Pathology

 in gastric carcinoma
 in colonic carcinoma

Defects in the mismatch repair (MMR) genes hMLH1 and hMSH2 have been found in 10% to 20% of sporadic colorectal carcinomas and also many cases of hereditary nonpolyposis colorectal cancer syndrome. Patients with these tumors have an improved prognosis and may show greater sensitivity to chemotherapy.

Mucinous tumors were common in hMLH1 tumors (36.3%) but not in hMSH2 tumors (11.1%). hMLH1 tumors were most likely to be poorly differentiated (70%), which was uncommon with hMSH2 tumors (22.2%). hMSH2 tumors were more likely to be confined to the wall (66.7%) than hMLH1 (20%) or intact tumors (23%). (#14576472#)

References

 Kruse R, Ruzicka T. DNA mismatch repair and the significance of a sebaceous skin tumor for visceral cancer prevention. Trends Mol Med. 2004 Mar;10(3):136-41. PMID: #15102357#

 Wei K, Kucherlapati R, Edelmann W. Mouse models for human DNA mismatch-repair gene defects. Trends Mol Med. 2002 Jul;8(7):346-53. PMID: #12114115#

 Peltomaki P. Deficient DNA mismatch repair: a common etiologic factor for colon cancer. Hum Mol Genet. 2001 Apr;10(7):735-40. PMID: #11257106#

 Simpson AJ, Caballero OL, Pena SD. Microsatellite instability as a tool for the classification of gastric cancer. Trends Mol Med. 2001 Feb;7(2):76-80. PMID: #11286759#

 Eshleman JR, Markowitz SD. Mismatch repair defects in human carcinogenesis. Hum Mol Genet. 1996;5 Spec No:1489-94. PMID: #8875255#