Department of Pathology, Baylor Scott and White Health, 2401 S 31st St, Temple, TX, USA.
Head Neck Pathol. 2021 Jun;15(2):709-714. doi: 10.1007/s12105-020-01224-1. Epub 2020 Sep 16.
Angiomyolipoma (AML) is a mesenchymal tumor commonly found in the kidneys. Extra-renal AML is uncommon and especially rare in the nasal cavity. To our knowledge, fewer than five cases of nasal AML are reported in the United States. We present a case of nasal AML in a 65-year-old man with a history of rhinosinusitis and obstruction of the left nasal cavity. The lesion comprised of admixed spindled smooth muscle cells, mature adipose tissue, and thick-walled blood vessels. Smooth muscle differentiation of the spindled cells was confirmed by expression of smooth muscle actin. Surprisingly, melanocytic markers, such as HMB45, were negative. The histologic features and immunoprofile suggest that nasal AML is pathologically distinct from neoplastic AMLs/perivascular epithelioid cell tumors (PEComas) that typically occur in the kidney. We propose that nasal AML is a hamartomatous lesion rather than neoplastic. Although AML is rare in the nasal cavity, it should be considered in the differential diagnosis of clinically benign nasal masses.
血管平滑肌脂肪瘤（AML）是一种常见于肾脏的间叶性肿瘤。肾外 AML 并不常见，尤其在鼻腔中更为罕见。据我们所知，在美国报道的鼻腔 AML 病例少于 5 例。我们报告了一例 65 岁男性的鼻腔 AML 病例，该患者有鼻窦炎和左鼻腔阻塞病史。病变由混合的梭形平滑肌细胞、成熟脂肪组织和厚壁血管组成。梭形细胞的平滑肌分化通过平滑肌肌动蛋白的表达得到确认。令人惊讶的是，黑色素细胞标志物，如 HMB45，呈阴性。组织学特征和免疫表型表明，鼻腔 AML 在病理学上与通常发生在肾脏的肿瘤性 AML/血管周上皮样细胞瘤（PEComa）不同。我们提出鼻腔 AML 是一种错构瘤性病变，而非肿瘤性。尽管 AML 在鼻腔中罕见，但在临床上良性鼻腔肿块的鉴别诊断中应考虑到它。
