Objective To analyze the risk factors of central cervical lymph node metastasis (CLNM) and lateral cervical lymph node metastasis (LLNM) in patients with multifocal papillary thyroid cancer (MPTC), and establish prediction models.

Methods A total of 93 MPTC patients were selected as the study objects. They were divided into CLNM group (n=42) and non-CLNM group (n=51) according to the occurrence of CLNM; they were divided into LLNM group (n=31) and non-LLNM group (n=62) according to whether LLNM occurred. Risk factors for CLNM and LLNM in MPTC patients were analyzed, and prediction models were constructed. The predictive efficacy of the model was evaluated by receiver operating characteristic (ROC) curve.

Results The incidence of CLNM and LLNM was 45.16% and 33.33% in 93 MPTC patients. Male, age≤45 years, maximum tumor diameter>10 mm and membrane invasion were the risk factors for CLNM in MPTC patients (P < 0.05); the maximum tumor diameter>10 mm, membrane invasion and CLNM were the risk factors for LLNM in MTPC (P < 0.05). The area under ROC curve (AUC) of CLNM model in MPTC patients was 0.846 (95%CI, 0.749 to 0.947), the sensitivity was 78.21%, and the specificity was 86.07%; the AUC of LLNM model in MPTC patients was 0.848 (95%CI, 0.749 to 0.947), the sensitivity was 76.38%, and the specificity was 82.46%.

Conclusion The male, age≤45 years, maximum tumor diameter>10 mm and capsule invasion are associated with both CLNM and LLNM, and LLNM is associated with the presence of CLNM. The constructed CLNM and LLNM prediction models have good fit and certain prediction value.