An 83-years-old male was referred to our hospital by his family doctor for hepatological evaluation due to multifactorial liver cirrhosis.
His medical history was positive for metabolic diseases (in particular insulin resistance and dyslipidemia), prostatic hypertrophy, past hepatitis B virus (HBV) and hepatitis C (HCV) infections, the latter eradicated with antiviral therapy in 2018.
The laboratory investigation showed a normal level of alpha-fetoprotein (AFP, 6.0 ng/mL), a normal hepatic function (albumin level 4.3 gr/dL, total bilirubin level 1.6 mg/dL, prothrombin activity 79%) and hepatic enzymes within normal levels (aspartate aminotransferase 23 U/L, alanine aminotransferase 18 U/L, gamma-glutamyl transferase 19 U/L, alkaline phosphatase 94 U/L).
At ultrasound follow-up, a centimetric hypoechoic nodule was identified in the VI hepatic segment in the context of a liver with signs of cirrhosis and steatosis.
Considering the medical history of the patient, the hepatologist requested a MR study of the liver to better characterize the focal liver lesion.
MRI was performed on 1.5 T system (Signa Excite HDxt; GE Healthcare) with a phased-array multi-channel coil; examination was carried out using spoiled gradient-echo (SPGR) T1-weighted in- and out-phase sequences, T2-weighted images, and diffusion-weighted imaging. A 3D fat-suppressed breath-hold T1-weighted LAVA (Liver Acquisition with Volume Acceleration) sequence was performed before and after intravenous administration of Gd-EOB-DTPA (Primovist®, Bayer HealthCare) in a dose of 0.1 mmol/kg of body weight as a bolus injection at a flow-rate of 2 ml/s, followed by injection of isotonic saline (25 ml). Contrast-enhanced dynamic images were acquired in the arterial dominant phase, in the portal-venous phase, in the transitional phase (at 3 min) and in the hepato-biliary phase (about 20 min after administration).
MR confirmed the presence of an 11-mm-in size nodule in the subcapsular VI hepatic segment, near the inferior vena cava, with signal intensity decay in the in/out-of-phase T1-weighted sequences (Fig. 1), whereas the hepatic nodule was not clearly recognizable on diffusion-weighted imaging. The lesion was strictly adjacent to the right adrenal gland from which it was not possible to recognize a clear cleavage plan. After contrast injection, the nodule appeared hyperintense in the arterial phase, showed a wash-out in the portal-venous and transitional phases and resulted hypointense in the hepatobiliary phase (Fig. 2).
On the basis of a possible radiological diagnosis of HCC and to better define the anatomical details and relationship of the nodule with the right adrenal gland, the patient underwent CT of the abdomen that was performed using a 64-slice CT scanner (LightSpeed VCT; GE Healthcare). Patient received plain and triphasic contrast-enhanced CT (arterial, portal-venous and delayed phase) after intravenous injection of non-ionic iodinated contrast medium (iomeprolo 400 mg/mL, Iomeron 400, Bracco), covering the upper abdomen. On CT scans, the nodule was hyperdense in the arterial phase, appeared hypodense in the delayed phase (Fig. 3) and was vascularized by a thin collateral branch of the right hepatic artery (Fig. 4). Right adrenal gland was partially visualized and very close to the nodule (Fig. 3).
The radiological orientation was that of a neoplastic nature of the nodule, in particular for the diagnosis of hepatocellular carcinoma in a cirrhotic liver. This was supported by the vascular pattern of the nodule both on MRI and CT, by the hypointensity in the hepato-biliary phase and by the clinical context. However, it was not possible to exclude with certainty the possible adrenal relevance also for the signal intensity of the nodule in the in/out-of-phase sequences.
After a long multidisciplinary discussion (hepatologist, radiologist, abdominal surgeon and oncologist), the team decided to propose the surgical treatment to the patient, who accepted. The opportunity of performing a liver biopsy of the nodule was considered, but it was judged technically not feasible by the interventional radiologist.
The patient underwent surgical atypical resection of the caudate process and of a portion of the VI segment near the inferior vena cava, partial resection of the right adrenal gland and cholecystectomy. The patient’s postoperative course was unremarkable.
At macroscopic examination of the surgical specimen, the pathologist observed a yellowish-orange lesion measuring 2 × 1.5 × 1 cm that was located in the subcapsular portion of the liver. Histologically, the mass was composed of large polygonal cells with eosinophilic or pale and lipid-rich cytoplasm, arranged in nest or trabecular pattern with abundant capillary vessels similar to adrenal cortex (Fig. 5). Immunohistochemically, the lesion expressed Melan-A/MART1 and did not stain for liver marker HepPar1 and renal marker PAX8.
The morphology along with the immunohistochemical profile supported the final diagnosis of adrenal rest tumor of the liver.