Clinicopathologic and genetic features of young patients with colorectal cancer

Abstract

On average, patients with CMMR-D presented younger, with a mean age of 14 years old at diagnosis. 65.2% of patients with LS presented with a proximal tumour (65.2%) compared with the polyposis (10.2%) and NOS (34.4%) groups. In contrast, 83% of polyposis patients and 65.5% of NOS patients presented with distal colon or rectal cancers. Family history was significant for the majority of LS patients with 54 of 73 (74%) meeting Amsterdam I or II criteria. Two of the 7 patients with IBD, and 15 of 98 NOS patients also met Amsterdam I/II criteria, as opposed to the CMMR-D families where none met these criteria. Six LS patients presented with sporadic CRC, as did approximately 25% of polyposis patients and 59.2% of the NOS patients. Conclusions Cancer site differs between individuals ≤35 years with LS, polyposis and NOS CRC. Greater than 1/3 of patients presented with no significant family history of CRC. While the majority of patients diagnosed with CRC ≤35 have a known hereditary CRC syndrome or risk predisposition, 69 of 221 (31.2%) of individuals appear to have no recognizable syndrome.