Diffusion kurtosis imaging in identifying the malignancy of lymph nodes during the primary staging of rectal cancer.

Abstract

The aim was to assess the diagnostic value of diffusion kurtosis imaging (DKI) for discriminating between benign and malignant lymph nodes in patients with rectal carcinoma. ighty-five patients with rectal adenocarcinoma who underwent total mesorectal excision of the rectum were studied. A total of 273 lymph nodes were harvested and subjected to histological analysis. Quantitative parameters [apparent diffusion parameter Dapp of the Gaussian distribution, apparent kurtosis coefficient Kapp and apparent diffusion coefficient (ADC)] of lymph nodes were derived from DKI. Differences and the diagnostic performance of these parameters were calculated by using the independent-samples t test and receiver operating characteristic curve analyses. The median Dapp and ADC values of metastatic lymph nodes were significantly greater than those of benign lymph nodes, whereas the median Kapp of metastatic lymph nodes was statistically less than that of normal lymph nodes. Dapp had the relatively highest area under the curve of 0.774. When 1126.15×10-6 mm2 /s was used as a Dapp threshold value, the sensitivity and specificity were 96.97% and 41.82%, respectively. DKI can help differentiate metastatic vs benign lymph nodes during the primary staging of rectal cancer.