Abstract:

Objective To explore the diagnostic value of CT ⁃ based radiomics nomogram in predicting lymph node metastasis of head and neck cancer. Methods A retrospective analysis was performed on the patients who visited the first people′s Hospital of Hefei from January 2017 to October 2020. They had clear lymph node pathology and had good quality CT scan before treatment. A total of 201 lymph nodes were collected from 75 patients with head and neck malignant tumors. One hundred and thirteen lymph nodes from January 2017 to November 2019 were enrolled into the training group，and 88 lymph nodes from December 2019 to October 2020 were enrolled into the test group. Mazda software was used to extract the radiomics features，and lasso method was used to reduce the dimension and establish the radiomics tags. After the multivariate logistic regression screening，the plain scan CT value，enhanced arterial phase CT value and radiomics tags were seperately used to establish radiomics nomogram diagnostic models. Receiver operator characteristic（ROC）curve，area under curve（AUC）and calibration curves were used to evaluate the diagnostic efficacy. Results In each CT scan，298 3D features were extracted from the cervical lymph node region. Through dimensionality reduction，6 ~ 7 most relevant radiomics features were selected to establish the radiomics tags. The AUC of nomograph prediction model of radiomics tags plus plain CT value in training set and test set was（0.955，0.885），and that of radiomics tags plus enhanced CT value in training set and test set was（0.982，0.920），which were higher than that in the only radiomics tags model（0.940，0.905）（P < 0.05）. The accuracy of plain CT value plus plain radiomics tags，enhanced CT value plus radiomics tags，radiomics tags and CT sign diagnosis model were 0.920，0.930，0.801 and 0.716，respectively，and the sensitivity was 0.925，0.925，0.877 and 0.792，respectively，and the specificity was 0.916，0.926，0.716 and 0.632，respectively. At the same time，it had satisfactory calibration. Conclusion CT⁃based radiomics nomogram has a good diagnostic effect on lymph node metastasis of head and neck cancer，which is simple，safe and reliable.

Key words:

head and neck lymph nodes, computed tomography, radiomics, nomogram