Sugi M, Lombardi A, Krishnan I, Sandrasegaran K
Mayo Clinic Arizona, Department of Radiology, 5777 E. Mayo Blvd, Phoenix, AZ 85054, USA.
Clin Radiol. 2025 Feb;81:106775. doi: 10.1016/j.crad.2024.106775. Epub 2024 Dec 12.
This study aimed to identify the imaging feature of perinephric myxoid pseudotumor of fat (PMPF) in a large cohort.
Institutional radiology and pathology databases were queried for PMPF for the period from January 2010 to December 2023. Of the 22 identified individuals, two were excluded due to nonavailability of computed tomography (CT) or magnetic resonance (MR) images and five due to lack of pathological confirmation. The study cohort comprised of 15 individuals (males = 10), with median age of 59 years (range: 26-87 years). Three abdominal radiologists in consensus reviewed all relevant CT, magnetic resonance imaging (MRI) and positron emission tomography (PET) images.
Seventeen tumuors were analysed since two individuals had bilateral tumuors. The tumuors were at the renal hilum (n=7) or perinephric space (n=10). Two imaging patterns were seen: hazy ill-defined predominantly fatty mass (n=9) or a soft tissue mass (n=8) with variable fat content (0-90%). At presentation, the tumuors ranged in size from 1.5 to 16.5 cm (median: 6.2 cm). The perihilar tumuors encased central renal vessels without occlusion or thrombus. Ureteric encasement and mild hydronephrosis were seen in 11 and 4 tumuors, respectively. Most (9 of 13) of the affected native kidneys and all transplant kidneys (n=5) showed parenchymal poor contrast enhancement. Tumuors with greater than 12-month follow-up (n=11) showed a median growth of 15%.
PMPF may be considered in the diagnosis of tumuors with soft tissue and fat components situated at the renal hilum or perinephric space. The delayed contrast enhancement, relative lack of mass effect for size, and poor function of affected kidney are diagnostic features.
本研究旨在确定一大组肾周脂肪黏液样假瘤（PMPF）的影像学特征。
查询机构放射学和病理学数据库中2010年1月至2023年12月期间的PMPF病例。在22例确诊患者中，2例因无法获取计算机断层扫描（CT）或磁共振（MR）图像被排除，5例因缺乏病理证实被排除。研究队列包括15例患者（男性10例），中位年龄59岁（范围：26 - 87岁）。三位腹部放射科医生共同回顾了所有相关的CT、磁共振成像（MRI）和正电子发射断层扫描（PET）图像。
由于2例患者为双侧肿瘤，因此共分析了17个肿瘤。肿瘤位于肾门（n = 7）或肾周间隙（n = 10）。观察到两种影像学表现：边界模糊不清的以脂肪为主的模糊肿块（n = 9）或脂肪含量可变（0 - 90%）的软组织肿块（n = 8）。初诊时，肿瘤大小为1.5至16.5 cm（中位值：6.2 cm）。肾门周围肿瘤包绕肾中央血管，但无闭塞或血栓形成。分别在11个和4个肿瘤中观察到输尿管包绕和轻度肾积水。大多数（13个中的9个）患侧天然肾和所有移植肾（n = 5）显示实质对比增强不佳。随访超过12个月的肿瘤（n = 11）显示中位生长率为15%。
对于位于肾门或肾周间隙、具有软组织和脂肪成分的肿瘤，诊断时可考虑PMPF。延迟对比增强、相对与大小不成比例的占位效应以及患肾功能不佳是其诊断特征。
