Utility and significance of clinical risk factor scoring model in predicting central compartment lymph node metastasis (CLNM) in patients with papillary thyroid cancer (PTC)

OBJECTIVES: To establish and discuss the significance of a clinical risk factor scoring model in predicting central compartment lymph node metastasis (CLNM) (level VI) in patients with papillary thyroid cancer (PTC). METHODS: A retrospective analysis was performed on 412 patients who underwent surgical treatment for PTC who were admitted to the Second Hospital of Hebei Medical University between July 2016 and May 2017, with the patients being divided into a CLNM group and a non-metastasis (NM) group. Risk factors such as sex, age, tumor diameter, capsular invasion, multifocality, and tumor location were recorded for scoring via maximum likelihood estimation (MLE)-based discriminant analysis. The scoring model was used for prospective analysis of CLNM in another 104 patients. Besides, the discriminant function that was developed using the risk factors based on the retrospective data derived from the 412 patients was evaluated by plugging the retrospective data in for specified variables, with a higher score indicating a greater risk of developing CLNM. Clinical diagnosis of CLNM was based on postoperative paraffin section pathology, which was adopted as the criterion to assess discriminative accuracy in the prospective and retrospective groups. RESULTS: The discriminative accuracy of the scoring model was 71.8% in the retrospective group and 72.2% in the prospective group. CONCLUSIONS: The scoring model enables simplified, quantitative analysis of CLNM in PTC patients. The scoring model has clinical significance in that it provides a basis for the choice of operation, personalized postoperative treatment, and prognosis of PTC.