野生型胃肠间质瘤的临床病理特征及预后分析

Clinicopathological features and prognosis of 50 cases of wild-type gastrointestinal stromal tumor

目的:探讨野生型胃肠间质瘤(wild-type gastrointestinal stromal tumor,WTGIST)的临床诊治、临床病理特征及预后影响因素,以期为WT-GIST的诊疗提供数据参考。方法:连续收集2005年9月至2021年5月于北京大学人民医院胃肠外科就诊的,经术前穿刺或手术切除标本基因检测明确诊断的50例WT-GIST患者的临床病理资料,进行回顾性分析。结果:50例WT-GIST患者中,男性有25例,女性有25例,中位确诊年龄为57岁(范围:29~87岁);28例患者就诊时具有相关临床表现,5例患者初诊时即伴有远处转移;46例患者接受手术治疗,其中8例发生术前或术中的肿瘤破裂;根据肿瘤发生部位划分,发生于胃的患者有25例,发生于小肠的患者有11例,发生于结直肠的患者有14例;肿瘤平均最大直径为(5.98±3.90)cm(直径范围:0.5~15.0 cm),核分裂象平均数为(5.44±5.21)/50个高倍视野(high-power field,HPF)(核分裂象计数范围:0/50 HPF~19/50 HPF),中位Ki-67指数为8%+(Ki-67指数范围:0%+~79%+);免疫组织化学染色实验中,CD117阳性率为80%,DOG-1(discovered on GIST 1)阳性率为81.25%;50例患者中有23例接受了二代测序(next generation sequencing,NGS)检测,其中有6例检测到可能有意义的基因突变;所有患者的中位随访时间为38.5个月(随访时间范围:2~191个月),1、3和5年无进展生存率分别为77.6%、67.9%和67.9%,1、3和5年总生存率分别为91.9%、78.4%和78.4%;单因素分析结果显示:性别、有无临床表现、有无远处转移、肿瘤最大直径、核分裂象、肿瘤破裂及美国国立卫生研究院(National Institutes of Health,NIH)分级对无进展生存率和总生存率有影响,差异有统计学意义(P<0.05),多因素生存分析显示远处转移、核分裂象和肿瘤破裂是远期预后的独立影响因素。结论:WT-GIST在流行病学、临床诊治和临床病理特征等方面存在一定特殊性。远处转移、核分裂象和肿瘤破裂是WT-GIST患者长期生存的独立影响因素,其他预后因子的对WT-GIST患者生存率的影响还需进一步进行更大样本量的研究来评估。

Objective:To provide more reference for the diagnosis and treatment of wild-type gastroin-testinal stromal tumor(WT-GIST)by investigating the clinical diagnosis and treatment,clinico-pathological features and prognostic factors of WT-GIST.Methods:The clinical diagnosis and treatment,clinicopathological features and prognostic factors of 50 WT-GIST patients admitted to Department of Gastrointestinal Surgery of Peking University People's Hospital from September 2005 to May 2021,who were confirmed by gene testing with preoperative biopsy or surgical resection specimen's,were analyzed retrospectively.Results:In the 50 WT-GIST patients,there were 25 males and 25 females,the median age of diagnosis was 57 years(range of age:29-87 years).Twenty-eight patients presented relevant clinical manifestations,and 5 patients were accompanied with distant metastasis at initial diagnosis.Forty-six patients received surgical treatment,including 8 patients with preoperative or intraoperative tumor rupture.As for the origins of the tumor,25 cases arose from the stomach,11 cases arose from the intestine and 14 cases arose from the colorectum.The mean maximum diameter of the tumor was(5.98±3.90)cm(range of maximum tumor diameter:0.5-15.0 cm),the mean mitosis count was(5.44±5.21)/50 high-power field(HPF)(range of mitosis count:0/50 HPF-19/50 HPF),and the median Ki-67 index was 8%+(range of Ki-67 index:0%+-79%+).The positive rate for CD117 and discovered on GIST 1(DOG-1)was 80%and 81.25%respectively in immunohistochemical staining.There were 23 out of the 50 patients tested with next generation sequencing(NGS),and 6 of themwere detected with potentially significant gene mutations.The median follow-up time was 38.5 months(range of follow-up time:2-191 months)for all patients.The 1-,3-and 5-year progression-free survival(PFS)rates were 77.6%,67.9%and 67.9%,and the 1-,3-and 5-year overall survival(OS)rates were 91.9%,78.4%and 78.4%,respectively.Univariate analysis showed that gender,clinical manifestation,distant metastasis,maximum tumor size,mitosis count,tumor rupture and National Institutes of Health(NIH)risk classification had significant influence on prognosis(P<0.05),and multifactorial survival analysis showed that distant metastasis、tumor rupture and mitosis count were independent factors for long-term survival in WT-GIST patients.Conclusion:WT-GIST has certain particularity in epidemiology,clinical diagnosis and treatment,clinicopathological features and other aspects.Distant metastasis,tumor rupture and mitosis count seemed to be independent factors that influence long-term survival in WT-GIST patients,and further studies with larger sample size are needed to evaluate the influence on patients’survival rate for other prognostic factors.