CD117阳性小肠间质瘤中Ki67和p53蛋白的表达及在预后中的意义

Prognostic significance of Ki67 and p53 protein in small bowel stromal tumor immunopositive for CD117

目的 :研究小肠间质瘤 (smallbowelstromaltumors,SBST)Ki6 7和p5 3免疫组织化学的表达 ,探讨两者在肿瘤良恶性划分和预后中的作用。方法 :选用CD117阳性的SBST 33例进行光镜观察 ,用EnVisionTM+二步法免疫组化方法检测Ki6 7和 p5 3蛋白在肿瘤中的表达情况并与形态学进行比较。 结果 :33例SBST患者 ,男 2 0例 ,女13例 ,年龄 2 1～ 71岁 ,发生于十二指肠 5例 ,空肠 2 2例 ,回肠 6例。肿瘤最大径的范围在 1.5～ 2 0cm之间。在光镜下出现肿瘤内坏死的有 11例。肿瘤核分裂象计数每 5 0个高倍镜视野 0个有 6例 ,1～ 2个 5例 ,≥ 3个的有 2 2例。 33例中良性 4例 ,交界性 4例 ,恶性 2 5例。随访时间为 3～ 180个月 (平均 73.3个月 ) ,结果为良性组 4例均无瘤生存 ;交界性组 2例无瘤生存 ,1例失访 ,1例在无瘤生存 18个月后失访 ;恶性组无瘤生存有 7例 ,带瘤生存者及死亡有 16例 ,2例失访。Ki6 7染色阴性 2例 ,均为良性 ;其余 31例阳性中 ,增殖指数 (阳性细胞数 )大于 5 %的有恶性 16例 (94 .1% ) ,交界性 1例。在免疫组化p5 3染色中 ,恶性组 2 5例均呈阳性表达 (平均阳性细胞数 4 2 .9% ) ,其中 12例阳性细胞数大于 5 0 %。当Ki6 7和 p5 3均为阴性或两者阳性细胞数分别是 <1%和 <10 %时 ,肿瘤呈良性经过 ,预后?

Objective: To investigate the correlative factors of the prognosis by observing the immunohistochemical features of small bowel stromal tumors(SBST). Methods: Thirty three cases of stromal tumors with expressed CD117 were examined by the light microscope. The expressions of Ki67and p53 protein with EnVision TM + staining were detected in the tumors and compared with the morphology. Results: The group included 20 males and 13 females whose ages ranged from 21 to 71 years ( median: 46 years ); the tumors were situated in duodenum (5 cases), jejunum (22 cases) and ileum (6 cases). Grossly, tumors size was from 1.5 to 20 cm. In eleven cases tumors showed foci of tumor cell necroses.In all these cases, mitotic counts ranged from 0 to 62 mitotic figures per 50 HPF(high power fields),six of 33 tumors had no mitotic figures per 50 HPF ,5 cases had 1 2 mitotic figures and 22 cases had ≥3 mitotic figures. Histologically,4 cases classified as benign, 4 cases as border line and 25 cases as malignant. Follow up of 7 cases with benign and borderline tumors were alive without tumor. In the malignant group of 23 cases, 6 patients died of disease,10 patients were alive with evidence of metastatic disease, and 7 patients were alive without tumor. Immunohistochemically, 31 of 33 stromal tumors were positive for Ki67, 16 cases of malignant tumors showed significant staining (>5% cells ). 31 of 33 tumors were positive for p53 protein, and all the 25 (100%) malignant tumors showed staining. In 12 of the 25 cases ,the staining was strong and diffuse(>50% cells ). When the Ki67 and p53 proteins were negative or showed focal expressions ( Ki67<1% and p53<10% ), the patients presented a good prognosis. And when there were strong expressions ( Ki67 >5% and p53 >50% ), the patients portended a poor prognosis. Conclusion: Immunohistochemical analysis of Ki67 and p53 protein was a better method in the prognosis. When Ki67 showed strong position, it was a bad sign. When p53 protein showed strong position, it might be the potential malignant parameter. When Ki67 and p53 proteins were all strong expressions, these patients portended a poor prognosis. In addition to the invasion and metastasis, tumor size, mitotic counts and tumor cell necrosis were also helpful parameters for diagnosis of malignancy.