Features of regional relapses in the central zone after surgical treatment of highly differentiated thyroid cancer

Introduction. Thyroid cancer is the most common malignant tumor of the endocrine system and comprises 33 % of malignant neoplasms of the head and neck. first echelon lymph nodes affected by this pathology are located in the central area of the neck. The metastatic process further advances into the lymph nodes in the lateral tissues of the neck. Currently, there is no consensus on the effectiveness of prophylactic central lymph node dissection and no conclusive criteria determining the risk of recurrence in the central zone.

Aim. The assessment of factors influencing the risk of regional recurrence in the central zone.

Materials and methods. The study included 30 patients with highly differentiated thyroid cancer, in whom metastatic nodes in the central zone were identified and verified during primary treatment. All patients previously underwent unilateral or 2-sided central lymph node dissection in various institutions. During the period of dynamic observation, these patients revealed regional recurrence in the central zone. patients were observed and treated for recurrence at the National medical Research Center of Oncology named after N.N. Blokhin of the ministry of Health of Russia.

Results. primary surgical treatment in a specialized oncological institution was performed in 21 (70 %) patients, in a general surgical medical institution – in 7 (23.3 %), in an endocrinological institution – in 2 (6.7 %) patients. when assessing the influence of the morphological type and variant of thyroid cancer on the risk of developing regional recurrence,  no  statistical  significance  was  found.  No  statistically  significant  factors  were  found  in  the  analysis  of  the influence of characteristics of the primary tumor, such as tumor size, multifocal lesion, vascular invasion, extrathyroidal spread, on the risk of regional recurrence. In 16 (53.3 %) patients, recurrence occurred in the paratracheal zone of the ipsilateral side, in 7 (23.3 %) patients in the paratracheal zone of the contralateral side, bilateral lesions were observed in 2 (6.67 %) cases. 3 (10 %) patients were diagnosed with transient parathyroid insufficiency, 1 (3.3 %) – permanent parathyroid insufficiency, 1 (3.3 %) – hematoma in the area of the postoperative wound, patient, 2 (6.6 %) – injury to the recurrent laryngeal nerve.

Conclusion. Residual metastatic lymph nodes after previous surgical treatment are the reason for performing a second operation, which carries both the risks of postoperative complications and the psychological burden on the patient. Thus, an adequate and radically performed primary surgical intervention is the key to reducing regional recurrences.