胃肠道血管球瘤15例临床病理学分析

目的探讨胃肠道血管球瘤(GIGT)的组织病理学特征、诊断及鉴别诊断。方法收集郑州大学第一附属医院2011年1月至2018年6月诊断的15例GIGT,分析其临床病理特征、免疫表型、BRAF基因突变及预后,并复习相关文献。结果15例GIGT,男性7例,女性8例。14例发生于胃,1例发生于回肠。患者年龄37~59岁,中位年龄49岁,平均50岁。11例胃血管球瘤以间断腹痛、腹胀入院,另3例于体检时发现胃窦部占位入院;1例回肠血管球瘤以腹痛伴大便带血入院。影像学检查,胃血管球瘤位于黏膜下,边界清楚,动脉期强化明显;肠血管球瘤累及局部肠壁全层并堵塞管腔。大体检查:瘤体最大径1.5~3.0 cm不等,平均2.3 cm,切面实性。显微镜下观察:胃血管球瘤位于固有肌层间,富血管,与周围分界清楚,但均无明显包膜形成;瘤细胞大小一致,呈圆形或卵圆形,围绕血管周围呈血管外皮瘤样或实性巢团状排列;细胞形态温和,核圆形居中,染色质细腻,核仁不明显,核分裂象难见,无坏死,其中2例局部见小灶状钙化;2例见肿瘤侵入黏膜层;2例见脉管瘤栓;5例见神经侵犯。肠血管球瘤累及肠壁全层,细胞密度高,异型性明显,核分裂象热点区约(5~6)个/HPF。免疫组织化学显示,瘤细胞弥漫强表达平滑肌肌动蛋白(SMA)和Ⅳ型胶原,部分区域中等强度表达Caldesmon或Calponin,有12例局部弱表达突触素。胃血管球瘤的Ki-67阳性指数1%~30%不等,均值约6%。肠血管球瘤的Ki-67阳性指数约70%。15例GIGT均未检测到BRAF基因V600E位点突变。所有患者手术治疗后均未行放化疗。电话随访到13例患者,随访时间18~90个月,平均42个月,12例胃血管球瘤患者均健存,肠血管球瘤患者术后15个月出现肝转移。结论血管球瘤是胃肠道少见的间叶源性肿瘤,应与胃肠道间质瘤、神经内分泌肿瘤、平滑肌瘤、孤立性纤维性肿瘤及副节瘤等鉴别。多数GIGT生物学行为良善,预后良好,但尚需长期临床随访。

Gastrointestinal glomus tumors: a clinicopathological analysis of fifteen cases

Objective To investigate the clinicopathological features,diagnosis and differential diagnosis of gastrointestinal glomus tumors(GIGT).Methods Totally 15 cases of GIGT were collected at the First Affiliated Hospital,Zhengzhou University,from January 2011 to June 2018.The clinicopathological features,immunophenotype,BRAF V600E mutation and prognosis were retrospectively analyzed.Results The 15 patients′age ranged from 37 to 59 years(median 49 years,mean 50 years).Eleven patients presented with intermittent abdominal pain and distention,three showed antral space-occupying lesions at physical examination,and one had abdominal pain accompanied by fecal blood.Fourteen tumors were located in the stomach,and one was in the ileum.Imaging showed the gastric glomus tumors were located in the submucosal layer with obvious enhancement in the arterial phase,and the ileum glomus tumor involved the whole layer of intestinal wall causing luminal obstruction.The maximum diameters of the tumors ranged from 1.5 to 3.0 cm(mean 2.3 cm).Grossly,the gastric glomus tumors were solid.Microscopically,the gastric glomus tumors were mostly located in the muscularispropria layer and were vascular.The tumor boundary was distinct but without capsule formation.The tumor cells were round or oval,and showed perivascular hemangiopericytoma-like or solid nest-like structures.The tumor cells were mildly pleomorphic,with rare mitosis and no necrosis.Two tumors had focal calcification,two showed mucosal invasion,two showed vascular invasion and five showed perineural invasion.The ileum glomus tumor was cellular,with prominent cellular atypia,and the mitotic count in hot spots was about 5-6/HPF.Immunohistochemistry showed that SMA and collageⅣwere strongly expressed in all the tumor cells;caldesmon and calponin were moderately expressed in some regions,and syn was weakly expressed in 12 cases.The Ki-67 proliferation index in the gastric glomus tumors ranged from 1%to 30%(mean 6%);and that in the ileum glomus tumor was about 70%.BRAF V600E mutations were not detected in any of 15 GIGTs.All patients did not receive radiotherapy or chemotherapy post operatively.Thirteen patients were followed up by telephone for 18-90 months(mean 42 months).Twelve patients with gastric glomus tumors survived without recurrence and metastasis,and the patient with ileum glomus tumor had liver metastasis 15 months after operation.Conclusions Glomus tumors is a rare mesenchymal tumor of the gastrointestinal tract.It should be differentiated from gastrointestinal stromal tumors,neuroendocrine tumor,leiomyoma,solitary fibrous tumor and paraganglioma.Most GIGTs are benign and have good prognosis.More experience is needed to understand the biologic behavior and prognostication of GIGTs.