Faria P, Beckwith J B, Mishra K, Zuppan C, Weeks D A, Breslow N, Green D M
Department of Pathology and Human Anatomy, Loma Linda University, CA 92350, USA.
Am J Surg Pathol. 1996 Aug;20(8):909-20. doi: 10.1097/00000478-199608000-00001.
Anaplasia, defined by the presence of extreme nuclear and mitotic atypia, is a potent marker of adverse prognosis in Wilms tumor (WT). Anaplastic WT cells apparently have increased resistance to therapy rather than increased aggressiveness. The distribution of anaplasia should therefore have critical prognostic relevance. The original definitions for focal anaplasia (FA) and diffuse anaplasia (DA) were based on quantitative rather than topographical criteria and lacked prognostic significance. A new definition was developed based on the distribution of anaplastic changes within the tumor: FA applies only to tumors with anaplasia confined to one or a few discrete loci within the primary tumor, with no anaplasia or marked nuclear atypia elsewhere. This revised definition was evaluated in 165 cases with anaplastic WT entered on the third and fourth National Wilms Tumor Study. Only three relapses and one death occurred among 39 cases with FA, regardless of tumor stage, a result comparable to that for nonanaplastic WT. Eight children with metastases at diagnosis and FA in the primary tumor were alive and free of relapse; 22 of 23 children with stage IV DA WT died of tumor. This new definition reinforces the importance of carefully documenting the exact site from which each tumor section is obtained.
间变是指存在极端的核异型性和有丝分裂异型性，是肾母细胞瘤（WT）不良预后的有力标志物。间变性WT细胞显然对治疗的抗性增加，而非侵袭性增强。因此，间变的分布应具有关键的预后相关性。局灶性间变（FA）和弥漫性间变（DA）的原始定义基于定量而非地形学标准，且缺乏预后意义。基于肿瘤内间变改变的分布制定了一个新定义：FA仅适用于间变局限于原发肿瘤内一个或几个离散部位，其他部位无间变或明显核异型性的肿瘤。在第三和第四次全国肾母细胞瘤研究中登记的165例间变性WT病例中对这一修订定义进行了评估。39例FA病例中，无论肿瘤分期如何，仅发生3例复发和1例死亡，结果与非间变性WT相当。8例诊断时有转移且原发肿瘤为FA的儿童存活且无复发；23例IV期DA WT儿童中有22例死于肿瘤。这一新定义强化了仔细记录每个肿瘤切片确切取材部位的重要性。
