Talk:Colon Histology 2009
Background
- "Now have a closer look at the components of the wall of the colon. Villi are absent and the crypts appear deeper than the ones you observed in the small intestine. Goblet cells are numerous. The lamina propria and muscularis mucosae may be difficult to distinguish. Note also that a thin layer of longitudinal muscle is found between the taenia coli on the outside of the inner circular muscle layer."
- "Several genes contributing to a susceptibility to two types of colon cancer:
FAP (familial adenomatous polyposis) So far, only one FAP gene has been discovered - the APC gene on chromosome 5. But over 300 different mutations of that gene have been identified. Individuals with this syndrome develop many polyps in their colon. People who inherit mutations in this gene have a nearly 100 percent chance of developing colon cancer by age 40.
HNPCC (hereditary nonpolyposis colorectal cancer) Individuals with an HNPCC gene mutation have an estimated 80 percent lifetime risk of developing colon or rectal cancer. However, these cancers account for only three to five percent of all colorectal cancers. So far, four HNPCC genes have been discovered:
hMSH2 on chromosome 2, which accounts for 60 percent of HNPCC colon cancer cases. hMLH1 on chromosome 3, which accounts for 30 percent of HNPCC colon cancer cases. hPMSI on chromosome 2, which accounts for 5 percent of HNPCC colon cancer cases. hPMS2 on chromosome 7, which accounts for 5 percent of HNPCC colon cancer cases. Together, FAP and HNPCC gene mutations account for approximately 5 percent of all colorectal cancers. These hereditary cancers typically occur at an earlier age than sporadic (non-inherited) cases of colon cancer. The risk of inheriting these mutated genes from an affected parent is 50 percent for both males and females. The genes that cause these two syndromes were relatively easy to discover because they exert strong effects. Other genes that cause susceptibility to colon cancer are harder to discover because the cancers are caused by an interplay among a number of genes, which individually exert a weak effect."
- http://jcb.rupress.org/cgi/content/full/168/4/633/FIG6
- colon hemangiomas are rare, benign vascular lesions, with patients usually presenting with repetitive painless bleeding from the rectum http://www.ncbi.nlm.nih.gov:80/pmc/articles/PMC2769130/?tool=pmcentrez
- Fecal Occult Blood Screening Does Reduce Death From Colon Cancer George D. Lundberg Medscape J Med. 2008; 10(10): 244. Published online 2008 October 23. PMCID: PMC2605150
- Survival from cancers of the colon and rectum in England and Wales up to 2001 A G Acheson and J H Scholefield Br J Cancer. 2008 September 23; 99(S1): S33–S34. Published online 2008 September 23. doi: 10.1038/sj.bjc.6604580. PMCID: PMC2557538
--Mark Hill 10:50, 1 November 2009 (EST) This page was last modified on October 30, 2009, at 17:22. This page has been accessed 65 times.
