尽管哨兵淋巴结活检（SLNB）状态是切除性黑素瘤强有力的预测指标，但不必要的SLNB会带来可观的费用和发病负担。本研究旨在利用全国代表性数据开发、验证并呈现个性化、临床决策工具，其中包括临床可操作的概率阈值（预期淋巴转移结果[ELMO]）。利用2000至2017年的监测、流行病学和终末事件登记处（SEER）及2004至2015年的国家癌症数据库（NCDB）开发和内部验证了一种用于SLNB阳性的逻辑岭回归预测模型。外部验证使用了一个大型三级转诊中心的1568名患者。开发队列包括134,809名患者，内部验证队列包括38,518名患者。ELMO（AUC 0.85）的SLNB减少率为29.54%，比先前模型更具有预测T1b、T2a和T2b瘤的SLNB状态的敏感性。外部验证中，ELMO的准确性为0.7586，AUC为0.7218。本研究的局限性是潜在的编码错误、未解释的混淆因素和效应修饰。利用黑色素瘤患者的最大公开数据集开发和验证了ELMO（https://melanoma-sentinel.herokuapp.com/），发现其与其他已发布的模型和基因表达测试相比具有高准确性。针对SLNB阳性的个性化风险评估对于促进医疗保健人员和黑色素瘤患者的全面决策至关重要。©2023年外科肿瘤学会。

Although sentinel lymph node biopsy (SLNB) status is a strong prognostic indicator for cutaneous melanoma, unnecessary SLNBs have substantial cost and morbidity burden.This study was designed to develop, validate, and present a personalized, clinical, decision-making tool using nationally representative data with clinically actionable probability thresholds (Expected Lymphatic Metastasis Outcome [ELMO]).Data from the Surveillance, Epidemiology, and End Results (SEER) Registry from 2000 to 2017 and the National Cancer Database (NCDB) from 2004 to 2015 were used to develop and internally validate a logistic ridge regression predictive model for SLNB positivity. External validation was done with 1568 patients at a large tertiary referral center.The development cohort included 134,809 patients, and the internal validation cohort included 38,518 patients. ELMO (AUC 0.85) resulted in a 29.54% SLNB reduction rate and greater sensitivity in predicting SLNB status for T1b, T2a, and T2b tumors than previous models. In external validation, ELMO had an accuracy of 0.7586 and AUC of 0.7218. Limitations of this study are potential miscoding, unaccounted confounders, and effect modification.ELMO ( https://melanoma-sentinel.herokuapp.com/ ) has been developed and validated (internally and externally) by using the largest publicly available dataset of melanoma patients and was found to have high accuracy compared with other published models and gene expression tests. Individualized risk estimates for SLNB positivity are critical in facilitating thorough decision-making for healthcare providers and patients with melanoma.© 2023. Society of Surgical Oncology.