title: The clinical features of rectal cancers with high-frequency microsatellite instability (MSI-H) in Japanese males.
abstract: Colorectal cancers with high-frequency microsatellite instability (MSI-H) are known to display striking differences in their clinical and pathological features compared to microsatellite stable (MSS) cancers. Previous studies revealed that MSI-H cancers are more likely to occur in women, irrespective of the higher incidence of colorectal cancer in men. In this study we investigated the gender-specific clinico-pathological features of MSI positive colorectal cancer in Japanese individuals. A series of 478 colorectal carcinomas were collected in an unbiased manner and analyzed for microsatellite instability status. Seven percent, 6% and 87% of tumors showed MSI-H, low-frequency microsatellite instability (MSI-L) and MSS, respectively. A comparison of gender indicated a statistical significance in terms of the distribution of the subsite and age of onset of MSI-H colorectal cancer. In general, MSI-H cancers prone to develop in the proximal colon however, we found that about 36% of MSI-H cancers in men developed in the rectum. These rectal cancers were more likely to have a mucinous component and multiple colorectal cancers including critical lesion. These findings should be useful to find MSI positive rectum cancer.
authors.affiliation: Laboratory of Cancer Genetic Diagnosis, Saitama Cancer Center, 818 Komuro Ina, Kitaadachigun, Saitama 362-0806, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Ishikubo
authors.forename: Yoji
authors.initials: Y
authors.lastname: Nishimura
authors.forename: Kensei
authors.initials: K
authors.lastname: Yamaguchi
authors.forename: Udompun
authors.initials: U
authors.lastname: Khansuwan
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Arai
authors.forename: Terutada
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Ohkura
authors.forename: Yojiro
authors.initials: Y
authors.lastname: Hashiguchi
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Kiwamu
authors.initials: K
authors.lastname: Akagi
mesh_terms: D017668:Age of Onset; D000368:Aged; D002277:Carcinoma / Q000235:genetics* / Q000473:pathology; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D018895:Microsatellite Repeats; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012004:Rectal Neoplasms / Q000235:genetics* / Q000473:pathology; D012737:Sex Factors