肾混合性上皮间质肿瘤的CT影像特点和外科治疗方法

The CT imaging diagnosis and surgical treatment of mixed epithelial and stromal tumors of the kidney

目的探讨肾混合性上皮间质肿瘤(MESTK)的CT影像特点和外科治疗方法。方法回顾性分析2015年4月至2018年8月经浙江大学医学院附属第一医院手术病理证实的13例MESTK患者的病例资料。男3例,女10例。中位年龄37(22~80)岁。就诊原因分别为腰背部不适伴尿急2例,多囊肾出现血尿2例,体检或其他原因行腹部超声检查发现肾占位性病变9例。2例有多囊肾病史。1例服用避孕药2年,其余患者均否认激素使用史。3例因高血压病服用降压药5~10年,其余患者均否认长期用药史。2例多囊肾患者术前未行尿常规检查,其余患者尿常规检查均正常。术前肌酐中位值67(45~486)μmol/L,肾小球滤过率(GFR)中位值109.28(6.98~132.28)ml/min。术前CT检查示11例为单发病灶,2例多囊肾患者未发现肾肿瘤病灶;囊性肿瘤8例,囊实性肿瘤2例,实性肿瘤3例;肿瘤长径中位值5(2.5~7.5)cm;肿瘤内伴钙化灶4例;增强扫描示囊内分隔和实性成分呈轻至中度斑片状不均匀延迟强化,CT值20~55 HU。R.E.N.A.L.评分中位值7(4~10)分。术前影像诊断良性或低度恶性肿瘤3例,血管平滑肌脂肪瘤1例,多囊肾病2例,囊性肿瘤良恶性待鉴别7例。术前CT分期T_(1a)期8例,T_(1b)期3例。本组13例中,2例因多囊肾伴尿毒症反复血尿行开放式根治性肾切除术,1例因CT提示肾周脂肪粘连,行腹腔镜根治性肾切除术;肾部分切除术10例(开放手术6例,机器人手术3例,腹腔镜手术1例),术中切除肾肿瘤及周围0.5~1.0 cm正常肾组织。结果本组13例手术中,开放手术8例,术中出血量30~100 ml;腹腔镜和机器人手术5例,术中出血量20~100 ml。肾部分切除术的术中热缺血时间中位值20(17~40)min。13例术后病理均诊断为MESTK,手术切缘均为阴性。13例均未出现严重并发症,术后无特殊治疗。术后随访时间中位值21(12~41)个月,13例均未见肿瘤复发和转移征象。结论MESTK的CT影像多表现为囊性或囊实性肿瘤,实性肿瘤少见,分隔或实性成分轻至中度延迟强化具有一定特征性,如病灶内出现粗大钙化,诊断该病的可能性较大。MESTK首选肾部分切除术,术前CT检查提示肾周粘连性脂肪时,需考虑行根治性肾切除术。

Objective To investigate the CT features and surgical treatment of mixed epithelial and stromal tumor of the kidney(MESTK).Methods From April 2015 to August 2018,13 patients with MESTK confirmed by pathology at the First Affiliated Hospital,College of Medicine,Zhejiang University,were enrolled in this study and their clinical data were analyzed retrospectively.These patients included 3 males and 10 females,with age ranging from 22 to 80 years old and the median age of 37 years old.Two patients complained of lumbar discomfort with urinary urgency and another 2 patients presented with hematuria.Nine patients were asymptomatic and their renal lesions were detected by abdominal ultrasonography for physical examination or other reasons.There were 2 cases had a history of polycystic kidney disease,1 patient took contraceptive for 2 years,and 3 cases took antihypertensive agents for 5-10 years.The other patients denied any administration of hormone or other medicine for long time.The urine routine test was normal for these patients except for 2 patients did not take this test before operation.The creatinine value ranged from 45 to 486μmol/L,with the median value of 67μmol/L.The scope of glomerular filtration rate(GFR)was 6.98 to 132.28 ml/min,with the median value of 109.28 ml/min.The preoperative computer tomography(CT)showed single neoplasm in 11 patients and no obvious neoplasm was found in 2 patients who had polycystic kidney disease.Moreover,these lesions presented cystic neoplasm for 8 cases,cystic-solid neoplasm for 2 cases and solid neoplasm for 3 cases.Long diameter was measured about 2.5 to 7.5 cm,with the median of 5 cm,and calcification was found in 4 cases.These tumors manifested mild to moderate enhancement and delayed-enhancement for tumor parenchyma and intracapsular septum.The CT attenuation value was from 20 to 55 Hounsfield unit(HU).Base on the R.E.N.A.L.score system,these renal lesions got 4 to 10 points,with the median value of 7 points.Before operation,just 1 case was diagnosed as angiomyolipoma and 2 cases were diagnosed as polycystic kidney disease.No definitive diagnosis was made for the other 10 cases by CT imaging.In addition,the tumor staging based on preoperative imaging was made at T_(1a) for 8 cases and T_(1b) for 3 cases.Among these cases,2 patients with polycystic kidney disease underwent open radical nephrectomy due to recurrent hematuria and uremia.One patient underwent laparoscopic radical nephrectomy due to perirenal fat adhesion.Partial nephrectomy was performed in remaining 10 patients by open surgery for 6 patients,robotic surgery for 3 patients and laparoscopic surgery for 1 patient.These renal tumors and 0.5-1.0 cm surrounding normal renal parenchyma were removed during operation.Results In this study,8 patients had blood loss of 30 to 100 ml during open operation,and 5 patients had blood loss of 20 to 100 ml during laparoscopic or robotic surgery.The warm ischemic time during partial nephrectomy was around 17 to 40 min,with the median value of 20 min.All of 13 cases were diagnosed as MESTK by postoperative pathology and the surgical margin was negative.There were no serious complications or special treatment after operation.The follow-up time ranged from 12 to 41 months,with the median time of 21 months.Obvious signs of tumor recurrence or metastasis were not detected in 13 cases during follow-up.Conclusions CT images of MESTK mostly presented cystic or cystic-solid lesions,and solid lesions were relatively rare.This disease always showed mild to moderate enhancement and delayed enhancement of septal or tumor parenchyma.If there is coarse calcification in the lesions,it is more likely to be diagnosed as MESTK.Partial nephrectomy is preferred and radical nephrectomy should be considered when perirenal fat adhesion is suggested by the preoperative CT images.