核蛋白睾丸 (NUT) 癌 (NC) 是一种罕见且高度侵袭性的肿瘤，其特征是核蛋白睾丸家族成员 1 (NUTM1) 基因（也称为 NUT 基因）的染色体重排。 NC主要发生在头颈部、纵隔和肺部。一般来说，口腔原发性NC极为罕见，且有零星报道。 共收集10家医院福尔马林固定石蜡包埋的低分化口腔和口咽肿瘤标本111例。对这些样本进行NUT蛋白IHC染色，并对NUT IHC阳性病例进一步进行荧光原位杂交（FISH）和RNA测序检测。5例检测到肿瘤细胞中NUT蛋白的表达（其中5例）。 111, 4.5%）。这些病例中的肿瘤位于口底、唇、舌根、牙龈和硬腭。 FISH 检测结果显示 3 名患者出现 BRD4::NUT 重排，2 名患者出现非 BRD4::NUT 重排模式。 RNA测序结果证实了两例BRD4::NUT重排。据我们所知，这是第一个也是最大的口腔NC回顾性研究，我们发现NC很容易被误诊为低分化口腔鳞状细胞癌（SCC）或低分化癌。 4例NC病例的形态和免疫表型与SCC相似，其中3例观察到突然角化。因此，有必要检测NUT蛋白以用于具有这些形态的口腔恶性肿瘤的NC筛查，特别是对于更容易被误诊为其他类型癌症的年轻患者。© 2024 John Wiley

Nuclear protein testis (NUT) carcinoma (NC) is a rare and highly aggressive tumour characterised by chromosomal rearrangement of the nuclear protein testis family member 1 (NUTM1) gene, also known as the NUT gene. NC occurs mainly in the head and neck, mediastinum and lung. In general, primary NC in the oral cavity is extremely rare and reported sporadically.A total of 111 formalin-fixed and paraffin-embedded specimens of poorly differentiated oral and oropharyngeal tumours were collected from 10 hospitals. NUT protein IHC staining was performed on these samples, and fluorescence in-situ hybridisation (FISH) and RNA sequencing detection were further carried out for NUT IHC-positive cases.The expression of NUT protein in tumour cells was detected in five cases (five of 111, 4.5%). The tumours in these cases were located in the oral floor, lip, base of the tongue, gingiva and hard palate. FISH detection results showed BRD4::NUT rearrangement in three patients and a non-BRD4::NUT rearrangement pattern in two patients. RNA sequencing results confirmed BRD4::NUT rearrangement in two cases.To our knowledge, this is the first and largest retrospective study of oral NC, and we found that NC is easily misdiagnosed as poorly differentiated oral squamous cell carcinoma (SCC) or poorly differentiated carcinoma. The morphology and immunophenotype of four NC cases were similar to SCC, and abrupt keratinisation was observed in three cases. Therefore, it is necessary to detect NUT protein for NC screening in oral malignant tumours with these morphologies, especially for young patients who are more likely to be misdiagnosed with other types of cancer.© 2024 John Wiley & Sons Ltd.