Colonic cancer in a 34-yr-old woman: should it prompt microsatellite instability studies and mismatch repair gene testing?

Abstract

It remains debatable whether young patients with colorectal tumors should undergo genetic testing with the aim of identifying new hereditary nonpolyposis colorectal cancer families. We describe a case of a young woman with colon cancer with no clinical criteria of hereditary nonpolyposis colorectal cancer, whose genetic analysis showed that the tumor displayed microsatellite instability, and in whom a truncated protein in hMSH2 gene was found, which was also present in two at-risk relatives.