Chapelle A, McKeone DM, Walsh MD, Clendenning M, Pearson SA, Pavluk E, Nagler B, Hopper JL, Gattas MR, Goldblatt J, George J, Suthers GK, Phillips KD, Woodall S, Arnold J, Tucker K, Field M, Greening S, Gallinger S, Aronson M, Perrier R, Woods MO, Green JS, Walker N, Rosty C, Parry S, Young JP (2012) Cancer risks for relatives of patients with serrated polyposis. The American journal of gastroenterology 107:770-778

OBJECTIVES: Serrated polyposis (hyperplastic polyposis) is characterized by multiple polyps with serrated architecture in the colorectum. Although patients with serrated polyposis are known to be at increased risk of colorectal cancer (CRC) and possibly extracolonic cancers, cancer risk for their relatives has not been widely explored. The aim of this study was to estimate the risks of CRC and extracolonic cancers for relatives of patients with serrated polyposis. METHODS: A cohort of the 1,639 first- and second-degree relatives of 100 index patients with serrated polyposis recruited regardless of a family history of polyps or cancer from genetic clinics in Australia, New Zealand, Canada, and the USA, were retrospectively analyzed to estimate the country-, age-, and sex-specific standardized incidence ratios (SIRs) for relatives compared with the general population. RESULTS: A total of 102 CRCs were observed in first- and second-relatives (SIR 2.25, 95% confidence interval (CI) 1.75-2.93; P<0.001), with="" 54="" in="" first-degree="" relatives="" (sir="" 5.16,="" 95%="" ci="" 3.70-7.30;=""><0.001) and="" 48="" in="" second-degree="" relatives="" (sir="" 1.38,="" 95%="" ci="" 1.01-1.91;="" p="0.04)." six="" pancreatic="" cancers="" were="" observed="" in="" first-degree="" relatives="" (sir="" 3.64,="" 95%="" ci="" 1.70-9.21;="" p="0.003)." there="" was="" no="" statistical="" evidence="" of="" increased="" risk="" for="" cancer="" of="" the="" stomach,="" brain,="" breast,="" or="" prostate.="" conclusions:="" our="" finding="" that="" relatives="" of="" serrated="" polyposis="" patients="" are="" at="" significantly="" increased="" risk="" of="" colorectal="" and="" pancreatic="" cancer="" adds="" to="" the="" accumulating="" evidence="" that="" serrated="" polyposis="" has="" an="" inherited="">