鼻咽乳头状腺癌4例临床病理分析

Clinicopathological findings of nasopharyngeal papillary adenocarcinoma:report of four cases

目的分析鼻咽乳头状腺癌的临床病理特点,加深对该肿瘤的认识。方法回顾性分析4例鼻咽乳头状腺癌的临床病理资料,并随访患者预后情况。结果 4例中男性2例,女性2例,年龄32~69岁,中位年龄46岁。其中3例分别表现为鼻腔不适、间断性鼻腔出血及涕中带血。2例肿物位于鼻咽,1例累及鼻咽及鼻中隔后端,1例位于鼻中隔后端。镜下,4例肿瘤均以乳头状结构为主,也可见腺体结构,3例肿瘤可见梭形细胞成分。4例中3例可见肿瘤与黏膜被覆上皮相移行,1例可见砂砾体,1例可见鳞化。肿瘤细胞胞质中等量,轻度嗜酸。细胞核呈圆形、卵圆形,梭形细胞区细胞核呈梭形。细胞核显示轻度至多中度的异型性,无核仁或见不明显小核仁。核染色质细或略粗,分布均匀,或呈空泡状。核分裂象罕见,仅1例肿瘤表面见糜烂、坏死。免疫组化:4例肿瘤CK和vimentin均弥漫(+),3例TTF-1弥漫(+),TG、BRAF、napsin A、GFAP和CDX-2均(-)。Ki-67标记指数为1%~2%,局灶略高可达3%~5%。肿瘤行EBER(EB病毒编码的小RNA)原位杂交检测,4例均为(-)。随访3例,随访时间6~40个月,1例于术后14个月复发,3例均未发现转移。结论鼻咽乳头状腺癌是好发于鼻咽部的一种低级别恶性肿瘤,除鼻咽部外该肿瘤也可发生于鼻中隔尤其是鼻中隔后端。除乳头和腺体结构,鼻咽乳头状腺癌也常见梭形细胞成分。免疫组化学染色TTF-1(+)是诊断鼻咽乳头状腺癌的重要线索,但不是诊断该肿瘤的必要条件。对鼻咽部及鼻中隔具有乳头状结构的肿瘤进行诊断时应考虑到该肿瘤。

Objective To analyze the clinicopathological features of nasopharyngeal papillary adenocarcinoma to deepen understanding of this neoplasm. Methods The clinicopathological data of 4 cases of nasopharyngeal papillary adenocarcinoma were retrospectively analyzed. Follow-up information for 3 patients was obtained. Results There were 2 males and 2 females,ranging in age from 32 to 69 years（ median,46 years）. 3 cases presented with nasal discomfort,intermittent epistaxis and snot with blood,respectively. Two cases of the tumor were located in the nasopharynx,one case involved nasopharynx and posterior nasal septum,and one case was located in the posterior nasal septum. Histologically,all tumors revealed a predominant growth pattern of papillary architecture,and tubular architecture was also observed.There were spindle cell components in 3 cases. Transition from mucosal surface epithelium to tumor cells was identified in3 cases. Psammoma bodies were seen in one of the 4 cases. Squamous metaplasia was seen in one case. The neoplastic cells had moderate amount and mildly eosinophilic cytoplasm. The nuclei were round to oval,and were spindle in the spindle cell components. The nuclei showed mild to at most moderate nuclear atypia,without or with tiny nucleoli.Chromatin of the nuclei was fine or slightly coarse,evenly distributed,vesicular nuclei could also be observed. Mitotic figures were rare,and necrosis was observed only in one case. Immunohistochemically,the tumor cells of the 4 cases were all diffusely positive for cytokeratin（ 4/4,100%） and vimentin（ 4/4,100%）,but were all negative for thyroglobulin,BRAF,Napsin A,GFAP and CDX-2. TTF-1 expressed in only 3 cases of tumor（ 3/4,75%）. The Ki-67 labelling index（ MIB-1 index） was about 1-2%,and reached 3-5% in the most hot spot. EBV was detected by EBER ISH,and all cases were negative. Three patients were followed up for 6 to 40 months： one case recurred 14 months after removal of the tumor and no patient showed metastasis. Conclusions Papillary adenocarcinoma of nasopharynx is a low grade malignant neoplasm generally originated in the nasopharynx. In addition to the nasopharynx,the tumor can also occur in the nasal septum,especially in the posterior nasal septum. In addition to papillary and glandular structures,spindle cell components are also commonly observed in nasopharyngeal papillary carcinoma. Immunohistochemical expression of TTF-1 is an important diagnostic clue of nasopharyngeal papillary adenocarcinoma,but it is not essential for a confirming diagnosis of this tumor. Pathologists should consider this tumor when making the diagnosis and differential diagnosis of the nasopharyngeal and nasal septum neoplasms with papillary structures.