肝脏血管周上皮样细胞瘤38例临床诊治分析

Analysis of clinical diagnosis and treatment of 38 cases of perivascular epithelioid cell neoplasm of the liver

背景与目的:肝脏血管周上皮样细胞瘤(PEComa)是一种少见的肝脏原发性肿瘤,由于缺乏特异性的症状及影像特征,容易误诊为肝细胞癌、肝血管瘤,影响临床治疗。为探索肝脏PEComa的疾病特点及诊治方法,本研究通过总结我院既往收治的肝脏PEComa患者临床病理资料,对其临床诊疗和预后进行分析,旨在提高对该疾病的诊疗水平。方法:回顾2010年7月—2021年6月期间中南大学湘雅医院普通外科收治的38例肝脏PEComa患者的临床病理资料,对患者的临床特点、影像学表现、病理特点、治疗及预后并进行分析。结果:38例患者中,女性28例(73.7%),男性10例(26.3%),中位年龄46 (21~66)岁。38例患者共发现40个肝脏结节,结节的大小1.0~20.0 cm,平均(6.02±4.84) cm,其中位于右肝21个(52.5%),位于左肝17个(42.5%),位于尾状叶2个(5%)。10例患者有临床症状,表现为腹胀和腹痛或寒战和发热。35例患者行术前肝脏彩超检查,病灶表现为高回声(18例)、混合回声(12例)或低回声(5例)肿块。23例患者术前行增强CT检查,增强后动脉期均出现明显增强,19例在门脉期和延迟期表现为低密度,4例在门脉期和延迟期仍有强化。10例行磁共振检查,其中6例病灶T1加权图像呈低信号,T2加权图像为高信号,3例病灶T1为高信号,T2低信号,1例病灶T1和T2均为等信号;所有病例病灶在弥散加权图像中均表现为高信号。1例行18F-FDG PET/CT检查,肿瘤葡萄糖代谢低,胆碱成像显示病变摄取量异常增高,并在术前误诊为肝细胞癌。所有患者都接受了肝切除手术治疗,包括2例被诊断为肝血管瘤并在外院接受肝动脉栓塞术治疗后发生破裂出血患者。术后病理诊断均为肝脏PEComa,各标志物免疫组化染色阳性率分别为:HMB-45为100%(38/38),CD34为47.4%(18/38),melan-A为44.7%(17/38),SMA为21.1%(8/38)。38例中有34例获得完整随访资料,随访时间3~133个月,中位随访时间为60.5个月,随访期间仅1例于术后3年死亡,余患者均未发现肿瘤复发或转移。结论:肝脏PEComa缺乏特异性的临床表现和影像学特征,术后组织病理学检查是诊断的金标准,当出现症状、良恶性难以鉴别时应尽早手术切除。

Background and Aims: Hepatic perivascular epithelioid cell neoplasm(PEComa) is a rare primary tumor of the liver and is easily misdiagnosed as hepatocellular carcinoma and hepatic hemangioma due to the lack of specific symptoms and imaging features, which affects clinical treatment. To investigate the disease characteristics and treatment of hepatic PEComa, this study analyzed the clinical diagnosis and prognosis by summarizing the clinicopathologic data of previous patients with hepatic PEComa in our hospital to improve the diagnosis and treatment of this disease.Methods: The clinicopathologic data of 38 patients with hepatic PEComa treated in Department of General Surgery, Xiangya Hospital, Central South University between July 2010 and June 2021 were reviewed, and the dataset that included clinical features, imaging manifestations, pathological features, treatment, and prognosis was analyzed.Results: Of the 38 patients, 28 cases were(73.7%) females, and 10 cases(26.3%) were males, with a median age of 46(21-66) years. A total of 40 liver nodules were detected in the 38 patients, and the size of lesions ranged from 1.0 to 20.0 cm, with a mean of(6.02±4.84) cm, among which 21(52.5%) were located in the right liver, 17(42.5%) in the left liver, and 2(5%) in the caudate lobe. Ten patients presented with clinical symptoms such as abdominal distension and pain or chills with fever. Thirty-five patients underwent preoperative liver ultrasonography, and the lesions appeared as hyperechoic(18 cases), mixed echogenic(12 cases), or hypoechoic(5 cases) texture. Twenty-three patients underwent preoperative enhanced CT, and all lesions were enhanced in the arterial phase after enhancement. Nineteen presented hypointense in the portal and delayed phases, and 4 had a prolonged enhancement in the portal and delayed phases. Ten patients underwent magnetic resonance imaging examination, of whom, the lesion showed low signal intensity on T1-weighted images showed and high signal intensity on T2-weighted images in 6 cases, showed high signal intensity on T1 images and low signal intensity on T2 images in 3 cases, and showed equal signal intensity on both T1 and T2 images in one case;the lesions in all cases showed high signal on diffusion-weighted images. One patient underwent 18F-FDG PET/CT scan, on which low glucose metabolism and abnormally increased uptake of 18F-choline of the lesion was observed, and was misdiagnosed as hepatocellular carcinoma before operation. All patients underwent hepatectomy, including 2 cases, diagnosed with hepatic hemangioma and suffered rupture and bleeding after treatment with transcatheter arterial embolization in other hospitals. The lesions in all patients were diagnosed as hepatic PEComa by postoperative pathological examination. The positive rates of immunohistochemical staining for various tumor markers were 100% for HMB-45(38/38), 47.4% for CD34(18/38), 44.7% for melan-A(17/38), and 21.1% for SMA(8/38). Complete follow-up information was obtained in 34 cases of the 38 patients. The median follow-up time was 60.5 months. Only one case died 3 years after surgery, and no tumor recurrence or metastasis was observed in all the other patients during the follow-up period.Conclusion: PEComa of the liver lacks specific clinical manifestations and imaging features, and postoperative histopathological examination is the gold standard for diagnosis. Surgical resection should be performed as early as possible for those with the development of symptoms and lesion challenging to be identified as benign or malignant.