Metastases to lymph nodes from monofocal and multifocal papillary thyroid malignant tumors in patients with autoimmune thyroiditis

The aim of this work was to study the risk factors for metastasis to the central and lateral neck lymph nodes in papillary thyroid carcinoma (PTC) and multifocal papillary thyroid carcinoma (MPTC), especially in patients with Hashimoto’s thyroiditis (TH). Methods: A retrospective analysis of 763 patients after thyroidectomy with bilateral central lymphadenectomy (CLE) was performed at the interterritorial Center for Endocrine Surgery in Krasnodar during the period from October 2011 to October 2021. All patients had official histological diagnoses of TH. To identify risk factors for metastasis (Mts) to the lymph nodes of the neck, a multifactorial logistic regression analysis was performed. Results: In our study, 277 patients with SCLC and TC showed relatively low rates of Mts to the central lymph nodes (CLU) compared with patients with SCLC without TC (37.2 % vs. 54.7 %, P  140 IU / ml was established as the most sensitive and specific level for predicting MPCT based on the study. Antibodies to AT-TPO, age, tumor size, and multifocal tumor shape demonstrated the ability to predict Mts in the central nervous system in patients with PCT on the background of TC with a probability of 81.1 % based on a multidimensional model. TH was associated with an increased prevalence of multifocal tumor with invasion of the gland capsule. Conclusions: TH detection demonstrated the reduced risk of metastases to the CLN in patients with PCT and MPCT and indicated a potential protective effect. We found that the prognostic model is applicable for predicting a multifocal tumor and metastasis to the central nervous system in patients with PCT and TH.