大约5%的转移性癌症存在来源不明的情况，分子分类可以影响后续管理，然而，关于临床影响方面，分子诊断分类器的先前研究结果不一致。本回顾性研究评估了一种新型分子诊断分类器的实用性，通过评估癌症诊断师在审查分类器预测结果之前与之后在治疗和额外检测建议方面的理论改变。 我们回顾性分析了289名无法确定/未知原发部位（CUP）癌症共识诊断的患者的匿名记录。两名（或三名，如果需要仲裁）独立的肿瘤科医生分别审查患者的临床信息，以确定治疗方案，然后评估预测诊断是否会改变他们的治疗计划。 分子诊断分类器的结果改变了289名患者中的235名（81.3%）的共识肿瘤科医生报告的治疗建议。在个别肿瘤科医生的审查中（n=414），64.7%（n=268）的治疗建议在审查分子诊断分类器结果之前基于CUP指南。在看到分类器结果后，98.1%（n=207）的具体治疗建议评审（n=211）参照了原发组织特异性指南。总体上，414个评审中的89.9%表示强烈一致（n=242）或一致（n=130），即分子诊断分类器结果增加了选择最合适治疗方案的信心。 CUP病例的回顾性审查表明，一种新型分子诊断分类器可以影响大多数患者的治疗，支持其临床实用性。进一步研究需要前瞻性评估分子诊断分类器是否改善CUP患者的临床结局。 版权所有© 2023作者。由John Wiley & Sons Ltd出版的《癌症医学》发布。

Roughly 5% of metastatic cancers present with uncertain origin, for which molecular classification could influence subsequent management; however, prior studies of molecular diagnostic classifiers have reported mixed results with regard to clinical impact. In this retrospective study, we evaluated the utility of a novel molecular diagnostic classifier by assessing theoretical changes in treatment and additional testing recommendations from oncologists before and after the review of classifier predictions.We retrospectively analyzed de-identified records from 289 patients with a consensus diagnosis of cancer of uncertain/unknown primary (CUP). Two (or three, if adjudication was required) independent oncologists separately reviewed patient clinical information to determine the course of treatment before they reviewed results from the molecular diagnostic classifier and subsequently evaluated whether the predicted diagnosis would alter their treatment plan.Results from the molecular diagnostic classifier changed the consensus oncologist-reported treatment recommendations for 235 out of 289 patients (81.3%). At the level of individual oncologist reviews (n = 414), 64.7% (n = 268) of treatment recommendations were based on CUP guidelines prior to review of results from the molecular diagnostic classifier. After seeing classifier results, 98.1% (n = 207) of the reviews, where treatment was specified (n = 211), were guided by the tissue of origin-specific guidelines. Overall, 89.9% of the 414 total reviews either expressed strong agreement (n = 242) or agreement (n = 130) that the molecular diagnostic classifier result increased confidence in selecting the most appropriate treatment regimen.A retrospective review of CUP cases demonstrates that a novel molecular diagnostic classifier could affect treatment in the majority of patients, supporting its clinical utility. Further studies are needed to prospectively evaluate whether the use of molecular diagnostic classifiers improves clinical outcomes in CUP patients.© 2023 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.