{Reference Type}: Journal Article
{Title}: Colorectal cancer and advanced adenoma characteristics according to causative mismatch repair gene variant in Japanese colorectal surveillance for Lynch syndrome.
{Author}: Chino A;Tanakaya K;Nakajima T;Akagi K;Takao A;Yamada M;Ishida H;Komori K;Sasaki K;Miguchi M;Hirata K;Sudo T;Miyakura Y;Ishikawa T;Yamaguchi T;Tomita N;Ajioka Y;
{Journal}: J Gastroenterol
{Volume}: 59
{Issue}: 8
{Year}: 2024 Aug 21
{Factor}: 6.772
{DOI}: 10.1007/s00535-024-02128-5
{Abstract}: BACKGROUND: The optimal interval of colonoscopy (CS) surveillance in cases with Lynch syndrome (LS), and stratification according to the causative mismatch repair gene mutation, has received much attention. To verify a feasible and effective CS surveillance strategy, we investigated the colorectal cancer (CRC) incidence at different intervals and the characteristics of precancerous colorectal lesions of LS cases.
METHODS: This retrospective multicenter study was conducted in Japan. CRCs and advanced adenomas (AAs) in 316 LS cases with germline pathogenic variants (path_) were analyzed according to the data of 1,756 registered CS.
RESULTS: The mean time interval for advanced CRCs (ACs) detected via CS surveillance was 28.7 months (95% confidence interval: 13.8-43.5). The rate of AC detection within (2.1%) and beyond 2 years (8.7%) differed significantly (p = 0.0003). AAs accounted for 43%, 46%, and 41% of lesions < 10 mm in size in the MLH1-, MSH2-, and MSH6-groups, respectively. The lifetime incidence of metachronous CRCs requiring intestinal resection for path_MLH1, path_MSH2, and path_MSH6 cases was 34%, 23%, and 14% in these cases, respectively. The cumulative CRC incidence showed a trend towards a 10-year delay for path_MSH6 cases as compared with that for path_MLH1 and path_MSH2 cases.
CONCLUSIONS: In cases with path_MLH1, path_MSH2, and path_MSH6, maintaining an appropriate CS surveillance interval of within 2 years is advisable to detect of the colorectal lesion amenable to endoscopic treatment. path_MSH6 cases could be stratified with path_MLH1 and MSH2 cases in terms of risk of metachronous CRC and age of onset.