后肾腺瘤16例临床特征及诊治分析

Clinical features analysis of metanephric adenoma： a series of 16 cases

目的探讨后肾腺瘤临床特征、影像学表现、治疗方法及预后。方法回顾性分析北京大学第一医院泌尿外科2004年1月至2016年3月收治的16例后肾腺瘤患者资料，对患者的临床特征、影像学特点、手术方式及预后进行分析。结果16例后肾腺瘤患者中，男性6例，女性10例，年龄14～83岁，平均年龄33.7岁。2例因发热症状入院，其余14例因体检发现肾脏占位入院。1例血常规结果提示红细胞增多症，1例存在轻度贫血，所有病例血肌酐在正常范围。11例肿瘤位于左肾，5例位于右肾。所有患者行泌尿系统超声检查，15例行CT检查；14例肿瘤为实性，1例为囊实性，CT值为（41±4）HU，增强扫描呈轻中度强化，CT值为（77±9）HU。6例行MRI检查，T1WI及T2WI呈高或低信号，增强扫描可见强化。肿瘤最大径为（4.7±3.9）cm（范围：1.7～17.5 cm）。16例患者均接受外科手术治疗，包括部分肾切除术11例，肾根治术4例，肾输尿管全长切除术1例；其中11例行腹腔镜手术。术后均未出现并发症。16例患者均由术后病理学检查证实为后肾腺瘤，手术切缘均阴性。免疫组化Vimentin、CD57、AE1/AE3、WT1、CK7、AMACR阳性表达例数分别为16、15、12、10、3、2例。16例获得定期随访，随访时间8～125个月，中位随访时间44个月。随访期间无复发或转移，1例于术后125个月因高龄死亡（83岁）。结论后肾腺瘤临床表现及影像学检查难以与肾细胞癌鉴别，病理结果可明确诊断，手术方式首选保留肾单位手术，预后良好，但仍需定期随访。

ObjectiveTo study the clinical characteristics, image findings, therapeutic method and prognosis of metanephric adenoma.MethodThe clinical characteristic, image findings, operation methods and prognosis of 16 metanephric adenoma patients treated at Department of Urology, Peking University First Hospital from January 2004 to March 2016 were analyzed retrospectively.ResultsThere were 6 male and 10 female patients in the study. The mean age of patients was 33.7 years （ranging from 14 to 83 years）. Two patients came to the hospital because of fever, while other 14 patients had no symptoms and found renal tumor by medical examination. One case was found polythemia vera and another 1 case showed mild anemia. Serum creatine of all the cases were in normal range. The tumor of 11 cases were at left side and 5 cases were at right. All patients took urinary tract ultrasound. Fifteen patients took CT examination. Among them, 14 cases were solid mass and 1 case was cystosolid.CT value was （41±4） HU. CT scan showed that the tumor was slight enhanced and CT value increased to （77±9） HU. Six patients took MRI examination. The MRI showed high or low signal of T1WI or T2WI scans.Tumor size was （4.7±3.9）cm （ranging from 1.7 to 17.5 cm）. All 16 patients took operation and 11 of them took laparoscopic surgery while the other 5 cases took open surgery. Eleven cases took partial nephrectomy, 4 cases took nephrectomy and 1 case took nephroureterectomy. The surgical procedures were all successful and no complications occured during perioperative period. All cases were all confirmed metanephric adenoma by postoperative pathology and surgery cut edge were all negative. Immunohistochemical study showed that the positive rate of Vimentin, CD57, AE1/AE3, WT1, CK7 and AMACR respectively were 16/16, 15/16, 12/16, 10/16, 3/16 and 2/16. The median follow-up time of 16 cases was 44 months （ranging from 8 to 125 months） and none had recurrence or metastasis.One case died 125 months after surgery because of advanced age（83 years old）.ConclusionsMetanephric adenoma is difficult to be diagnosed relying on clinical characteristics and image features. Pathology can help confirm the diagnosis. Partial nephrectomy is the first choice for operation and can achieve good prognosis. But it still needs a regular follow-up.