Genetically transmitted predisposition to develop
Cancer Family Syndrome; Familial Cancer Syndrome;
Hereditary Nonpolyposis Colorectal Cancer (HNPCC); Hereditary Nonpolyposis
First described by Alder Scott Warthin, an American
pathologist, in 1913.
Five percent of the colorectal cancer population.
Both clinical forms of HNPCC are autosomal
dominant with a penetrance of 85 to 90%. Two DNA mismatch repair genes
are closely linked to the disease: hMSH2 gene in chromosome 2p and hMLS1
gene in chromosome 3p. Mutations in these genes account for 90% of all
known HNPCC families.
Defective DNA mismatch repair leads to
accumulation of mutations. The mutation load can be identified as errors in
long tandem repeat sequences, which produce microsatellite instability.
Familial history, colonic screening examinations, DNA
Two clinical forms described:
- Lynch Syndrome I: Familial predisposition to early-onset colorectal cancer (mainly right
- Lynch Syndrome II: Same features and familial predisposition with an associated predisposition
for other primary cancers (often female reproductive organs, particularly
endometrial carcinoma). This variant is not easily recognized because of the
lack of phenotypical expression as familiar adenomatous polyposis.
All precautions before anesthesia
will be dictated by those associated with the patient's underlying medical condition.
Anesthetic considerations are those
associated with the surgical procedure only or any associated medical
No specific pharmacological
implications except for patients receiving chemotherapy.
de Vos tot Nederveen Cappel WH, Nagengast FM, Griffioen G, et al:
Surveillance for hereditary nonpolyposis colorectal cancer: A long-term
study on 114 families. Dis Colon Rectum 45:1588, 2002.
Mitchell RJ, Farrington SM, Dunlop MG, et al: Mismatch repair genes hMLH1
and hMSH2 and colorectal cancer: A HuGE review. Am J Epidemiol
Wagner A, Tops C, Wijnen JT, et al: Genetic testing in hereditary
non-polyposis colorectal cancer families with a MSH2, MLH1, or MSH6
mutation. J Med Genet