Study on Risk Factors of ETE Occurrence and Recurrence in Newly Diagnosed Differentiated Thyroid Carcinoma

Zhengwen Du¹, Xiaowei Yuan^2,*

¹Department of General Surgery, People's Hospital of Dongxihu District, Wuhan, Hubei 430040, China - ²Department of Otorhinolaryngology, People's Hospital of Dongxihu District, Wuhan, Hubei 430040, China

Objective: To explore the risk factors of extrathyroidal extension (ETE) and recurrence in newly diagnosed differentiated thyroid carcinoma patients.

Methods: A total of 296 patients with differentiated thyroid carcinoma who underwent operation in our hospital from January 2015 to September 2018 were retrospectively included, and were divided into ETE group and non-ETE group according to whether ETE occurred, including 50 cases in ETE group and 246 cases in non-ETE group. The clinicopathological data and follow-up survival data were an-alyzed, and the independent risk factors of occurrence and recurrence of ETE were evaluated by uni-variate and multivariate methods.

Results: Univariate analysis showed that tumor length, number of lesions, lymph node metastasis in central or cervical region were all related to the occurrence of ETE in newly diagnosed differentiated thyroid carcinoma patients (P < 0.05). The multivariate analysis of Logistic model showed that the largest diameter of tumor > 2 cm, multiple lesions and cervical lymph node metastasis were independent risk factors for ETE in newly diagnosed differentiated thyroid carcinoma patients (P < 0.05). Univariate analysis showed that the 5-year disease-free survival rate of newly diagnosed differentiated thyroid carcinoma patients was related to the maximum diameter of tumor, the number of lesions, central lymph node metastasis, cervical lymph node metastasis and ETE (P < 0.05). The multivariate analysis of Cox model showed that the maximum diameter of tumor > 2 cm, multiple lesions, cervical lymph node metastasis and ETE were independent risk factors for the 5-year disease-free survival rate of newly diagnosed differentiated thyroid carcinoma patients (P<0.05).

Conclusion: The occurrence of ETE in newly diagnosed differentiated thyroid carcinoma patients is closely related to the maximum diameter of tumor, the number of lesions and lymph node metastasis in cervical region, whereas patients with ETE are more likely to relapse and have poor prognosis.