Evaluation of Septin9, SDC2, TFPI2 methylation and fecal occult blood in the screening of large intestine lesions / 中华检验医学杂志

ABSTRACT

Objective:To investigate the clinical application value of peripheral blood methylation Septin9 gene in peripheral blood combined with SDC2 gene methylation and TFPI2 gene methylation and fecal occult blood test in colorectal lesion screening.Methods:Through random-selection method. Seventy-five patients with colorectal cancer and 50 patients with advanced adenoma who were treated in our hospital from January 2017 to June 2019 were enrolled as the colorectal cancer group and the advanced adenocarcinoma group, respectively, and the results of the negative test were used as controls Methylation-specific PCR (MSP) was used to detect the methylation status of the Septin9, SDC2 and TFPI2 genes in all patients and the fecal occult blood test for colorectal cancer and advanced adenocarcinoma. In addition, the receiver operating characteristic curve (ROC curve) was drawn to compare the diagnostic value of combined detection and individual detection.Results:The positive rate of Septin9, SDC2, TFPI2 methylation and FOBT in colorectal cancer group was 53.04% (61/115 cases), 55.65% (64/115 cases), 59.13% (68/115 cases) and 26.09% (30/115 cases), respectively. The positive detection rates of Septin9, SDC2, TFPI2 methylation and FOBT in the advanced adenoma group were 33.33% (30/90 cases), 50% (45/90 cases), 40.00% (36/90 cases) and 17.78% (16/90 cases), respectively. The detection sensitivity (82.7%) was higher than the sensitivity of each single test and combined detection of SDC2 and TFPI2 gene methylation Septin9 methylation (66.7%), SDC2 methylation (69.3%), TFPI2 methylation (73.3%), FOBT (26.7%), SDC2 and TFPI2 methylation combined detection (77.3%), while maintaining a high specificity (80.0%). Septin9, SDC2, TFPI2 gene methylation joint inspection screening advanced adenomas detection sensitivity (70.0%) was higher than the sensitivity of each single test and combined detection of SDC2 and TFPI2 gene methylation (40.0%), SDC2 Septin9 gene methylation gene methylation (64.0%), TFPI2 methylation (50.0%), FOBT (18.0%), SDC2 and TFPI2 gene methylation detection (64.0%), and also maintained a high specificity (82.5%). ROC curve analysis showed that the area under the ROC curve of the three gene methylation combined screening for colorectal cancer was significantly higher than that of Septin9, SDC2, TFPI2 gene methylation, FOBT alone, and SDC2 combined with TFPI2 gene methylation detection (0.684, 0.765, 0.623, 0.796 and 0.566), and the difference was statistically significant ( P<0.05); and the area under the ROC curve of three gene methylation combined screening screening for advanced adenomas was significantly higher than the area under the ROC curve of Septin9, SDC2, TFPI2 gene methylation, FOBT alone, and SDC2 combined with TFPI2 gene methylation (0.568, 0.685, 0.535, 0.723 and 0.489), and the difference was statistically significant ( P<0.05). Conclusions:Combined detection of Septin9, SDC2 and TFPI2 gene methylation can improve the sensitivity of colorectal lesion diagnosis and maintain high specificity. It has the clinical application value for early screening and diagnosis and treatment of colorectal cancer.