PO.CL01.20 · 临床研究
免疫组化检测结直肠腺癌中 Napsin A 的表达：一项观察性研究
The expression of Napsin A by immunohistochemistry in colorectal adenocarcinomas: An observational study
该海报暂无可下载的资料
AACR 官方页面
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
背景：
在小活检标本中区分原发性结直肠腺癌与转移性肺腺癌可能具有挑战性，尤其是当肿瘤富含黏液或分化差时。Napsin A 被广泛用作肺腺癌的标志物，然而零星的报道提示它有时可能在非肺原发肿瘤中表达，包括结直肠癌。我们着手研究在我们的环境中 Napsin A 在结直肠腺癌中的表达频率，并评估它可能造成多大的诊断陷阱。
方法：
我们回顾性地使用福尔马林固定石蜡包埋组织块复核了 107 例结直肠腺癌样本。使用多克隆和单克隆抗体进行 Napsin A 免疫组化。三名病理科医生独立复核切片；当至少 1% 的肿瘤细胞中存在颗粒状细胞质染色时，Napsin A 被判定为阳性。对每个病例，我们记录了肿瘤分化、组织学亚型和 CDX2 状态。
结果：
在这 107 例肿瘤中，83 例（77.6%）为中分化，18 例（16.8%）为低分化，6 例（5.6%）为高分化。组织学亚型包括非特指型（84.1%）、黏液型（6.5%）、印戒细胞型（6.5%）及少数其他变异型。所有病例均为 CDX2 阳性，支持结直肠起源。Napsin A 染色仅在 1/107 例（0.9%）低分化印戒细胞腺癌中观察到，且仅限于单克隆抗体；无一例使用多克隆抗体显示阳性。
结论：
在本系列研究中，Napsin A 在结直肠腺癌中的表达并不常见但也并非完全没有。因此，一例 Napsin A 阳性的转移性腺癌仍有可能代表结直肠原发肿瘤，尤其是在不寻常的组织学亚型中。我们的研究结果支持谨慎使用 Napsin A，并始终结合形态学、更广泛的免疫组化组合、临床数据以及在可能情况下的分子检查。更大规模的多中心数据集将有助于阐明其可推广性，以及特定结直肠癌亚型是否更易于表达 Napsin A。
查看英文原文 English abstract
Background:
Distinguishing primary colorectal adenocarcinoma from metastatic pulmonary adenocarcinoma can be challenging in small biopsies, particularly when tumors are mucin-rich or poorly differentiated. Napsin A is widely used as a marker of pulmonary adenocarcinoma, yet scattered reports suggest it may sometimes be expressed in non-pulmonary primaries, including colorectal cancer. We set out to see how often napsin A is expressed in colorectal adenocarcinomas in our setting and to gauge how much of a diagnostic trap it may pose.
Methods:
We retrospectively reviewed 107 colorectal adenocarcinoma samples using formalin-fixed, paraffin-embedded tissue blocks. Napsin A immunohistochemistry was performed using polyclonal and monoclonal antibodies. Three pathologists independently reviewed the slides; napsin A was considered positive when granular cytoplasmic staining was present in at least 1% of tumor cells. For each case, we recorded tumor differentiation, histological subtype, and CDX2 status.
Results:
Of the 107 tumors, 83 (77.6%) were moderately differentiated, 18 (16.8%) poorly differentiated, and 6 (5.6%) well differentiated. Histological subtypes included not otherwise specified (84.1%), mucinous (6.5%), signet ring (6.5%), and a small number of other variants. All cases were CDX2 positive, supporting a colorectal origin. Napsin A staining was observed in only 1/107 cases (0.9%) of poorly differentiated signet-ring adenocarcinoma, confined to the monoclonal antibody; none showed positivity with the polyclonal antibody.
Conclusion:
In this series, napsin A expression in colorectal adenocarcinoma was uncommon but not absent. Thus, a napsin A-positive metastatic adenocarcinoma could still represent a colorectal primary, especially in unusual histological subtypes. Our findings support cautious use of napsin A, always alongside morphology, a broader immunohistochemical panel, clinical data, and, where possible, molecular work-up. A larger multicenter dataset would help clarify generalizability and whether specific colorectal carcinoma subtypes are more prone to napsin A expression.
利益披露 Disclosure
C. Cingo, None..
R. Marima, None..
T. Marutha, None..
Z. Dlamini, None..
B. Mosoane, None.