肾细胞癌中琥珀酸脱氢酶亚单位A和B蛋白的表达缺失

Loss of expression of succinate dehydrogenase subunit A and B in renal cell carcinoma

目的探讨肾细胞癌(RCC)中琥珀酸脱氢酶亚单位A(SDHA)及B(SDHB)的蛋白表达情况及其与临床病理特征之间的关系。方法采用免疫组织化学方法检测179例RCC病例肿瘤组织中这两种蛋白的表达情况及其与该肿瘤临床病理特征之间的关系。结果 179例RCC中,18例SDHA及SDHB表达阴性及可疑阴性,其中SDHA及SDHB均为可疑阴性2例(1.1%)。肿瘤位于左肾12例,右肾6例;高分化组15例(83.3%)、中分化组1例(5.6%)及低分化组2例(11.1%)。大部分SDH阴性及可疑阴性RCC有以下特征:肿瘤内有陷入的正常肾小管,肿瘤细胞为多边形,由菲薄的纤维组织分割成巢,核内染色质呈空泡状,肿瘤细胞胞质内可见嗜酸性絮状物、空泡及嗜酸性包涵体。结论 SDHA和(或)SDHB蛋白表达阴性(缺失)及可疑阴性RCC病例有独特的组织学特征,左肾明显多于右肾,高分化组更常见。

Objective To investigate the expression of succinate dehydrogenase subunit A(SDHA)and subunit B(SDHB)in patients with renal cell carcinoma(RCC),and its relationship with the clinicopathologic characteristics.Methods The expression of SDHA and SDHB was detected in 179 cases of RCC by immunohistochemistry and the relationship between the SDHA,SDHB expression and the clinicopathologic characteristics of RCC were analyzed.Results In 179 cases of RCC,18 cases(10.1%)were shown with negative or suspicious negative expression of SDHA and SDHB,including 2 cases(1.1%)with suspicious-negative expression of SDHA and SDHB.12 cases(66.7%)had tumor located in left kidney and 6 cases(33.3%)had tumor located in right kidney.The well-differentiation group contained 15 cases(83.3%),moderate-differentiation group contained 1 case(5.6%)and poor-differentiation group contained 2 cases(11.1%).Most of SDH negative and suspicious negative RCC had the following characteristics that the normal renal tubule could be seen within the tumor.The tumor was composed of polygonal cells arranged in nest,and the polygonal cells were separated by a fine fibrovascular stroma.The nuclei were shown around with vesicular chromatin.The eosinophilic flocculet material,vacuole and eosinophilic inclusion body could be seen in the cytoplasm of tumor cells.ConclusionThe RCC cases with negative expression of SDHA and SDHB protein have unique histological features,with significantly higher incidence in the left kidney than that in the right kidney.