&NA; Multiple tumor nodules are seen with increasing frequency in clinical practice. On the basis of the 2015 WHO classification of lung tumors, we assessed the reproducibility of the comprehensive histologic assessment to distinguish second primary lung cancers (SPLCs) from intrapulmonary metastases (IPMs), looking for the most distinctive histologic features. An international panel of lung pathologists reviewed a scanned sequential cohort of 126 tumors from 48 patients and recorded an agreed set of histologic features, including tumor typing and predominant pattern of adenocarcinoma, thereby opining whether the case was SPLC, IPM, or a combination thereof. Cohen &kgr; statistics of 0.60 on overall assessment of SPLC or IPM indicated a good agreement. Likewise, there was good agreement (&kgr; score 0.64, p < 0.0001) between WHO histologic pattern in individual cases and SPLC or IPM status, but the proportions diversified for histologic pattern and SPLC or IPM status (McNemar test, p < 0.0001). The strongest associations for distinguishing between SPLC and IPM were observed for nuclear pleomorphism, cell size, acinus formation, nucleolar size, mitotic rate, nuclear inclusions, intraalveolar clusters, and necrosis. Conversely, the associations for lymphocytosis, mucin content, lepidic growth, vascular invasion, macrophage response, clear cell change, acute inflammation keratinization, and emperipolesis did not reach significance with tumor extent. Comprehensive histologic assessment is recommended for distinguishing SPLC from IPM with good reproducibility among lung pathologists. In addition to main histologic type and predominant patterns of histologic subtypes, nuclear pleomorphism, cell size, acinus formation, nucleolar size, and mitotic rate strongly correlate with pathologic staging status.

中文翻译：

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病理学家之间的观察者间差异以及区分肺中单独的原发性肿瘤与肺内转移的标准的细化

&NA; 在临床实践中越来越频繁地看到多个肿瘤结节。在 2015 年 WHO 肺肿瘤分类的基础上，我们评估了综合组织学评估的可重复性，以区分第二原发肺癌 (SPLC) 和肺内转移 (IPM)，寻找最独特的组织学特征。一个国际肺部病理学家小组审查了来自 48 名患者的 126 个肿瘤的连续扫描队列，并记录了一组一致的组织学特征，包括肿瘤分型和腺癌的主要模式，从而判断该病例是 SPLC、IPM 还是它们的组合。科恩 SPLC 或 IPM 总体评估的 0.60 的统计数据表明了良好的一致性。同样，也有很好的一致性（&kgr; 得分 0.64，p < 0。0001）在个别病例的 WHO 组织学模式与 SPLC 或 IPM 状态之间，但组织学模式和 SPLC 或 IPM 状态的比例多样化（McNemar 检验，p < 0.0001）。在核多形性、细胞大小、腺泡形成、核仁大小、有丝分裂率、核内含物、肺泡内簇和坏死方面观察到区分 SPLC 和 IPM 的最强关联。相反，淋巴细胞增多、粘蛋白含量、贴壁生长、血管侵袭、巨噬细胞反应、透明细胞变化、急性炎症角化和周皮的相关性与肿瘤范围无关。推荐全面的组织学评估以区分 SPLC 和 IPM，在肺病理学家中具有良好的可重复性。