嗜酸细胞性乳头状肾细胞癌的临床病理观察(附2例报告)

CLINICOPATHOLOGIC OBSERVATION OF ONCOCYTIC PAPILLARY RENAL CELL CARCINOMA: A REPORT OF TWO CASES

目的探讨嗜酸细胞性乳头状肾细胞癌(OPRCC)的临床病理特点及鉴别诊断。方法 OPRCC病人2例(男女各1例),年龄分别为67岁和53岁,均因体检发现,均行手术治疗。OPRCC组织标本行苏木精-伊红及免疫组化染色。结果大体观察肿瘤呈圆形或椭圆形,界限清楚,无包膜,切面灰褐色。镜下观察:1例病人肾肿瘤完全由发育较好的纤细的乳头状结构组成,乳头被覆单层立方状胞浆丰富的强嗜酸细胞,核圆形、规则,核仁不明显,FUHRMAN核分级Ⅰ级,局部区域瘤组织出血、囊性变。另1例病人瘤组织主要由密集、大小不等的管状结构组成,部分管腔内可见有或无纤维轴心的乳头状突起;管壁及乳头结构表面均衬覆单层圆形或多边形、胞浆丰富、强嗜酸性的瘤细胞,其中散在胞浆透明空泡状的瘤细胞,瘤细胞核圆形、染色质粗、可见核仁及核内包涵体,FU-HRMAN核分级Ⅳ级。免疫组化染色:2例瘤细胞均呈EMA、CK7和CK18弥漫强阳性;vimentin、AMACR和E-cadherin表达不一;CD10、RCC、CD117和CD68均阴性。结论 OPRCC是乳头状肾细胞癌的罕见组织学亚型,诊断时需与其他具有嗜酸细胞形态的肾肿瘤鉴别。

Objective To discuss the clinicopathological features of oncocytic papillary renal cell carcinoma（OPRCC） and its differential diagnosis.Methods Two cases（one male,67 fears old;one female,53） with OPRCC were identified at medical examination,and underwent surgery.The tissue specimens were stained by HE and immunohistochemistry.Results Macroscopically,the tumors were round or oval in shape,with a clear margin,without envelope,being dust color on the incisal surface.Microscopically： case 1 showed the tumor was entirely composed of well-developed thin mamillae,coating with a single layer of cuboidal oncocytic cells with abundant eosinophilic granular cytoplasm.The nuclei were round and regular with obscure nucleolus（FUHRMAN nuclear grade Ⅰ）,tissue bleeding and cystic change could be seen in local areas;in case 2,the tumor was mainly composed of intensive and inequality-of-size tubiform structure,papillary projections with or without thin vascular cores could be seen intraluminally.The surface of tubal wall and nipples were lined with oncocytic cells of deeply eosinophilic granular cytoplasm.Clear vacuolated cells were scattered among the oncocytic cells.The nuclei of the tumor cells were round,with coarse chromatin,nucleoli and intranuclear inclusion could be found（FUHRMAN nuclear grade Ⅳ）.Immunohistochemically,both cases displayed a strong and diffuse positive for EMA,CK7 and CK18;varying expressions for vimentin,AMACR and E-cadherin;and negative for CD10,RCC,CD117 and CD68.Conclusion Oncocytic is a rare subtype of papillary renal cell carcinoma.At diagnosis,the difference of this condition should be made from other renal tumors that possess oncocytic morphological features.