Department of Radiology, Mayo Clinic Arizona, 5777 E Mayo Blvd, Phoenix, AZ, 85054, USA.
Mayo Clinic Alix School of Medicine Arizona, 13400 E Shea Blvd, Scottsdale, AZ, 85259, USA.
Abdom Radiol (NY). 2022 Aug;47(8):2858-2866. doi: 10.1007/s00261-022-03566-6. Epub 2022 Jun 8.
Acquired cystic kidney disease (ACKD) is commonly seen in patients with end-stage renal disease (ESRD), and patients with ACKD have an increased risk of renal cell carcinoma (RCC). Acquired cystic disease-associated RCC (ACD-RCC) was incorporated into the 2016 World Health Organization Classification. This study aims to describe the imaging features of ACD-RCC, which are not well reported previously.
Retrospective review of patients with ACKD who underwent total nephrectomy for concern of a renal mass between 2016 and 2021 yielded 122 nephrectomies in 107 patients. Pathology reports were searched for type and subtype of mass. In ACD-RCC subtypes, imaging studies were evaluated for modality and contrast enhancement (CE). Imaging findings assessed included cystic/solid nature, unenhanced CT (NECT) attenuation, enhancement characteristics [non-enhancing (< 10 HU difference), equivocal (10-20 HU), enhancing (> 20 HU)], subjective MRI enhancement, T1 and T2 signal intensity, restricted diffusion, ultrasound (US) echogenicity, and subjective CEUS enhancement.
148 masses were identified, 122 (82%) of which were malignant and 26 (18%) benign. The three most common tumors were clear cell RCC (n = 47), papillary RCC (n = 35), and ACD-RCC (n = 21). Of the 21 cases of ACD-RCC, 16 had preoperative imaging: CT (15: 6 NECT only, 2 CECT only, 7 combined NECT and CECT), MRI (4), CEUS (5). Ten of these tumors were solid/mostly solid and 6 mixed cystic/solid. On NECT, the average attenuation was 35 HU (range 13-52). Of those with multiphasic CTs, 1 was non-enhancing, 3 were equivocal, and 3 enhanced. All 3 masses imaged with CE-MRI showed enhancement. All 4 tumors evaluated by MRI demonstrated T2 hypointensity and restricted diffusion. All five masses enhanced on CEUS.
ACD-RCC subtype was the third most common renal neoplasm in ACKD patients. Our findings found that no single imaging feature is pathognomonic for ACD-RCC. However, ACD-RCCs are typically solid masses with most demonstrating equivocal or mild enhancement on CT. T2 hypointensity and restricted diffusion were the most common MRI features.
获得性肾囊性病（ACKD）常见于终末期肾病（ESRD）患者，ACKD 患者患肾细胞癌（RCC）的风险增加。获得性囊性疾病相关的 RCC（ACD-RCC）已被纳入 2016 年世界卫生组织分类。本研究旨在描述 ACD-RCC 的影像学特征，这些特征以前报道较少。
回顾性分析 2016 年至 2021 年间因肾肿块而接受全肾切除术的 ACKD 患者，107 例患者共行 122 例肾切除术。对病理报告进行搜索，以确定肿块的类型和亚型。在 ACD-RCC 亚型中，评估了成像研究的方式和对比增强（CE）。评估的影像学发现包括囊性/实性性质、平扫 CT（NECT）衰减、增强特征[无增强（<10 HU 差异）、不确定（10-20 HU）、增强（>20 HU）]、主观 MRI 增强、T1 和 T2 信号强度、弥散受限、超声（US）回声强度和主观 CEUS 增强。
共发现 148 个肿块，其中 122 个（82%）为恶性，26 个（18%）为良性。最常见的三种肿瘤是透明细胞 RCC（n=47）、乳头状 RCC（n=35）和 ACD-RCC（n=21）。21 例 ACD-RCC 中有 16 例有术前影像学检查：CT（15 例：6 例仅行 NECT，2 例仅行 CECT，7 例行 NECT 和 CECT 联合检查）、MRI（4 例）、CEUS（5 例）。其中 10 个肿瘤为实性/大部分实性，6 个为混合性囊性/实性。NECT 上平均衰减值为 35 HU（范围 13-52）。有多层 CT 检查的患者中，1 例无增强，3 例不确定，3 例增强。所有 3 例接受 CE-MRI 检查的肿块均有增强。所有 4 例接受 MRI 检查的肿瘤均表现为 T2 低信号和弥散受限。CEUS 增强的 5 个肿块。
ACD-RCC 亚型是 ACKD 患者中第三大常见的肾肿瘤。我们的研究结果发现，没有单一的影像学特征是 ACD-RCC 的特征性表现。然而，ACD-RCC 通常是实性肿块，大多数在 CT 上表现为不确定或轻度增强。T2 低信号和弥散受限是最常见的 MRI 特征。
