PEComa临床病理分析与影像诊断

Clinicopathological analysis and imaging diagnosis of PEComa

目的探讨血管周上皮样细胞肿瘤(PEComa)的临床特点及计算机体层成像(CT)、磁共振成像(MRI)表现,提高对PEComa的诊断准确率。方法收集2021年12月30日中山市人民医院收治的经病理证实的1例肾脏恶性PEComa患者的影像及临床资料,结合搜索2000—2021年期间中国知网(CNKI)、万方数据库资料,分析肿瘤的位置、大小、形态、边界、密度、强化特点及其与周围组织的关系,总结其影像表现。结果本例患者肿瘤位于左肾,经腹腔镜病灶根治术切除,术后病灶经病理证实为恶性PEComa,本研究病例在随访期内,未见转移或复发。回顾文献资料,一共239例患者,男54例(22.6%),女185例(77.4%),其中20例明确指出恶性;临床特点主要表现为腰痛、腰胀,其次是体检无意中发现,较少见的就诊原因为肿瘤破裂出血急诊就诊、血尿、腹部包块、其他地方病变检查无意中发现等。病理特点:组成PEComa的上皮样细胞呈放射状排列分布于血管周围,胞浆透明至嗜酸性,常表达黑素细胞和肌源性标记物,黑色素瘤相关抗原(HMB45)+为特征性表现。影像学特点:内脏或腹膜后肿块边界清楚,平扫低至等密度,轻度/明显不均匀强化。结论PEComa是一种少见疾病,根据临床及CT、MRI等影像学检查有助于提高诊断准确性。

Objective To investigate the clinical characteristics and CT and MRI manifestations of perivascular epithelioid cell tumor(PEComa),and to improve the diagnostic accuracy for PEComa.Methods The imaging and clinical data of pathologically confirmed 1 renal malignant PEComa patient admitted to Zhongshan City People's Hospital on December 30,2021 were collected,and the location,size,morphology,boundary,density,and enhancement characteristics of tumor and its relationship with surrounding tissues were analyzed combined with relevant literatures published in CNKI and Wanfang database from 2000 to 2021,and the imaging manifestations were summarized.Results The patient's tumor was located in the left kidney and underwent laparoscopic radical resection of the lesion.The lesion was postoperatively pathologically confirmed as malignant PEComa.No metastasis or recurrence was found during the follow-up.A total of 239 patients were recruited from the literatures,including 54 males(22.6%)and 185 females(77.4%),20 cases of whom were clearly malignancy.The main clinical features were low back pain and lumbago,followed by unintentional discovery in physical examination,and the rarest reasons were emergency diagnosis of tumor rupture and hemorrhage,hematuria,abdominal mass,and unintentional discovery of lesions in other places.Pathologically,PEComas were composed of epithelioid cells from clear to eosinophilic cytoplasm distributed radially around blood vessels,usually expressing melanocytes and myogenic markers,characterized by HMB45+.Imaging features were visceral or retroperitoneal masses with well-defined boundaries,low to isodense density on plain scan,and mild/obvious uneven enhancement on enhanced scan.Conclusion PEcoma is a rare disease,and imaging examination based on clinical,CT,MRI,and other imaging findings helps to improve the diagnostic accuracy.