Department of Pathology, All India Institute of Medical Sciences, New Delhi, India.
Department of Pulmonary Medicine and Sleep Disorders, All India Institute of Medical Sciences, New Delhi, India.
Cancer Cytopathol. 2021 Jan;129(1):53-61. doi: 10.1002/cncy.22342. Epub 2020 Aug 17.
NUT carcinoma (NC) is an aggressive neoplasm that often presents with alarge tumor burden and metastases; cytology is frequently one of the primary diagnostic modalities. Primary pulmonary NCs are very rare and cytology descriptions are limited. The current study was performed to analyze the cytomorphological features of primary pulmonary NCs in different cytology samples and preparations.
A total of 15 cytology specimens from 10 patients with primary pulmonary NCs diagnosed primarily on histology were retrieved and reviewed.
Fifteen cytology samples, including aspirates from primary (5 samples) and metastatic (5 samples) sites, sputum (1 sample), and effusions (4 samples), that were prepared as direct smears, centrifuged smears, and cell blocks were reviewed. Aspirate smears from all cases were cellular and demonstrated fragments and cohesive clusters of primitive tumor cells with scant cytoplasm, ovoid nuclei with coarse granular chromatin, and consistently conspicuous single nucleoli in a frequently neutrophil-rich necrotic background with dispersed bare tumor nuclei. In fluid cytology, tight, 3-dimensional tumor clusters and singly lying tumor cells were observed. Squamous differentiation in the form of sheets and singly lying polygonal tumor cells with abundant dense cytoplasm was noted focally in rare cases. The diagnoses during original sign-outs were poorly differentiated carcinoma, poorly differentiated squamous cell carcinoma, and malignant small round cell tumor. NUT-1 (NUT family member 1 protein) immunocytochemistry performed on cell blocks demonstrated characteristic speckled nuclear staining in tumor cells.
Pulmonary NC presents as a poorly differentiated carcinoma with focal to absent squamous differentiation on cytology. Cellular fragments of primitive tumor cells with conspicuous nucleoli should raise suspicion of NUT carcinoma and prompt ancillary testing.
神经内分泌肿瘤（NC）是一种侵袭性肿瘤，常表现为大肿瘤负荷和转移；细胞学检查通常是主要的诊断方式之一。原发性肺 NC 非常罕见，细胞学描述有限。本研究旨在分析不同细胞学标本和制备物中原发性肺 NC 的细胞形态学特征。
共回顾了 10 例经组织学诊断为原发性肺 NC 的患者的 15 例细胞学标本。
共回顾了 15 例细胞学标本，包括原发性（5 例）和转移性（5 例）部位的抽吸物、痰（1 例）和积液（4 例），分别制备为直接涂片、离心涂片和细胞块。所有病例的抽吸涂片均为细胞性，显示出原始肿瘤细胞的碎片和黏附性簇，细胞质稀少，卵圆形核，粗颗粒状染色质，单个核仁明显，常伴有富含中性粒细胞的坏死背景，散布着裸肿瘤核。在液体细胞学中，观察到紧密的 3 维肿瘤簇和单独存在的肿瘤细胞。偶尔在少数情况下，观察到以片状和单独存在的多边形肿瘤细胞形式出现的鳞状分化，细胞质丰富且密集。最初报告的诊断为低分化癌、低分化鳞状细胞癌和恶性小圆细胞肿瘤。细胞块上进行的 NUT-1（NUT 家族成员 1 蛋白）免疫细胞化学显示肿瘤细胞有特征性的斑点状核染色。
肺 NC 在细胞学上表现为低分化癌，伴有局灶性至无鳞状分化。具有明显核仁的原始肿瘤细胞的细胞碎片应引起对 NUT 癌的怀疑，并提示辅助检测。
