To explore the feasibility of grey histogram texture analysis based on CT contrast enhancement in preoperative evaluation of the degree of malignancy of pancreatic cancer, and to evaluate the relationship between grey histogram parameters and pathological grade and differentiated degree of pancreatic cancer.

A total of 49 patients with postoperative pathology proven pancreatic cancer including high differentiation(27 cases)and low-moderate differentiation(22 cases)were analyzed retrospectively.Region of interest(ROI)was chosen at axial CT images with maximum enhancement of lesion and grey histogram analysis was performed using Mazda software.The histogram parameters were analyzed statistically in these two groups.Receiver operating characteristic(ROC)curve was established for parameters to compare diagnostic performance.In addition, the correlation was tested between parameters and groups.

In the 9 parameters extracted from grey histogram analysis among the two groups, the mean value, Perc.01%, Perc.10%, Perc.50% had statistical differences(P<0.05), but variance, skewness, kurtosis, Perc.90%, Perc.99% had not statistical differences(P>0.05). Spearman correlation analysis showed that the mean value, Perc.01%, Perc.10%, Perc.50% were positively correlated with the differentiated degree(r values were 0.04, 0.29, 0.32 and 0.33 respectively, P<0.05). When evaluating malignant grade of pancreatic cancer, the diagnostic efficiency of the mean value was the highest(AUC=0.695). When the cutoff value was 147.27 for mean value, the sensitivity and specificity were 86.4% and 44.4%.When the cutoff value was 117 for Perc.01%, the sensitivity and specificity were 95.5% and 40.7%.When the cutoff value was 120 for Perc.10%, the sensitivity and specificity were 72.7% and 63%.When the cutoff value was 146 for Perc.50%, the sensitivity and specificity were 86.4% and 44.4%.

The characteristic parameters of gray histogram texture analysis based on CT enhanced images are different between high and low-moderate grade pancreatic cancer, providing a new method for preoperative evaluation of the degree of malignancy of pancreatic cancer.