Abstract:Background and Aims Although the incidence rate of thyroid cancer among children and adolescents is considerably lower than that among adults, it is still increasing over time, and thyroid cancer has become one of the relatively common malignant tumors in children and adolescents. Compared with adults, thyroid cancer in children and adolescents have some different clinical characteristics, and further investigating these characteristics may facilitate more precise diagnosis and treatment planning. Therefore, this study was performed to investigate the clinicopathologic features and prognosis of thyroid cancer in children and adolescents through a retrospective analysis, so as to provide a reference for treatment decisions in clinical practice.Methods The data of 68 pediatric and adolescent patients (≤20 years old) undergoing surgery for thyroid diseases in the First Affiliated Hospital of Hunan Normal University (Hunan Provincial People's Hospital) from September 2014 to June 2021 were collected. The patients with thyroid cancer receiving follow-up were included for study. In addition, 22 adult patients with thyroid cancer were randomly selected as control. The differences in clinical characteristics and prognosis between the two groups of thyroid cancer patients were compared.Results Among the 68 pediatric and adolescent patients, 24 cases (35.29%) were pathologically diagnosed as thyroid cancer, of whom, 22 cases receiving a follow-up for 3 to 27 months. Of the 22 patients, 19 were females and 3 were males (6.33∶1); age ranged from 3 to 20 years with an average age of (16.73±4.52) years; the course of the disease ranged from 10 d to 5 years with an average of 9.5 months; hospital admission was mainly due to palpation of a painless mass in the neck; TI-RADS 4 and 5 nodules accounted for a high proportion (19/22, 86.36%) in preoperative thyroid ultrasound; 3 cases underwent thyroid lobectomy of the affected side, one case underwent thyroid lobectomy of the affected side plus contralateral subtotal thyroidectomy, 2 cases underwent thyroid lobectomy of the affected side plus contralateral proximal total thyroidectomy, and the remaining cases all underwent total thyroidectomy; 21 cases received central compartment lymph node dissection, 13 cases received lateral lymph node dissection, and one case did not undergo lymph node dissection. The postoperative pathology showed that 18 cases (81.82%) were papillary thyroid carcinoma (PTC), 3 cases (13.64%) were papillary thyroid microcarcinoma (PTMC), and one case (4.54%) was medullary thyroid carcinoma (MTC). After operation, unilateral recurrent laryngeal nerve injury occurred in 3 cases, laryngeal edema occurred in one case, hypoparathyroidism occurred in 2 cases, and chylous leakage occurred in one case after lymph node dissection in the left lateral cervical region. Recurrence occurred in one patient with MTC about 3 years later, and then the patient underwent extended bilateral lymph node dissection and targeted drug therapy. The gender distribution of thyroid cancer in children and adolescents was basically the same as that in adults; PTC was the most common pathological type of thyroid cancer for pediatric and adolescent thyroid cancer patients and adult thyroid cancer patients (95.45% vs. 100.00%), but the proportion of PTMC in the former was significantly lower than that in the latter (13.36% vs. 50.00%, P<0.05); in addition, the cervical lymph node metastasis accounted for 77.27% (17/22) in pediatric and adolescent patients, in which the proportion of bilateral cervical lymph node metastasis was significantly higher than that in adult patients (50.00% vs. 9.09%, P<0.05).Conclusion Thyroid cancer accounts for a relatively high proportion of thyroid diseases in children and adolescents. The patients' sex and pathological type of thyroid cancer in children and adolescents are similar to those in adults, but the tumor size at diagnosis is often larger than that of adults, and bilateral cervical lymph node metastasis is more likely to occur. However, after standardized treatment such as surgery, the overall prognosis is better.