The focus on lymph node metastases (LNM) as the most important prognostic marker in colorectal cancer (CRC) has been challenged by the finding that other types of locoregional spread, including tumor deposits (TDs), extramural venous invasion (EMVI), and perineural invasion (PNI), also have significant impact. However, there are concerns about interobserver variation when differentiating between these features. Therefore, this study analyzed interobserver agreement between pathologists when assessing routine tumor nodules based on TNM 8. Electronic slides of 50 tumor nodules that were not treated with neoadjuvant therapy were reviewed by 8 gastrointestinal pathologists. They were asked to classify each nodule as TD, LNM, EMVI, or PNI, and to list which histological discriminatory features were present. There was overall agreement of 73.5% (κ 0.38, 95%-CI 0.33–0.43) if a nodal versus non-nodal classification was used, and 52.2% (κ 0.27, 95%-CI 0.23–0.31) if EMVI and PNI were classified separately. The interobserver agreement varied significantly between discriminatory features from κ 0.64 (95%-CI 0.58–0.70) for roundness to κ 0.26 (95%-CI 0.12–0.41) for a lone arteriole sign, and the presence of discriminatory features did not always correlate with the final classification. Since extranodal pathways of spread are prognostically relevant, classification of tumor nodules is important. There is currently no evidence for the prognostic relevance of the origin of TD, and although some histopathological characteristics showed good interobserver agreement, these are often non-specific. To optimize interobserver agreement, we recommend a binary classification of nodal versus extranodal tumor nodules which is based on prognostic evidence and yields good overall agreement.

淋巴结转移 (LNM) 作为结直肠癌 (CRC) 中最重要的预后标志物的关注受到了其他类型的局部区域扩散的挑战，包括肿瘤沉积 (TDs)、壁外静脉侵犯 (EMVI) 和神经周围入侵（PNI），也有重大影响。然而，在区分这些特征时，人们担心观察者间的差异。因此，本研究分析了病理学家在基于 TNM 8 评估常规肿瘤结节时观察者间的一致性。 8 位胃肠病理学家审查了 50 个未接受新辅助治疗的肿瘤结节的电子幻灯片。他们被要求将每个结节分类为 TD、LNM、EMVI 或 PNI，并列出存在哪些组织学区分特征。总体一致性为 73.5% (κ 0.38, 95%-CI 0.33–0.43)，如果使用节点与非节点分类，52.2% (κ 0.27, 95%-CI 0.23–0.31) 如果 EMVI 和 PNI 分开分类。观察者间的一致性在从圆度的 κ 0.64 (95%-CI 0.58-0.70) 到单独小动脉征的 κ 0.26 (95%-CI 0.12-0.41) 之间存在显着差异，并且区分特征的存在并不总是相关与最终分类。由于结外传播途径与预后相关 并且歧视性特征的存在并不总是与最终分类相关。由于结外传播途径与预后相关 并且歧视性特征的存在并不总是与最终分类相关。由于结外传播途径与预后相关，肿瘤结节的分类很重要。目前没有证据表明 TD 起源的预后相关性，尽管一些组织病理学特征显示出良好的观察者间一致性，但这些通常是非特异性的。为了优化观察者间的一致性，我们建议根据预后证据对结节与结外肿瘤结节进行二元分类，并产生良好的总体一致性。