Supplementary Material for: MRI USING GADOXETIC ACID IN THE WORK-UP OF LIVER NODULES NOT CONCLUSIVELY BENIGN IN BUDD-CHIARI SYNDROME. A PROSPECTIVE LONG-TERM FOLLOW-UP

Introduction
The incidence of hepatocellular carcinoma (HCC) in Budd-Chiari syndrome (BCS) is unknown and there is no validated diagnostic work-up to define the liver nodules with arterial phase hyperenhancement (APHE) suggesting malignancy. This prospective study evaluates HCC incidence in a Western cohort of patients with BCS and assesses the performance of MRI with hepatobiliary contrast (HB-MRI) for nodule characterization.

Methods
Patients with BCS followed in our hospital were prospectively evaluated by MRI with extracellular contrast (EC-MRI). Nodules with APHE categorized as non-conclusively benign by 2 radiologists, were studied by HB-MRI and reviewed by 2 radiologists blinded to the EC-MRI results. A new EC-MRI one year later and clinical, analytical and sonographic follow-up every six months for a median of 10 years were performed.

Results
A total of 55 non-conclusively benign nodules with APHE were detected at EC-MRI in 41 patients. While 32 of them were suggestive of HCC by EC-MRI, all the 55 nodules showed increased uptake of hepatobiliary contrast. An unequivocal central scar was seen in 12/55 nodules at HB-MRI regardless of it was not detected on the EC-MRI.
None of the nodules was hypointense in the hepatobiliary phase. HCC was not detected during a median of 10 years of follow-up.

Conclusions
Detection of nodules with APHE is frequent in patients with BCS, but HCC is rare in Western patients with BCS. While EC-MRI may detect nodules suggesting malignancy, the identification of contrast uptake in the hepatobiliary phase at HB-MRI may help to categorize them as benign.

Introduction
布-加综合征（Budd-Chiari syndrome, BCS）患者并发肝细胞癌（hepatocellular carcinoma, HCC）的发病率目前尚不明确，且尚无经过验证的诊断流程可用于界定表现为提示恶性的动脉期高强化（arterial phase hyperenhancement, APHE）的肝结节。本前瞻性研究针对西方人群的布-加综合征患者队列，评估其肝细胞癌发病率，并评估肝胆对比剂磁共振成像（hepatobiliary contrast MRI, HB-MRI）在肝结节定性诊断中的效能。

Methods
本研究对本院随访的布-加综合征患者行细胞外对比剂磁共振成像（extracellular contrast MRI, EC-MRI）前瞻性评估。由2名放射科医师判定为非确定性良性的动脉期高强化肝结节，将接受肝胆对比剂磁共振成像检查，并由另外2名对细胞外对比剂磁共振成像结果不知情的放射科医师进行阅片。此外，所有受试者在1年后接受复查细胞外对比剂磁共振成像，并接受为期中位10年的每6个月一次的临床、实验室及超声随访。

Results
本研究共在41例患者的细胞外对比剂磁共振成像中检出55个非确定性良性的动脉期高强化肝结节。其中32个结节经细胞外对比剂磁共振成像提示为肝细胞癌，但所有55个结节均表现为肝胆对比剂摄取增加。在肝胆对比剂磁共振成像中，12/55个结节可见明确的中央瘢痕，尽管该征象在细胞外对比剂磁共振成像中未被检出。所有结节在肝胆期均未见低信号。在为期中位10年的随访期间，未检出肝细胞癌病例。

Conclusions
布-加综合征患者中表现为动脉期高强化的肝结节检出率较高，但西方布-加综合征患者并发肝细胞癌的情况较为少见。尽管细胞外对比剂磁共振成像可检出提示恶性的肝结节，但通过肝胆对比剂磁共振成像识别肝胆期对比剂摄取情况，有助于将这些结节定性为良性病变。