Purpose: Papillary thyroid carcinomas (PTCs) frequently metastasize to the central neck compartment. Therapeutic central compartment neck dissection (CCND) is a well-established treatment for PTC nodal metastases; however, the extent to which therapeutic CCND should be performed remains controversial. In this study, we investigated the predictive risk factors for contralateral paratracheal lymph node metastasis (LNM) in unilateral cT1N1a or cT2N1a PTC.
Patients and Methods: In this case–control study, which was conducted at a single center, demographic and pathological data from unilateral cT1N1a or cT2N1a PTC patients were collected from January 2017 to March 2019. All patients were treated with total thyroidectomy and bilateral CCND.
Results: Two hundred thirty-seven patients met the inclusion criteria. Forty-nine patients (20.7%) were diagnosed with positive lymph nodes in the contralateral paratracheal region. Male sex (p=0.003), T2 disease (21– 40 mm) (p< 0.001), inferior pole tumor (p=0.011), near isthmus tumor (p< 0.001), aggressive pathology (p< 0.001), intraglandular dissemination (p=0.009), pretracheal LNM (p< 0.001), > 5 metastatic lymph nodes (p< 0.001) and extranodal invasion (p=0.003) were significantly associated with contralateral paratracheal LNM in univariate analysis. Multivariate analysis showed that male sex (p=0.005, OR=17.545), T2 disease (p=0.003, OR=34.317), inferior pole tumor (p=0.022, OR=8.289), near isthmus tumor (p=0.001, OR=40.229), aggressive pathology (p=0.027, OR=48.063), pretracheal LNM (p=0.002, OR=14.235) and > 5 metastatic lymph nodes (p=0.025, OR=23.426) were independent risk factors for contralateral paratracheal LNM.
Conclusion: Male sex, T2 disease, a tumor located near the isthmus or inferior pole, aggressive pathology, pretracheal LNM and > 5 metastatic lymph nodes were predictive factors for contralateral paratracheal LNM in unilateral cT1N1a or cT2N1a PTC. These data may be useful to identify targets for surveillance or develop therapeutic interventions for patients with CCND.
Keywords: papillary thyroid carcinoma, central compartment neck dissection, predictive factor, lymph node metastasis