Value of Combining Clinical Factors, Conventional Ultrasound, and Contrast-Enhanced Ultrasound Features in Preoperative Prediction of Central Lymph Node Metastases of Different Sized Papillary Thyroid Carcinomas

Abstract

Purpose Early and accurate preoperative diagnosis of central lymph node metastasis (CLNM) is crucial to improve surgical management of patients with clinical lymph node-negative papillary thyroid carcinoma (PTC). Towards improving diagnosis of CLNM, we assessed the value of combining preoperative clinical characteristics, conventional ultrasound, and contrast-enhanced ultrasound (CEUS) in preoperative prediction of CLNM of different sized PTCs. Patients and Methods Patients were divided according to tumor size: a PTC group (>10 mm) and a papillary thyroid microcarcinoma (PTMC) group (≤10 mm). We retrospectively analyzed the clinical and ultrasonographic features of 120 PTC patients and 165 PTMC patients. Multivariate logistic regression analysis was used to screen independent risk factors and establish prediction models. Receiver operating characteristic curves were used to determine the best cut-off values for continuous variables and assess the performance of prediction models. Results Independent risk predictors of CLNM for the PTC group were extrathyroidal extension in CEUS (OR=7.923), tumor size >14 mm (OR=5.491), and multifocality (OR=3.235). For the PTMC group, the independent risk factors were the distance from the thyroid capsule =0 mm (OR=4.629), male (OR=3.315), tumor size >5 mm (OR=3.304), and microcalcification (OR=2.560). The predictive model of combined method had better performance in predicting CLNM of PTC compared with models based on CEUS and conventional ultrasound alone (area under the curve: 0.832 vs 0.739, P =0.0011; 0.832 vs 0.678, P =0.0012). For PTMC, comparing with CEUS, the combined method and conventional ultrasound performed better than CEUS alone in predicting CLNM (area under the curve: 0.783 vs 0.636, P =0.0016; 0.738 vs 0.636, P =0.0196). Conclusion The predictive models of combined method obtained from significant preoperative clinical and ultrasonographic features can potentially improve the preoperative diagnosis and individual treatment of CLNM in patients with PTC and PTMC. CEUS may be helpful in predicting CLNM of PTC, but CEUS would be ineffective in predicting CLNM of PTMC.

Ultrasound and Contrast-Enhanced Ultrasound Characteristics Associated With cN1 and Microscopic pN1 in Papillary Thyroid Carcinoma

“…( 36 ) reported that old age was a risk factor of LNMs. Multifocality has been reported to be associated with an increased risk of LNMs ( 8 , 32 , 37 , 38 ) and it was identified to be an independent risk factor of microscopic pN1 in our study.…”

Establishing a Predictive Nomogram for Cervical Lymph Node Metastasis in Patients With Papillary Thyroid Carcinoma

“…The nomogram model was established using the seven independent risk predictors: gender, age, multifocality, tumor size, extracapsular invasion, boundary, and US suggested CLNM (Figure 3). The model score axis (2)(3)(4)(5)(6)(7)(8)(9) corresponded to the score of each predictor from bottom to top, and then the total score was calculated to find the risk of CLNM corresponding to the last risk axis. The C-index of the nomogram was 0.940 (95% CI, 0.888-0.991), suggesting that the nomogram model has a favorable prediction performance of CLNM.…”

“…PTC is more common in female patients, and the incidence rate in women is three times that in men. Although PTC is considered to be an indolent tumor with low malignancy, slow disease progression, and good prognosis ( 2 ), 20–50% of patients still have early cervical lymph node metastasis (CLNM), leading to a high risk of local recurrence ( 3 ).…”

The Role of CEUS in the Evaluation of Thyroid Cancer: From Diagnosis to Local Staging

“…The six largest studies regarding differentiation between benign and metastatic cervical lymp nodes, conducted between 2014 and 2019, show that CEUS has a good diagnostic accuracy superior to standard US and Color-Doppler grayscale alone [ 59 , 74 , 77 , 78 , 79 ] ( Table 1 ).…”

“…In particular: L/S ratio < 2, ill-defined margins, hyper-echogenicity, cystic necrosis, calcification and peripheral vascularity are found at baseline US; meanwhile, centripetal or asynchronous perfusion (Figure 2a,b), non-or hyper-enhancement, perfusion defects and ring enhancing margins are found using CEUS; lymph nodes with one or more of the previous features are considered metastatic [77]. The six largest studies regarding differentiation between benign and metastatic cervical lymp nodes, conducted between 2014 and 2019, show that CEUS has a good diagnostic accuracy superior to standard US and Color-Doppler grayscale alone [59,74,[77][78][79] (Table 1). 3 The study divides patients into two groups, PTC (>10mm), PTMC (<10mm); 4 The evaluation is based on a prediction model combining both the parameters obtained from the CEUS and clinical parameters.…”