Department of Pathology & Medicine, Houston Methodist Hospital, Houston, TX, USA.
Histopathology Department, Royal Surrey Hospital, Guildford, Surrey, UK.
Head Neck Pathol. 2021 Jun;15(2):642-648. doi: 10.1007/s12105-020-01199-z. Epub 2020 Jul 13.
Tumor-to-tumor metastasis (TTM) is a rare, but well-described phenomenon occurring in patients with multiple synchronous or metachronous primary malignancies. Olfactory neuroblastoma (ONB) is a rare malignant, neuroectodermal sinonasal tract tumor that occurs within the ethmoid sinus involving the cribriform plate. Very few cases of ONB have been documented to metastasize to other primary malignancies, but the reverse scenario is exceptional. During an evaluation for anosmia, a right nasal polyp was identified on imaging and endoscopy in a 66-year-old woman, with a polypectomy performed. Histologic examination showed classical features of a low-grade olfactory neuroblastoma, but within the tumor were isolated epithelioid cells which were strongly pancytokeratin immunoreactive. Review of the clinical history revealed lobular breast carcinoma treated 10 years earlier. Further evaluation with immunohistochemistry showed strong and diffuse nuclear estrogen and progesterone receptor reactivity, along with GATA3. These results confirmed TTM of an invasive lobular breast carcinoma to ONB. By employing a limited immunohistochemistry panel for all small round blue cell tumors that includes pancytokeratin, p40, S100 protein, SOX10, synaptophysin, desmin, CD99, and CD45, one is able to more accurately diagnose the classical tumor types, while also showing potentially unusual tumor features or exceptionally rare events like metastatic lobular breast carcinoma to ONB.
肿瘤对肿瘤转移（TTM）是一种罕见但已有充分描述的现象，发生于同时或异时存在多种原发性恶性肿瘤的患者。嗅神经母细胞瘤（ONB）是一种罕见的恶性神经外胚层鼻腔鼻窦肿瘤，发生于筛窦并累及筛板。ONB 转移至其他原发性恶性肿瘤的病例非常少见，但相反的情况则较为罕见。在对嗅觉丧失进行评估时，一名 66 岁女性的影像学和内镜检查发现右侧鼻腔息肉，行息肉切除术。组织学检查显示出典型的低级别嗅神经母细胞瘤特征，但肿瘤内存在孤立的上皮样细胞，对广谱细胞角蛋白呈强阳性反应。回顾临床病史，发现曾于 10 年前接受过乳腺小叶癌治疗。进一步的免疫组织化学检查显示强而弥漫的核雌激素和孕激素受体反应性，以及 GATA3。这些结果证实了乳腺小叶癌向 ONB 的 TTM。通过对所有小圆蓝细胞肿瘤采用包括广谱细胞角蛋白、p40、S100 蛋白、SOX10、突触素、结蛋白、CD99 和 CD45 的有限免疫组化组合，可以更准确地诊断出经典的肿瘤类型，同时还可以显示出潜在的不寻常的肿瘤特征或罕见的事件，如转移性乳腺小叶癌向 ONB。
