Analysis of association of MLH1 and PMS2 gene expression with clinicopathological features in elderly patients with colorectal cancer / 中华老年医学杂志

ABSTRACT

Objective:To analyze the expression of mismatch repair genes MLH1 and PMS2 in elderly colorectal cancer patients and its association with the clinicopathological features.Methods:This study was a single-center retrospective cohort study.According to the loss of MLH1 and PMS2 gene expression, elderly patients with colorectal cancer admitted to Beijing Hospital from January 2014 to December 2018 were consecutively enrolled and divided into the MLH1 group(n=65)and the PMS2 group(n=80). Pathological features were compared between the MLH1 group, the PMS2 group and patients with normal MLH1 and PMS2 gene expression.Results:Among patients with the loss of MHL1 protein expression, pathological features were similar in males and females.A minority of patients(16.9%)had a family history of tumors.Most lesions were either moderately differentiated(63.1%)or poorly differentiated(24.6%). Regarding staging, 44.6% were in stage T4, 27.7% were in stage T3, 61.5% were in N0, 89.2% were in M0, and most patients were in TNM stage Ⅲ.Lesions were mostly located in the ascending colon(61.5%). Compared with patients with normal expression of MHL1, patients with the loss of MHL1 protein expression were younger[(74.6±8.8) years old vs.(77.3±6.2) years old, t=-2.072, P=0.040]and had greater maximal tumor length[(5.7±2.3) cm vs.(4.4±1.3) cm, t=3.753, P<0.001], and there were significant differences in lesion differentiation, T staging and tumor location between the two groups( P<0.05). Conclusions:Loss of MLH1 or PMS2 gene expression in elderly colorectal cancer patients is associated with an early age of onset, rapid tumor progression, poor differentiation, and pathological staging.