Department of Pathology, McGill University Faculty of Medicine, Montreal, Quebec, Canada
Department of Diagnostic and Molecular Pathology, McGill University Medical Centre, Montreal, Quebec, Canada.
BMJ Case Rep. 2024 Apr 2;17(4):e259538. doi: 10.1136/bcr-2023-259538.
We report a young pregnant woman with large midline thoracic mass and markedly elevated serum alpha-fetoprotein (AFP) levels. Initially suspected as a germ cell tumour (GCT) due to age, site, and high AFP levels, a biopsy unveiled a high-grade malignant tumour characterised by undifferentiated monotonous cells. Although tumour cells exhibited positive AFP, the overall immunoprofile did not provide additional evidence to support GCT. Further work-up showed positive for NUT (nuclear protein in testis) immunostaining and the presence of BRD4-NUT1 fusion, confirming the diagnosis of NUT carcinoma. On radiology, there were extensive metastases to lungs, liver, vertebrae, and placenta. Despite aggressive chemotherapy, radiotherapy and immunotherapy, she did not respond to the therapies. Fortunately, her child was not affected by the carcinoma. This is the first case highlighting that thoracic lung primary NUT carcinoma can spread to the placenta and manifest with elevated serum AFP levels, potentially leading to misdiagnosis as GCT both clinically and pathologically.
我们报告了一例年轻孕妇，其胸部中线有巨大肿块，血清甲胎蛋白 (AFP) 水平显著升高。由于年龄、部位和高 AFP 水平，最初怀疑为生殖细胞肿瘤 (GCT)，但活检显示为高级别恶性肿瘤，其特征为未分化的单调细胞。虽然肿瘤细胞 AFP 阳性，但整体免疫组化结果并未提供更多证据支持 GCT。进一步检查显示核蛋白在睾丸 (NUT) 免疫染色阳性，存在 BRD4-NUT1 融合，确诊为 NUT 癌。影像学显示肺部、肝脏、椎体和胎盘广泛转移。尽管进行了积极的化疗、放疗和免疫治疗，但她的病情并未得到缓解。幸运的是，她的孩子未受该癌影响。这是首例强调胸肺部原发性 NUT 癌可播散至胎盘并表现出血清 AFP 水平升高的病例，这可能导致临床上和病理上误诊为 GCT。
