Study on the correlation between inteavoxel incoherent motion parameters and histologic type and pathological grade of rectal cancer

ObjectiveTo explore the correlation between inteavoxel incoherent motion(IVIM) parameters and histologic type and pathological grade of rectal cancer.

MethodsTwenty-nine patients with common adenocarcinoma of rectum and 12 patients with mucinous adenocarcinoma diagnosed by pathology were divided into the common group and mucinous group, respectively.Two groups were detected using routine MR and IVIM scan(b=0, 10, 20, 50, 100, 200, 400, 800, 1 200, 2 000 s/mm²) before operation.The apparent diffusion coefficient(ADC), true diffusion coefficient(D), pseudo-diffusion coefficient(D*) and perfusion score(f value) were compared between two groups.The diagnostic efficiency of parameters were evaluated using receiver operating characteristic curve(ROC).

ResultsThe ADC, D and f value in common group were significantly lower than that in mucinous group(P < 0.01).The differences of the ADC, D and f value in different pathology grades patients in common group were not statistically significant(P>0.05).The results of ROC analysis showed that the optimal threshold value, sensitivity, specificity and area under the curve ROL in common adenocarcinoma of rectum patients and mucinous adenocarcinoma diagnosed by the ADC, D and f value were 0.998×10³ mm²/s, 88.3%, 55.7%, 0.748, 0.81×10^-3 mm²/s, 91.7%, 72.9%, 0.814, 43.0%, 75.0%, 72.9% and 0.758, respectively.

ConclusionsIVIM parameter can quantitatively reflect the characteristics of cell density and perfusion of different histological types of rectal cancer.The D value has the highest diagnostic efficiency, which is helpful for preoperative prediction and making of clinical treatment plans.