An inflammatory myofibroblastic tumor in the transplanted liver displaying quick wash-in and wash-out on contrast-enhanced ultrasound

Abstract

Rationale:Inflammatory myofibroblastic tumor (IMT) is an uncommon mesenchymal neoplasm, and its presence in a grafted liver is exceedingly rare.Patient concerns:A 54-year-old woman was admitted to our hospital with a half-month history of intermittent melena. She had undergone deceased-donor liver transplantation (LT) for hepatitis B virus related liver cirrhosis without hepatocellular carcinoma 5 months previously.Diagnosis:Laboratory examination showed impaired liver and renal functions and Epstein–Barr virus (EBV) infection, but tumor markers within normal ranges. Gastroscopy showed esophageal varices. Ultrasound and computed tomography angiography revealed an ill-defined and irregular solitary lesion in the porta hepatis, encasing both the portal vein and the hepatic artery. The lesion was characterized by arterial hyper-enhancement and hypo-enhancement in the remaining phases with contrast-enhanced ultrasound (CEUS). The lesion was finally confirmed as an IMT by ultrasound-guided biopsy.Intervention:The patient received conservative treatment, including immunosuppression, endoscopic variceal ligation, antibiotics, steroids, and antiviral agents.Outcome:The patient's gastrointestinal bleeding was controlled, but the symptoms associated with portal hypertension worsened. Attempts to perform a transjugular intrahepatic portosystemic shunt were unsuccessful, and she unfortunately died soon after.Lessons:A differential diagnosis of IMT should be considered in LT recipients presenting with EBV infection, normal tumor markers, and a de novo hepatic lesion with quick wash-in and wash-out on CEUS. Ultrasound is associated with the advantages of convenience and nonionizing radiation, and should thus be the priority approach for monitoring transplanted liver.

Contrast-enhanced ultrasound approach to the diagnosis of focal liver lesions: the importance of washout

“…Infrequent exceptions to this algorithm have been reported for both benign and malignant masses on CEUS; in particular, some well-differentiated HCCs do not show washout [8], likely due to the similar blood volume of the lesion relative to the liver. Some benign liver masses, including hepatic adenomas, focal nodular hyperplasias (FNHs), and inflammatory pseudotumors may show washout [3,25,26]. It should also be noted that in patients with advanced cirrhosis, the presence and degree of washout of a focal liver lesion may be affected by poor enhancement of the background parenchyma due to decreased portal venous perfusion [27] and decreased vascular volume in the cirrhotic liver.…”

“…In the arterial phase, real-time assessment may demonstrate the characteristic spoke-wheel pattern of APHE with an inside-to-outside, or centrifugal, filling pattern [4] in typical cases of FNH. Studies have shown that some hepatocellular adenomas [25] and inflammatory pseudotumors [3,26] demonstrate washout. Adenomas often show APHE and demonstrate either sustained enhancement or mild washout in the late phase [25,53].…”