小胃肠间质瘤临床病理特征及预后48例分析

Clinicopathological Features and Prognosis of 48 Cases with Small Gastrointestinal Stromal Tumor

[目的]探讨小胃肠间质瘤(gastrointestinal stromal tumor,GIST)临床病理特征及预后。[方法]回顾性分析48例小GIST临床病理资料,分析患者预后,ROC曲线分析以确定预测恶性潜能的最佳肿瘤直径。[结果]48例小GIST患者,男性20例,女性28例;中位年龄63岁。临床表现以腹痛(31.25%)和无明显症状(25.00%)为主,好发于胃部(87.50%),其中21例合并其他恶性肿瘤。46例(95.83%)为梭形细胞型,1例为上皮细胞型,1例为混合细胞型。44例(91.67%)核分裂计数≤5/5 mm2,20例为中度或重度异型性,分别在1例、5例患者中检测到坏死、钙化灶。44例极低危险度,3例中危危险度,1例高危危险度。其中9例行基因检测,以C-KIT外显子11(W557-K558)缺失突变常见。相关性分析显示有丝分裂计数与肿瘤大小之间呈正相关(r=0.425,P=0.0026)。ROC曲线分析提示0.75 cm是预测恶性效能最佳的肿瘤直径(曲线下面积为0.82,95%CI:0.714~0.943)。中位随访27个月后,1例患者局部复发,未见远处转移。[结论]小GIST多见于中老年人,最常见于胃,临床症状不典型,发病具有隐匿性。小GIST多为梭形细胞型,绝大部分表现为较低的核分裂计数,直径小于1 cm的间质瘤具有较低的恶性潜能。肿瘤大小和有丝分裂计数是影响小GIST预后的两个重要因素。肿瘤直径大于0.75 cm者应观察更积极。

[Objective]To analyze the clinicopathologic features and prognosis of small gastrointestinal stromal tumor(GIST).[Methods]The clinicopathologic data of 48 cases with small GIST were analyzed retrospectively.ROC curve was used to determine the tumor diameter for predicting malignant potential.[Results]There were 20 males and 28 females with a median age of 63 years.The main clinical manifestation was abdominal pain(31.25%)and 25.00%patients had no obvious symptoms.Most of tumors(87.50%)were located in the stomach,among which 21 cases were complicated with other malignant tumor.Pathologically 46 cases were spindle cell type(95.83%),1 case was epithelial cell type and 1 case was mixed cell type.Nuclear fission were≤5/5 mm2 were observed in 44 cases(91.67%),and moderately or severely heterotropic were in 20 cases.Necrotic and calcification foci were detected in 1 and 5 patients,respectively.There were 44 cases of very low risk,3 cases of medium risk and 1 case of high risk.The deletion mutation of C-KIT exon 11(W557-K558)was common in 9 cases.Pearson correlation analysis show that mitotic count was positively correlated with tumor size(r=0.425,P=0.0026).The area under ROC curve of tumor diameter of 0.75 cm for predicting malignant potential was 0.82(95%CI:0.714~0.943,P<0.01).After a median follow-up of 27 months,1 patient had local recurrence and no distant metastasis.[Conclusion]Small GIST occurs mostly in middle-aged and elderly people,most commonly in the stomach.The clinical symptoms are not typical and the onset is hidden.Most small GIST is spindle cell types,and most of them show a low nuclear fission.Tumor size and mitotic count are two important factors affecting prognosis of small GIST.Tumor diameter larger than 0.75 cm should be observed more actively.