Rjs. Thomas et al., FREQUENCY AND CLINICOPATHOLOGICAL ASSOCIATIONS OF RAS MUTATIONS IN COLORECTAL-CANCER IN THE VICTORIAN POPULATION, Australian and New Zealand journal of surgery, 67(5), 1997, pp. 233-238
Background: Mutations in the oncogene ras occur in 20-50% of colorecta
l cancers. The presence of these mutations allows screening tests to b
e developed based on the identification of mutant DNA in cells derived
from cancers. A study of the prevalence and clinicopathological assoc
iations of ras mutations was undertaken. Methods: The frequency of mut
ations in codons 12 and 13 of the K-ras gene was investigated in 103 c
olorectal carcinomas using restriction fragment length polymorphism. R
esults: Mutations were detected in 32% (33/103) of the tumours, predom
inantly in codon 12 (25/33). No mutations were detected in normal-appe
aring mucosa from the same patients. Conclusions: Analysis of the freq
uency of ras mutations compared with various independent clinical vari
ables revealed a sex-linked relationship between the presence of a ras
mutation and nodal status but no correlation with any other clinical
parameter was found. The findings suggest that screening tests based o
n ms mutation detection may lack sensitivity because of the presence o
f mutations in only 32% of tumours.