Comparative Analysis Of Clinicopathological Features And Prognostic Risk Factors Of Papillary Thyroid Carcinoma In Children And Adults

Background: Thyroid cancer accounts for the majority of all endocrine malignancies in children and adults,but thyroid cancer in children remains rare compared with adults.Pediatric PTC has different characteristics from adult PTC in terms of clinicopathological characteristics and prognosis.This study aims to analyze and compare the prognostic factors of pediatric and adult PTC,establish a specific recurrence risk assessment system for pediatric PTC,and make surgical decisions for different populations.for reference.Methods: This study included 247 children and 1297 adults in a single center for 12 years.After screening,univariate analysis was performed on the recurrence of PTC in children and adults by KM survival curve,fisher’s exact test and univariate COX regression;then Multivariate COX regression was used to explore the independent risk factors affecting the prognosis of PTC in children and adults,and further compared and analyzed;secondly,subgroup analysis of factors affecting prognosis and surgical decision-making was performed to establish a new recurrence risk stratification for children with PTC.Results: The first part: 1.Compared with post-pubertal adolescents,prepubertal children with PTC had larger tumor diameter,higher T stage,and more prone to central lymph node metastasis（p<0.05）.2.Pediatric PTC patients with central cervical lymph node metastasis are younger,have larger tumor diameter,and are more likely to develop lateral cervical lymph node metastasis;children with lateral cervical lymph node metastasis with PTC have larger tumor diameter,bilateral and multifocal tumors,extrathyroidal invasion and central lymph node metastasis were higher.More children with PTC with lateral neck lymph node metastasis chose to undergo total thyroidectomy,and the proportion of patients who underwent RAI treatment after surgery was also more likely,but the prognosis was still relatively poor（p < 0.05）.3.For pediatric PTC,tumor multifocality and tumor diameter >1cm were two independent risk factors for recurrence（HR=4.7,p=0.0266;HR=10.6,p=0.0264）.4.Using the prognostic factors validated in the multivariate COX regression model above—tumor diameter >1 cm and multifocality,a new risk stratification for PTC recurrence in children—Stratification.d was created.Stratification.d can significantly distinguish different degrees of recurrence risk in children with PTC;the higher the stratification of the tumor,the higher the recurrence rate will be（p=0.00027）.The second part: 1.For adult PTC,young（age <35 years）,recurrence of adult PTC patients with larger tumor diameter,multifocal tumor,extraglandular invasion,central and lateral neck lymph node metastasis,and higher pathological stage Higher risk（p < 0.05）.Conclusion: 1.Patients with PTC in the younger age group before puberty have larger tumor diameters,higher T-stage and are more likely to develop central zone lymph node metastases.Pediatric PTC patients with central cervical lymph node metastases were younger,had larger tumor diameters and were more likely to have lateral cervical lymph node metastases.Pediatric PTC patients with lateral cervical lymph node metastases had a higher proportion of larger tumor diameters,multifocal tumours,were located in both lobes,and had extrathyroidal invasion and central cervical lymph node metastases.In pediatric PTC,multifocal tumors and tumor size >1cm in diameter are two independent risk factors for recurrence.A new risk stratification method for recurrence of PTC in children was created----Stratification.d.Stratification.d can significantly differentiate between different levels of risk of recurrence in pediatric PTC patients;the higher the stratification of the tumor,the higher the recurrence rate.3.For adult PTC,the risk of recurrence was higher in young（age <35 years）adult PTC patients with larger tumor diameters,multifocal tumors,extra-glandular invasion,lymph node metastases in the central and lateral cervical regions and higher pathological staging.Of these,the number of lateral cervical lymph node metastases（llnm）is an independent risk factor for PTC in adults.4.Independent risk factors affecting recurrence of PTC in children are mainly tumor diameter and multifocality,the characteristics of the tumor primary within the thyroid gland.The independent risk factor for adult PTC prognosis is lymph node metastasis in the lateral neck region,i.e.,the aggressive nature of the tumor outside the thyroid gland.Nevertheless,total thyroidectomy in all children with PTC is not effective in improving the prognosis,whereas in adults with PTC the focus should be on accurate assessment and complete clearance of the lateral cervical lymph nodes,especially in patients with metastases found in one side of the lateral cervical area,and timely clearance of the contralateral lateral cervical lymph nodes may improve the prognosis.