Colon Cancer Flashcards
What is an aberrant crypt focus?
if there is self-limited hyperproliferation in a colonic crypt –> but can expand to the surface and lead to a polyp
What is the most common trigger of a hyperproliferative epithelium?
5p mutation or loss of APC
What is the most common trigger that turns hyperproliferative epithelium into early and then intermediate and then late adenoma?
DNA hypomethylation –> kras mutation to be constitutively active for proliferation –> loss of DCC
What is the most common trigger that turns colonic adenoma into cancer ?
p53
What prostaglandin producer is increased in many polyps?
Cox 2
Are obesity, smoking, and alcohol risk factors for CRC?
no
Gardener’s Syndrome
FAP + extraintestinal lesions like osteomas, desmoid tumors, supernumerary teeth, soft tissue tumors, etc.
In what condition are duodenal polyps a common finding?
FAP –> hard to resect duodenal polyps
With what gene region is classic FAP associated?
throughout
With what gene region is attenuated FAP associated?
3’ and 5’ end
With what gene region is CHRPE associated?
exon 9 or prior –> eye changes
Most common inherited CRC?
Lynch syndrome/HNPCC
Features of Lynch Syndrome
early but variable age at dx –> tumor site in proximal colon + extracolonic cancers
Underlying feature of lynch syndrome
microsatellite instability
Managing CRC
genetic testing, colon resection
