Prognostic Thresholds for Lymph Node Metastasis in Medullary Thyroid Cancer: A Restricted Cubic Splines Analysis

作者：Christina V. Lindsay, Frances Wang, Samantha M. Thomas, Todd W. Frieze, Nicholas A. Frisco, Randall P. Scheri, Hadiza S. Kazaure · 发表于：Thyroid · 年份：2025 · DOI：10.1177/10507256251388406 · 被引用次数：4 · 研究领域：Thyroid Cancer Diagnosis and Treatment、Thyroid and Parathyroid Surgery、Renal cell carcinoma treatment

Objectives: The current American Joint Committee on Cancer medullary thyroid cancer (MTC) staging system qualitatively stratifies lymph node (LN) status based on involved LN compartments; however, American Thyroid Association guidelines note that quantitative assessment of LN metastases “should be incorporated.” Several studies have proposed LN ratio (LNR) and number of positive LNs as prognostic parameters. We (1) assess whether there are prognostically significant LN thresholds, (2) estimate their association with MTC-specific mortality, and (3) appraise the identified thresholds using an institutional database. Methods: In this retrospective cohort analysis, MTC patients were abstracted from the Surveillance, Epidemiology, and End Results database (2004–20). Cox models with restricted cubic splines assessed the functional relationship of LNR and positive LN count with MTC-specific mortality. Thresholds were estimated using Markov Chain Monte Carlo and bootstrapping. Multivariable models estimated the association of the thresholds with mortality. The testing cohort comprised 149 patients with MTC at a single institution (1996–2025). Results: There were 2709 patients in the derivation cohort; 2098 (77.4%) had LNs examined. Mean patient age was 54.1 years, 59.1% were female, and 69.6% were non-Hispanic White. Mean tumor size was 23.5 mm; 52.7% of patients with LNs examined had ≥1 positive LN. The 5-year MTC-specific survival was 93.3%. Threshold values of 7.8 positive LNs and...