伴发于直肠腺癌的肛周佩吉特病

目的 探讨伴发直肠腺癌的肛周佩吉特病(Paget’s disease)的临床病理学特征、组织学发生及特点。方法 对3例伴发直肠腺癌的肛周佩吉特病进行临床病理学分析,作过碘酸雪夫(PAS)、阿辛蓝和黏液卡红染色,采用免疫组织化学EnVision法行癌胚抗原(CEA)、CK7、CK8、CK10／13、CK20和巨囊性病液体蛋白15(GCDFP15)标记。结果 3例均发生于中老年男性,因便血和(或)大便习惯改变就诊。肛指检查显示距肛1．8～2．0cm处可触及溃疡型或菜花状肿块,3例中2例肛周皮肤伴有湿疹样改变,1例呈细颗粒状。术后标本显示直肠肿瘤位于齿状线上方或紧邻齿状线,组织学上为中分化腺癌(2例)或低分化腺癌(1例)。肛周皮肤内佩吉特细胞主要有两种形态,一种为经典型(A型),另一种为印戒型(B型),两种类型细胞可存在于同一病例中。直肠腺癌细胞和皮肤佩吉特细胞PAS、AB和黏液卡红染色均为强阳性,PAS和AB染色耐淀粉酶消化,并同时表达癌胚抗原、CK7、CK8和CK20标记,而CK10／13和GCDFP15标记均为阴性。结论免疫表型为CK20^ -GCDFP15^-的肛周皮肤佩吉特细胞由结直肠腺癌细胞扩散到表皮内所致。此型肛周皮肤佩吉特病伴结直肠腺癌的概率可高达60％,较发生于其他部位的乳腺外佩吉特病高,提示一旦发现肛周佩吉特病,需注意是否有结直肠癌原发病灶存在的可能性。

A clinicopathological study of perianal Paget's disease associated with internal rectal adenocarcinoma

OBJECTIVE: To investigate the clinicopathological features and the immunohistochemical phenotype of perianal Paget's disease (PPD) associated with internal anorectal adenocarcinoma, with emphasis on the histogenesis of Paget's cells. METHODS: The clinical and pathologic features of three cases of PPD with rectal adenocarcinoma were investigated. Periodic-acid-Schiff (PAS), alcian-blue and mucicarmine staining with and without diastase digestion were performed. The immunohistochemical study was performed on selected sections by a panel of antibodies including carcinoembryonic antigen (CEA), CK7, CK8, CK10/13, CK20 and gross cystic disease fluid protein 15 (GCDFP15). RESULTS: All three cases occurred in middle to old age male patients complaining of anal bleeding. Digital physical examination revealed ulcerated or cauliflower-like masses in the anus just distal to the dentate line. Perianal skin erythematous patches were found in two cases, and small discrete granules in one case. Histologically, the anorectal neoplasm was either a moderately or poorly differentiated adenocarcinoma. Two types of Paget's cells were noted, namely the classical type characterized by a polygonal shape with vesicular nuclei and abundant pale cytoplasm, and the signet ring type characterized by eccentrically displaced nucleus. Both the rectal adenocarcinoma cells and Paget's cells showed strong positivity for PAS, AB and mucicarmine, which were resistant to the diastase digestion. Immunohistochemically, they were both positive for CEA, CK7, CK8 and CK20, but negative for CK10/13 and GCDFP15. CONCLUSIONS: The CK20(+)-GCDFP15(-) type Paget's cells in PPD were derived from the direct intraepithelial Pagetoid spread of anorectal adenocarcinomas. PPD was more frequently associated with internal carcinomas than any other type of extramammary Paget's disease. It is recommended that clinicians should carefully examine the anus or rectum in the presence of PPD to ascertain if it is associated with an internal carcinoma.