鼻咽部原发性甲状腺样低级别乳头状腺癌临床病理学特征

Primary thyroid-like low-grade papillary adenocarcinoma of the nasopharynx: a clinicopathological analysis

目的探讨鼻咽部甲状腺样低级别乳头状腺癌(TL-LGNPPA)的临床病理学特点、诊断与鉴别诊断要点。方法报道1例鼻咽部甲状腺样低级别乳头状腺癌的临床及影像学资料,行HE染色、免疫组化标记及分子病理检测,分析其临床病理特征并随访患者预后,以及复习相关文献。结果患者女性,47岁。镜下肿瘤主要由具有纤维血管轴心的树枝状乳头、管状腺体和梭形细胞区构成。腺体不规则,呈囊状或管状,乳头和管腔表面被覆单层或假复层柱状上皮。瘤细胞圆形或卵圆形,核仁不明显,未见核分裂。免疫组化:肿瘤细胞CK7、CK19和TTF-1(+),TG、CD15和CK5/6(-)。原位杂交检测示EBER(-),BRAF基因1799位点15外显子(BRAFV600E)无突变。随访3年,无复发。结论原发性鼻咽部甲状腺样低级别乳头状腺癌是一种非常罕见的低度恶性肿瘤,明确诊断需结合病理组织学形态和免疫表型。

Objective To explore the clinicopathological features,diagnosis and differential diagnosis of thyroid-like lowgrade papillary adenocarcinoma of the nasopharynx. Methods Clinical,radiological,histopathological features and immunophenotypes were analyzed in one case of thyroid-like low-grade papillary adenocarcinoma of the nasopharynx.Related literatures were reviewed. Results The case reported here was a 47-year-old Chinese female. Microscopically,the superficial aspect of the tumor displayed papillary structures with hyalinized brovascular cores,glandular structures and spindle cell component. The neoplastic glands were more irregular,cystic or tubular. They were lined by mildly to moderately pleomorphic columnar and pseudostratied cells. These columnar and spindle cells had round to oval vesicular nuclei with inconspicuous nucleoli and clear chromatin. No mitotic activity was discerned. Immunohistochemically,neoplastic cells（ including the spindle cell component） were diffusely and strongly positive for CK7,CK19,TTF-1 and negative for TG,CD15 and CK5 /6. EBER in situ hybridization was negative. In the molecular genetic study,no mutation were found at position 1799（ exon 15） in the BRAF-gene（ BRAFV600E）. No recurrence was detected in 3 years followup. Conclusions Thyroid-like low-grade papillary adenocarcinoma of the nasopharynx is extremely rare with low grade malignancy. It is important to combine histopathologic features with immunophenotyping.