Sheikhy Ali, Zahergivar Aryan, Golagha Mahshid, Li Xiaobai, Gopal Nikhil, Homayounieh Fatemeh, Ball Mark W, Turkbey Evrim, Linehan W Marston, A Malayeri Ashkan
National Institutes of Health, Bethesda, USA.
Internal Medicine Department, George Washington University Hospital, Washington D.C., USA.
Abdom Radiol (NY). 2025 Sep 15. doi: 10.1007/s00261-025-05154-w.
Hereditary Leiomyomatosis and Renal Cell Cancer (HLRCC) is a hereditary cancer syndrome associated with germline pathogenic variants of the fumarate hydratase (FH) are at risk for the development of benign renal cysts as well as an aggressive form of renal cell carcinoma which can occur inside the cysts. This study was conducted in order to assess the role of MR imaging characteristics of HLRCC-associated cystic lesions for distinguishing benign from malignant complex renal cysts in this patient population.
This IRB-approved retrospective study included 42 HLRCC patients (mean age, 46 ± 14 years; men: women, 22:20) with a pathogenic FH germline variant with renal cysts on abdominal MRI. Between June 2002 and May 2022 these patients underwent partial or radical nephrectomy for surgical removal of 76 renal lesions suspicious for renal carcinomas. Two abdominal radiologists independently reviewed the MRI images of all lesions while blinded to the surgical pathology. The lesion characteristics, including location, 3D dimensions, internal composition, characteristics of the cyst wall, nodules, septations, enhancement patterns in different series and restricted diffusion on ADC, and b-2000 series were recorded.
Out of the 76 histologically characterized renal lesions, 44 (58%) were found to be benign and 32 (42%) were malignant. Malignant cystic lesions had a significantly larger mean diameter (4.0 ± 3.4 cm) compared to benign lesions (1.8 ± 2.1 cm, p = 0.002). Inter-reader agreement analysis identified 12 imaging features with moderate agreement (κ >0.4). Univariate analysis identified 8 significant predictors of malignancy: "combined areas of enhancement on T1-weighted images during the nephrogenic phase (the nephrogenic phase, occurring approximately 70 seconds after intravenous contrast injection)", "endophytic/exophytic mass", "presence of a nodule", and "nodule enhancement on T1 nephrogenic phase." The final multivariable model for Reader 1 achieved an AUC of 0.86 and for reader 2 with an AUC of 0.91, indicating high diagnostic accuracy. At a predicted-probability threshold of 0.17 (point = 60), the nomogram identified all malignant lesions and would have spared 57% of patients with benign cysts from unnecessary surgery.
Qualitative MRI features, including nodule presence, enhancement patterns, and lesion size, effectively differentiate between benign and malignant renal complex cysts in patients with HLRCC. The final multivariable model achieved high diagnostic, highlighting the potential of MRI in guiding clinical decision-making and improving management of cystic renal lesions in this high-risk population.
遗传性平滑肌瘤病和肾细胞癌（HLRCC）是一种遗传性癌症综合征，与延胡索酸水合酶（FH）的种系致病性变异相关，有发生良性肾囊肿以及囊肿内侵袭性肾细胞癌的风险。本研究旨在评估HLRCC相关囊性病变的磁共振成像特征在区分该患者群体中良性与恶性复杂性肾囊肿方面的作用。
这项经机构审查委员会批准的回顾性研究纳入了42例HLRCC患者（平均年龄46±14岁；男∶女为22∶20），其具有致病性FH种系变异且腹部MRI显示有肾囊肿。在2002年6月至2022年5月期间，这些患者接受了部分或根治性肾切除术，以手术切除76个怀疑为肾癌的肾脏病变。两名腹部放射科医生在对手术病理结果不知情的情况下，独立审查了所有病变的MRI图像。记录病变特征，包括位置、三维尺寸、内部成分、囊肿壁特征、结节、分隔、不同序列的强化模式以及ADC图上的扩散受限情况和b-2000序列。
在76个经组织学特征化的肾脏病变中，44个（58%）为良性，32个（42%）为恶性。恶性囊性病变的平均直径（4.0±3.4 cm）明显大于良性病变（1.8±2.1 cm，p = 0.002）。阅片者间一致性分析确定了12个具有中度一致性（κ>0.4）的影像特征。单因素分析确定了8个恶性的显著预测因素：“肾源性期T1加权图像上的强化联合面积（肾源性期，在静脉注射造影剂后约70秒出现）”、“内生性/外生性肿块”、“结节的存在”以及“T1肾源性期结节强化”。阅片者1的最终多变量模型的AUC为0.86，阅片者2的为0.91，表明诊断准确性高。在预测概率阈值为0.17（分数=60）时，列线图识别出了所有恶性病变，可使57%的良性囊肿患者避免不必要的手术。
定性MRI特征，包括结节的存在、强化模式和病变大小，可有效区分HLRCC患者的良性和恶性复杂性肾囊肿。最终的多变量模型具有较高的诊断价值，突出了MRI在指导临床决策和改善该高危人群囊性肾病变管理方面 的潜力。
