Papillary Thyroid Microcarcinoma: A Nomogram Based on Clinical and Ultrasound Features to Improve the Prediction of Lymph Node Metastases in the Central Compartment

Abstract

BackgroundAccurate preoperative identification of central lymph node metastasis (CLNM) is essential for surgical protocol establishment for patients with papillary thyroid microcarcinoma (PTMC). We aimed to develop a clinical and ultrasound characteristics-based nomogram for predicting CLNM.MethodsOur study included 399 patients who were pathologically diagnosed with PTMC between January 2011 and June 2018. Clinical and ultrasound features were collected for univariate and multivariate analyses to determine risk factors of CLNM. A nomogram comprising the prognostic model to predict the CLNM was established, and internal validation in the cohort was performed. The Cox regression model was used to determine the risk factors for recurrence-free survival (RFS) and cumulative hazard was calculated to predict prognosis.ResultsThree variables of clinical and US features as potential predictors including sex (odd ratio [OR] = 1.888, 95% confidence interval [CI], 1.160-3.075; P =0.011), tumor size (OR = 1.933, 95% CI, 1.250-2.990; P =0.003) and ETE (OR = 6.829, 95% CI, 3.250-14.350; P <0.001) were taken into account. The predictive nomogram was established by involving all the factors above used for preoperative prediction of CLNM in patients with PTMC. The nomogram showed excellent calibration in predicting CLNM, with area under curves (AUC) of 0.684 (95% CI, 0.635 to 0.774). Furthermore, tumor size, multifocality, presence of ETE, vascular invasion, and CLNM were the significant factors related to the RFS.ConclusionThrough this easy-to-use nomogram by combining clinical and US risk factor, the possibility of CLNM can be objectively quantified preoperatively. This prediction model may serve as a useful clinical tool to help clinicians determine an individual’s risk of CLNM in PTMC, thus make individualized treatment plans accordingly.

A nomogram based on clinicopathological and ultrasound characteristics to predict central neck lymph node metastases in papillary thyroid cancer

“…Nevertheless, men are more likely to develop CNLNM once their immune defenses have been breached. The male sex was believed to be an independent risk factor in the previous research (20)(21)(22)(23). However, the differences in the extent of thyroid cancer in men versus women may not only be related to biological factors.…”

“…Some studies concluded that tumor size ≥1 cm is more likely to develop CNLNM than tumor size <1 cm ( 20 – 22 ), although several studies have not segmented tumors by 1 cm ( 23 – 29 ), and some studies concluded that larger tumor volume is more likely to develop CNLNM ( 30 , 31 ). In sum, CNLNM is generally more likely to occur with larger tumors.…”

“…Therefore, for PTC patients with an ACR score of ≥6, we should increase the emphasis on preoperative screening of cervical lymph nodes and encourage more preoperative examinations to help surgeons more accurately identify metastatic lymph nodes preoperatively for a more scientific surgical protocol, and more active follow-up is also needed. Some studies concluded that tumor size ≥1 cm is more likely to develop CNLNM than tumor size <1 cm (20)(21)(22), although several studies have not segmented tumors by 1 cm (23)(24)(25)(26)(27)(28)(29), and some studies concluded that larger tumor volume is more likely to develop CNLNM (30,31). In sum, CNLNM is generally more likely to occur with larger tumors.…”

Initial ablation ratio predicts the recurrence of low-risk papillary thyroid microcarcinomas treated with microwave ablation: a 5-year, single-institution cohort study

“…Sex, age, and tumor size are considered as risk factors for lymph node metastasis in PTMC patients ( 29 , 30 , 31 ). Our results showed that the RFS was comparable between male and female PTMC patients, although most of the recruited patients were women.…”

Development and validation of a nomogram to predict cancer-specific survival in middle-aged patients with papillary thyroid cancer: A SEER database study

“…Today, many prediction models have been established and applied to TC, but mainly for poor prognostic histological types such as ATC and MTC. The study population is also dominated by middle-aged and children [ [19] , [20] , [21] ]. However, for the middle-aged group with the highest incidence of PTC and long life expectancy, there is still no effective and reliable nomogram to predict prognosis.…”