Clinical Analysis of the Short-Term Outcome of Papillary Thyroid Micro Carcinoma After I Treatment.

Purpose: To explore the factors that influence the short-term clinical outcome after the first I treatment of papillary thyroid micro carcinoma (PTMC).

Patients And Methods: From October 2015 to June 2018, patients who were diagnosed with PTMC with lymph node metastasis were analyzed retrospectively, excluding patients with incomplete clinical data, distant metastasis, positive TGAb, TSH<30 mIU/L. The baseline data of sex, age, time from last surgery to first I treatment, tumor pathology information, and biochemical information were collected before admission. All patients included had radioactive iodine (RAI) with 3.70 GBq. The treatment response of patients was evaluated 6-8 months after discharge. By means of univariate and multivariate analysis, including excellent response (ER) and non-excellent response (NER) groups of clinical data, we assessed the impact of I on patients' outcome. A nomogram model was established based on the above independent risk factors.

Results: A total of 206 patients (59 males and 147 females, mean age 43.4 ± 10.6 years) were included in the study. The median follow-up time was 169.4 ± 10.5 days, including 139 patients in ER group (67.4%) and 67 patients in NER group (32.5%). Four factors including combining Hashimoto's thyroiditis, pre-ablative Tg levels, UIE levels, and lateral lymph node numbers were statistically different between ER group and NER group with significance at < 0.05. Further multivariate analysis showed that Hashimoto's thyroiditis and Ps-Tg levels could be used as independent factors. The model verification showed that the C-index of the modeling set was 0.822, indicating that the nomogram model had a good predicted accuracy.

Conclusion: Our data suggest that coexisting Hashimoto's thyroiditis and elevated Ps-Tg levels are predictive factors for short-term outcome of thyroid micro papillary carcinoma after I treatment. Also, the nomogram model had a good predicted accuracy.