Department of Histopathology, The Christie NHS Foundation Trust, Wilmslow Road, Manchester, UK.
Am J Surg Pathol. 2012 Jun;36(6):895-9. doi: 10.1097/PAS.0b013e3182498f2b.
Distinguishing between lung adenocarcinoma and squamous cell carcinoma is becoming increasingly important, given the different treatment regimens available. Although histologic subdivision between the two is generally not difficult in differentiated tumors, it can be challenging in poorly differentiated tumors and may require a panel of immunohistochemistry stains. The p63 gene encodes two different N-termini (TA and ΔN). ΔNp63 is selectively expressed in squamous cell carcinoma, whereas TAp63 is not restricted only to it. 4A4, a widely used anti-p63 antibody, identifies both isoforms and is expressed in about 15% of adenocarcinomas, and, although generally focal, its expression can be diffuse. In this study, a total of 150 lung adenocarcinomas and 50 squamous cell carcinomas were immunostained by antibodies for p63 (4A4), ΔNp63 (p40), and TTF-1 (8G7G3/1). Twenty-seven adenocarcinomas (18%) were positive for p63 to a variable extent, with diffuse reaction being seen in 13 tumors (8.7%). p63 expression was seen in all subtypes of adenocarcinomas, except for the mucinous type. p40 was negative in all adenocarcinomas. All squamous cell carcinomas were diffusely positive for both p63 and p40. Four of 27 p63-positive adenocarcinomas were negative for TTF-1. p63 expression is not uncommonly seen in adenocarcinomas, whereas ΔNp63 (p40) expression is specific for squamous cell carcinoma, with sensitivity comparable to that of p63 expression. Presence of p63-positive cells in poorly differentiated lung adenocarcinoma may be erroneously interpreted as evidence of squamous cell differentiation. p40 appears to be a more reliable marker for squamous cell carcinoma.
区分肺腺癌和鳞状细胞癌变得越来越重要，因为这两种癌症有不同的治疗方案。虽然在分化良好的肿瘤中，组织学细分通常不难，但在分化不良的肿瘤中可能具有挑战性，并且可能需要一组免疫组织化学染色。p63 基因编码两个不同的 N 端（TA 和 ΔN）。ΔNp63 选择性表达于鳞状细胞癌，而 TAp63 不仅限于此。4A4 是一种广泛使用的抗 p63 抗体，可识别两种同工型，在约 15%的腺癌中表达，虽然通常是局灶性的，但它的表达可以是弥漫性的。在这项研究中，总共对 150 例肺腺癌和 50 例鳞状细胞癌进行了 p63（4A4）、ΔNp63（p40）和 TTF-1（8G7G3/1）抗体的免疫染色。27 例腺癌（18%）p63 表达程度不同，13 例肿瘤（8.7%）出现弥漫性反应。p63 表达见于除黏液型以外的所有腺癌亚型。所有腺癌均为 p40 阴性。所有鳞状细胞癌均弥漫性表达 p63 和 p40。27 例 p63 阳性腺癌中有 4 例 TTF-1 阴性。p63 表达在腺癌中并不罕见，而 ΔNp63（p40）表达特异性强于鳞状细胞癌，与 p63 表达的敏感性相当。在低分化肺腺癌中出现 p63 阳性细胞可能会被错误地解释为鳞状细胞分化的证据。p40 似乎是鳞状细胞癌更可靠的标志物。
