Department of Pathology, University of Western Ontario, London, ON, Canada.
Am J Surg Pathol. 2012 Apr;36(4):570-6. doi: 10.1097/PAS.0b013e31824057e7.
The response of colorectal adenocarcinoma liver metastases to perioperative chemotherapy can be assessed histologically in partial hepatectomy specimens. Necrosis in this scenario may represent a lack of treatment effect or a therapeutic response to chemotherapy. This study sought to validate the histologic classification of necrosis into 2 types: usual necrosis (UN) representing an absence of treatment effect, and infarct-like necrosis (ILN) representing a therapeutic response to chemotherapy. Tumor regression grade (TRG) is a previously described prognosticating method that estimates tumor replacement by fibrosis. We incorporated ILN into a modified TRG (mTRG) and compared its performance as a prognostic factor against TRG. A retrospective clinical and histologic review was undertaken of all partial hepatectomies performed for colorectal liver metastases at our center between 2004 and 2010. Clinicopathologic features were compared between the 2 types of necrosis, including survival stratified by TRG and mTRG. A total of 109 cases were reviewed, with 46 patients receiving perioperative chemotherapy. ILN was identified in 12 cases, and all of these cases were associated with perioperative chemotherapy. ILN was significantly associated with perioperative treatment with bevacizumab. In patients receiving perioperative chemotherapy, those with ILN had superior disease-free survival compared with those with UN (P=0.047). mTRG1 to 2 scores were associated with significantly better survival compared with mTRG3 to 5 scores. In contrast, use of TRG did not demonstrate a significant difference in disease-free and overall survival. ILN represents a form of treatment effect and should be distinguished from UN. A modified grading system that incorporates ILN may enhance the prognostic utility of TRG.
结直肠癌肝转移患者的围手术期化疗疗效可通过部分肝切除标本的组织学评估。在这种情况下，坏死可能代表缺乏治疗效果或对化疗的治疗反应。本研究旨在验证将坏死分为两种类型的组织学分类：通常的坏死（UN）代表缺乏治疗效果，而类似梗塞的坏死（ILN）代表对化疗的治疗反应。肿瘤退缩分级（TRG）是一种先前描述的预后方法，用于估计纤维化对肿瘤的替代程度。我们将 ILN 纳入改良的 TRG（mTRG）中，并比较其作为预后因素的表现与 TRG。对 2004 年至 2010 年期间在我们中心进行的所有结直肠癌肝转移部分肝切除术的临床和组织学回顾进行了回顾性分析。比较了两种类型的坏死的临床病理特征，包括按 TRG 和 mTRG 分层的生存情况。共回顾了 109 例病例，其中 46 例接受了围手术期化疗。在 12 例中发现了 ILN，所有这些病例均与围手术期化疗相关。ILN 与围手术期贝伐单抗治疗显著相关。在接受围手术期化疗的患者中，ILN 患者的无病生存率明显优于 UN 患者（P=0.047）。mTRG1 至 2 评分与显著更好的生存相关，而 mTRG3 至 5 评分则相反。相比之下，TRG 的使用并未在无病生存和总生存方面显示出显著差异。ILN 代表一种治疗效果，应与 UN 区分开来。一种纳入 ILN 的改良分级系统可能会提高 TRG 的预后实用性。
