RESUMO
Objective:To investigate the value of multi-stage dynamic contrast enhanced MRI (DCE-MRI) histogram in predicting survival of patients undergoing surgical treatment of colorectal cancer (CRC).Methods:The retrospective cohort study was conducted. The clinico-pathological data of 81 patients with CRC who were admitted to the Jiuquan City People′s Hospital from January 2018 to February 2019 were collected. There were 47 males and 34 females, aged (62±6)years. All patients underwent routine MRI and DCE-MRI examination to extract relevant imaging parameters. Observation indicators: (1) treatment, imaging examination and follow-up; (2) imaging factors influencing postoperative disease-free survival of patients with CRC. Measurement data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M(range). Count data were described as absolute numbers. Univariate and multivariate analyses were conducted using the COX proportional risk model. Pearson correlation test was used to analyze and exclude factors with correlation in univariate analysis, and the multi-variate analysis was conducted on the rest of factors. The Kaplan-Meier method was used to calculate survival rates, and Log-Rank test was used for survival analysis. Results:(1) Treatment, imaging examination and follow-up. All 81 patients underwent preoperative MRI plain scan, enhanced imaging, and diffusion weighted imaging. After complete examination, all patients underwent radical resection of CRC and received postoperative chemotherapy using the FOLFOX regimen. All 81 patients were followed up for 42(range, 11-61)months after surgery. The 1-, 3-, 5-year overall survival rate of 81 patients after surgery was 98.8%, 96.3%, 93.8%, respectively. During the follow-up period, 56 of the 81 patients survived from disease-free and 25 patients had disease progressed. (2) Imaging factors influencing postoperative disease-free survival of patients with CRC. Results of multivariate analysis showed that the kurtosis value and skewness value of positive enhancement integral (PEI) were independent imaging factors influencing postoperative disease-free survival of patients of CRC ( odds ratio=1.840, 1.243, 95% confidence interval as 1.403-2.412, 1.020-1.516, P<0.05). Taking the median values of kurtosis value and skewness value of PEI as 4.864 and 5.042 for further analysis. The postoperative 5-year disease-free survival rate of patients with kurtosis value of PEI <4.864 and ≥4.864 was 89.7% and 10.3%, showing a significant difference between them ( χ2=31.265, P<0.05). The postoperative 5-year disease-free survival rate of patients with skewness value of PEI<5.042 and ≥5.042 was 63.4% and 36.6%, showing a significant difference between them ( χ2=8.164, P<0.05). Conclusions:The kurtosis value and skewness value of PEI in DCE-MRI are independent imaging factors influencing postoperative disease-free survival of patients of CRC. The DCE-MRI histogram can effectively evaluate the postoperative prognosis of patients of CRC.