Prevalence of MLH1/MSH2 mutations in CRC families was significantly increased by the presence of: (i) fulfilled Amsterdam criteria; (ii) four or more CRCs; or (iii) one or more endometrial cancer.
We sequenced the MLH1/MSH2 coding and promoter core regions in CRC patients diagnosed below age 40, and/or with multiple primary cancers or familial cancer clustering suggestive of HNPCC, and correlated deleterious mutations with clinical and tumour features.
These results indicate that there are different oncogenic pathways in the MSI sporadic colorectal cancers with germline missense mutations in the hMSH2 gene.
Tumour samples from 73 CRC patients who were treated in advanced stage with either irinotecan alone or in combination with 5-FU/leucovorin, were analysed for expression of Bcl-2, hMLH1 and hMSH2 using immunohistochemistry.