ABSTRACT
GOALS: This study sought to clarify sex differences in KRAS mutations and clinical predictors of KRAS 13 codon mutations. BACKGROUND: Sex differences in KRAS mutations and predictors for KRAS codon 13 mutations in colorectal cancer (CRC) are unclear. STUDY: Between October 2007 and May 2016, 328 patients underwent surgery for CRCs that were analyzed for KRAS mutations at a referral university hospital. Sex differences in the rates and distributions of KRAS mutations, and factors predictive of overall KRAS and KRAS codon 13 mutations were analyzed. RESULTS: KRAS mutations were significantly more common in women than men patients (46.0% vs. 34.4%, P<0.033). However, no sex differences were detected for KRAS mutations by codon subtypes (P=0.592). The Gly13Asp (GGC>GAC) point mutation was identified only within codon 13 in both sexes. For right-sided CRC, KRAS mutations were twice as frequent in men as in women (univariate analysis; P=0.016, multivariate analysis; P=0.019). High-plasma cholesterol level was an independent predictive factor of KRAS codon 13 mutations by univariate (odds ratio, 1.013; 95% confidence interval, 1.003-1.023) and multivariate analysis (odds ratio, 1.011; 95% confidence interval, 1.001-1.021). CONCLUSIONS: Sex differences may affect the presentation of KRAS mutations, as they were more frequently detected in women and in right-sided CRC in men. KRAS codon 13 mutations were significantly associated with high-plasma cholesterol. Further studies are needed on the clinical implications of this finding.
