Value of methylated Septin 9 detection in screening colorectal cancer in elderly people / 中华老年医学杂志

ABSTRACT

Objective To investigate the value of detecting methylated SEPT9 gene (mSEPT9) in serum and stool in screening colorectal cancer in elderly people.Methods Subjects were divided into three groups, the colorectal cancer group (n=82), the colorectal polyps group (n=80) and the healthy control group (n=100).Real-time quantitative polymerase chain reaction (PCR) was used to detect mSEPT9 in peripheral blood and feces.The relationship between mSEPT9 and clinical and pathological characteristics of colorectal cancer was analyzed.The agreement between serum and stool results was analyzed.Results The positive rate of serum mSEPT9 was 73.2％ in the colorectal cancer group, 6.3％ in the colorectal polyps group and 4.0％ in the healthy control group, with statistical significance between the colorectal cancer group and the other two groups (P＜0.01).The sensitivity and specificity for plasma mSEPT9 detection in screening colorectal cancer were 73.2 ％ and 95.6％, respectively.The positive rate was higher in patients with tumor maximum diameter over 3.0 cm, invasion of the entire serosa layer, lower differentiation or advanced clinical staging (P＜0.05).The detection results of plasma mSEPT9 were in complete agreement with those of stool mSEPT9 from the same patients.Conclusions The expression of mSEPT9 is high in elderly patients with colorectal cancer and has a high sensitivity and specificity for PCR detection.Complete agreement can be seen in results from plasma and feces.Detecting mSEPT9 can be a valuable approach to screening colorectal cancer in the elderly.