Fleming K E, Perez-Ordoñez B, Nasser J G, Psooy B, Bullock M J
Department of Pathology (Anatomical Pathology), Capital District Health Authority (QEII Site) and Dalhousie University, 721 Mackenzie Building, 5788 University Ave, Halifax, NS, B3H 1V8, Canada.
Head Neck Pathol. 2012 Sep;6(3):395-9. doi: 10.1007/s12105-012-0339-6. Epub 2012 Mar 6.
Seromucinous hamartoma is a benign lesion of the sinonasal tract. Since its description in 1974, only a small number of additional cases have been reported. It is composed of a proliferation of seromucinous glands and ducts within a variable fibrous stroma. The serous component typically stains positively for S100 (at least focally) and lacks p63 positive abluminal cells. The lack of myoepithelial/basal cells is an important diagnostic feature of seromucinous hamartoma; their absence could lead to an incorrect diagnosis of low-grade sinonasal adenocarcinoma. We report the case of a polypoid mass resected from the posterior nasal cavity and nasopharynx of a 54-year-old woman. The lesion contained a population of small and large glands lined by cuboidal to flattened cells within a hypocellular stroma varying from dense and sclerotic to myxoid. Additionally, there was a superficial focus of ciliated invaginated surface epithelium and glands. Throughout the lesion there were no cytologic or architectural features of malignancy. The histologic features were diagnostic of seromucinous hamartoma. Immunohistochemistry showed focal S100 positivity of the serous glands. However, in contrast to previously reported cases, the glands focally showed an outer basal layer that was calponin, p63 and actin positive. Our case demonstrates two important points. First, complete absence of p63 staining should not necessarily be a required feature in the diagnosis of seromucinous hamartoma. Second, the ciliated larger glands--in keeping with respiratory epithelial adenomatoid hamartoma (REAH)--support the suggestion that seromucinous hamartoma and REAH are a spectrum of lesions, often seen together.
浆液黏液性错构瘤是鼻窦道的一种良性病变。自1974年首次描述以来，仅有少数额外病例被报道。它由浆液黏液性腺和导管在不同的纤维性间质内增生构成。浆液成分通常S100染色阳性（至少局灶性阳性），且缺乏p63阳性的腔外细胞。缺乏肌上皮/基底细胞是浆液黏液性错构瘤的一个重要诊断特征；其缺失可能导致对低级别鼻窦腺癌的误诊。我们报告了一例从一名54岁女性的后鼻腔和鼻咽部切除的息肉样肿物病例。该病变包含一群大小不等的腺体，内衬立方状至扁平状细胞，位于细胞稀少的间质内，间质从致密硬化到黏液样不等。此外，有一处浅表的纤毛内陷表面上皮和腺体。整个病变中没有恶性的细胞学或结构特征。组织学特征诊断为浆液黏液性错构瘤。免疫组化显示浆液性腺局灶性S100阳性。然而，与先前报道的病例不同，这些腺体局灶性显示外层基底层calponin、p63和肌动蛋白阳性。我们的病例说明了两个要点。第一，在浆液黏液性错构瘤的诊断中，完全缺乏p63染色不一定是必需特征。第二，有纤毛的较大腺体——与呼吸道上皮腺瘤样错构瘤（REAH）一致——支持了浆液黏液性错构瘤和REAH是一系列病变、常一起出现的观点。
