Karmazyn B, Tawadros A, Delaney L R, Marine M B, Cain M P, Rink R C, Jennings S G, Kaefer M
Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Riley Hospital for Children, 705 Riley Hospital Drive, Room 1053, Indianapolis, IN 46202, USA.
Department of Radiology, Memorial Hospital of South Bend, 615 N. Michigan Street, South Bend, IN 46601, USA.
J Pediatr Urol. 2015 Jun;11(3):149.e1-6. doi: 10.1016/j.jpurol.2015.03.001. Epub 2015 Mar 31.
Solitary renal cysts are typically incidentally found in children who have undergone renal ultrasound (US). The main concern is a cystic tumor. There is no US-based grading system for children to guide management.
To evaluate a US-based, modified Bosniak grading system in order to differentiate between simple (grade I or II) and complex (grade II or IV) renal cysts and guide management in children.
This was a retrospective (2003-2011) study of 212 children (114 females), age range one day to 17 years (mean 8.4 years), with solitary renal cysts diagnosed by US. Two radiologists, who were independent and blinded to clinical information, graded the cysts using the modified Bosniak classification system. In children with more than one year of follow-up US, the change (>10%) in cyst diameter was evaluated. Inter-observer variability (Kappa) was calculated.
Radiologists one and two saw simple renal cysts in 96.2-96.6% (204-205/212) of the children. Ten children had complex renal cysts, as rated by either of the radiologists. There was good inter-observer agreement (kappa = 0.65) for simple versus complex cysts. In 20.2% (18/89) of the children, the cysts increased in size. A definitive diagnosis was obtained in 8.5% (18/212) of the children. A cystic tumor (multilocular cystic nephroma) was found in one child (Figure) with a complex cyst (graded III by both radiologists).
The use of a modified Bosniak classification system to grade renal cysts was found to have good inter-observer variability (kappa = 0.65) in differentiating between simple and complex renal cysts. Using this classification, few (<4%) renal cysts were classified as complex. Cystic tumors are rare and the only cystic tumor (multilocular cystic nephroma) was classified as complex renal cysts by the two radiologists. Growth of simple, solitary renal cyst is common (20.2%) and, therefore, if not associated with other imaging findings, is not an indication for a cystic tumor. There were limitations inherent in the retrospective nature of the study and because only one child had a cystic tumor.
The modified Bosniak classification system demonstrated good inter-observer agreement, and identified the single tumor as a complex cyst. The vast majority of solitary renal cysts in children are simple and if asymptomatic, they require no other imaging evaluation. Complex renal cysts are uncommon and should be evaluated with a pre-intravenous and postintravenous contrast CT scan to exclude a tumor.
孤立性肾囊肿通常在接受肾脏超声（US）检查的儿童中偶然发现。主要担忧的是囊性肿瘤。目前尚无基于超声的儿童分级系统来指导治疗。
评估一种基于超声的改良博斯尼亚克分级系统，以区分单纯性（I级或II级）和复杂性（II级或IV级）肾囊肿，并指导儿童的治疗。
这是一项回顾性研究（2003 - 2011年），研究对象为212名儿童（114名女性），年龄范围从1天至17岁（平均8.4岁），这些儿童通过超声诊断为孤立性肾囊肿。两名独立且对临床信息不知情的放射科医生使用改良博斯尼亚克分类系统对囊肿进行分级。对于随访超声超过一年的儿童，评估囊肿直径的变化（>10%）。计算观察者间的一致性（kappa）。
放射科医生1和医生2在96.2 - 96.6%（204 - 205/212）的儿童中发现了单纯性肾囊肿。10名儿童有复杂性肾囊肿，由任何一位放射科医生评级。对于单纯性囊肿与复杂性囊肿，观察者间具有良好的一致性（kappa = 0.65）。在20.2%（18/89）的儿童中，囊肿大小增加。8.5%（18/212）的儿童获得了明确诊断。在一名儿童中发现了囊性肿瘤（多房性囊性肾瘤）（图），其囊肿为复杂性囊肿（两位放射科医生均评为III级）。
发现使用改良博斯尼亚克分类系统对肾囊肿进行分级在区分单纯性和复杂性肾囊肿方面具有良好的观察者间一致性（kappa = 0.65）。使用该分类，很少（<4%）的肾囊肿被分类为复杂性。囊性肿瘤罕见，唯一的囊性肿瘤（多房性囊性肾瘤）被两位放射科医生分类为复杂性肾囊肿。单纯性孤立性肾囊肿的生长很常见（20.2%），因此，如果不伴有其他影像学表现，不是囊性肿瘤的指征。该研究的回顾性本质以及因为只有一名儿童患有囊性肿瘤存在固有的局限性。
改良博斯尼亚克分类系统显示出良好的观察者间一致性，并将单一肿瘤识别为复杂性囊肿。儿童中绝大多数孤立性肾囊肿是单纯性的，如果无症状，无需其他影像学评估。复杂性肾囊肿不常见，应通过静脉注射造影剂前后CT扫描进行评估以排除肿瘤。
