Colorectal cancer is one of the most common malignant tumors of the digestive system. The incidence of colorectal cancer in China is increasing year by year. Screening for adenomas, precancerous lesions and early cancers can effectively reduce the incidence and mortality of colorectal cancer. Therefore, colorectal cancer screening is particularly important. At present, the colorectal cancer examination is mainly divided into fecal examination and colon structural examination. The fecal examination includes fecal occult blood test, fecal exfoliated cell test and fecal genetic analysis. The colon structural examination includes barium enema, colonoscopy and computed tomography colonography. Colonoscopy is considered as the gold standard for the diagnosis of colorectal cancer. It has the advantage of high accuracy, and can be used to find precancerous lesions and remove them at the same time. However, the screening should be greatly restricted because of its invasive examination, the need for intestinal preparation, obvious discomfort and the high cost of medical treatment. Comparatively, fecal occult blood test is simple, easy, non-invasive, saving manpower and material resources, and is suitable for large population screening. Some scholars in China have begun to pay attention to colorectal cancer screening, and fecal occult blood test is widely used in these screenings.

Objective:To search for valuable laboratory indexes of early diagnosis of anastomotic leakage after anterior resection for rectal carcinoma.Methods:From Sep 2017 to Jan 2019, 128 patients with colorectal cancer underwent anterior rectal resection at the Department of Colorectal & Anal Surgery, the 940 Hospital of the Joint Logistics Support Force.Results:Anastomotic leakage occurred in 16 of 128 patients (12.5%). Definite diagnosis of anastomotic leakage was made on between 2nd and 9th day, postopera tively averagign (6.13±2.00) days. Tumor location was a risk factor for anastomotic leakage with the incidence significantly lower when the distance from the lower edge of the tumor to the anal margin >7 cm than when the distance ≤7 cm ( χ 2=6.022, P=0.014). The percentage of increase in peripheral blood leukocytes, neutrophils, serum interleukin-6, C-reactive protein and procalcitonin in patients 3-5 days after surgery significantly related to the occurrence of anastomotic leakage (all P<0.05). The area under the working characteristic curve of the subjects with the percentage of C-reactive protein, procalcitonin, interleukin-6, leukocytes and neutrophils from the 3rd to the 5th day after operation was greater than 0.5. Conclusion:C-reactive protein, procalcitonin, interleukin-6, leukocyte and neutrophil percentage are risk factors predicting anastomotic leakage after anterior resection of rectal cancer.