Hepatic epithelioid hemangioendothelioma
Tokushima University Hospital
Drs. Tomoki Matsushita and Masafumi Harada, Dept. of Diagnostic Radiology
Dr. Masao Yuasa, Division of Clinical Technology
DATE : 2021
Introduction
Patient’s background
Female; 30s; body weight: 47 kg; hepatic epithelioid hemangioendothelioma
Assessment objectives
No subjective symptoms. Multiple hepatic tumors were detected by ultrasonography as part of a regular health check-up, and hepatic epithelioid hemangioendothelioma was diagnosed on the basis of thorough tests, including biopsy, by the previous physician. The patient was referred to the authors’ hospital to look into the option of surgery, and preoperative contrast CT was performed.
Contrast agent used
Iopromide 300 injection syringe 100 mL, “BYL” / 90 mL
Case explanation
A diagnosis of epithelioid hemangioendothelioma was made on the basis of liver biopsy by the physician responsible for referral, and preoperative contrast CT at the authors’ hospital showed characteristic signs of that disease, confirming the diagnosis. Multiple tumors were found, primarily in the marginal region of the liver, and they were low-absorption lesions with relatively clear borders, and heterogeneous, gradually increasing contrast enhancement. Left lobectomy, partial right lobectomy, and microwave coagulation therapy were performed at the authors’ hospital, but recurrence was found approximately 6 months later, and radiofrequency ablation therapy was performed. The patient is currently still being followed up after treatment.
Imaging findings
A tumor found in the liver margin does not show early dark staining
Fig. 1. Arterial phase
Retraction deformation of the liver surface is shown, reflecting tumor fibrosis.
Fig. 2. Portal phase
Heterogeneous, gradually increasing contrast enhancement can be seen.
Fig. 3. Equilibrium phase
There are multiple low-absorption masses with relatively clear borders.
Fig. 4. Simple CT (Note: CT images from other dates are also shown for reference.)
Photography protocol
| Equipment used | CT device model | Aquilion ONE Vision Edition / Canon |
| Number of CT detector rows / number of slices | 320 rows |
| Imaging conditions | Imaging phase | Arterial-dominant phase | Portal-dominant phase | Equilibrium phase |
| Tube voltage (kV) | 120 | 120 | 120 | |
| AEC | On | On | On | |
| AEC settings | SD7.5 | SD7.5 | SD7.5 | |
| Beamwidth (mm) | 40 | 40 | 40 | |
| Slice thickness (mm) | 0.5 | 0.5 | 0.5 | |
| Focal-spot size | Large | Large | Large | |
| Scan mode | Helical | Helical | Helical | |
| Scan speed (s/rotation) | 0.5 | 0.5 | 0.5 | |
| Pitch | 0.813 | 0.813 | 0.813 | |
| Scan range | Upper abdomen | Upper abdomen | Chest to pelvic region | |
| Imaging duration (s) | 5 | 5 | 12 | |
| Imaging direction | Head to foot | Head to foot | Head to foot |
| Reconstruction conditions | Arterial-dominant phase | Portal-dominant phase | Equilibrium phase | |
| Routine: Reconstructed slice thickness / interval (mm/mm) | 1mm/1mm | |||
| Routine: Reconstruction function / iterative approximation method | FC14/AIDR3D standrad | |||
| Contrast conditions | Arterial-dominant phase | Portal-dominant phase | Equilibrium phase | |
| Automatic injector model and manufacturer | Dual Shot GX7 (Nemoto Kyorindo) | |||
| Contrast agent used | Iopromide 300 injection syringe 100 mL, “BYL” | |||
| Contrast agent: Dose | 90mL | |||
| Contrast agent: Injection speed, injection duration | 3mL/sec | |||
| Scan timing | BT (subphrenic / 130 HU) | |||
| Delay time | 15sec | |||
| Indwelling needle size (G) | 22G | |||
| Injection pressure limit (kg/cm2) | 14kg/cm2 | |||
This is a routine protocol for upper abdominal dynamic testing.
Roles of contrast computed tomography (CT) in diagnosis of the disease
Hepatic epithelioid hemangioendothelioma is a non-epithelial tumor derived from the vascular endothelium, and is known to show low to moderate malignancy and slow growth. Imaging shows it to be fundamentally ischemic, and often multiple. In addition, enhancement at the margins, and a delayed-enhanced region are sometimes found. Furthermore, it is characterized by leading to retraction at the liver surface, which reflects fibrosis.
Consistently with the above characteristics, the present patient showed multiple tumors, primarily in the liver margin, and retraction at the liver surface. Absorption was lower with simple CT than in the background liver (CT value: 46 HU), and heterogeneous, gradually increasing contrast enhancement was found in the arterial phase, portal phase, and equilibrium phase by dynamic contrast CT using iopromide (respective CT values: 59, 66 and 82 HU).
In terms of other diseases that lead to retraction at the liver surface, and thus require differentiation, hepatic cirrhosis, cholangiocellular carcinoma, and hepatic metastasis are generally put forward. There are also several relatively rare conditions such as primary sclerosing cholangitis and angioma, in addition to the present patient’s conditions. In particular, as cholangiocellular carcinoma and hepatic metastasis are also ischemic, they are often difficult to differentiate.
Epithelioid hemangioendothelioma must be put forward for differentiation when multiple ischemic masses with signs of capsular retraction are found in the liver margin by contrast CT.
CT techniques and imaging protocol settings
The protocol used is often used for thorough tests of the upper abdominal region at the authors’ hospital. Imaging was performed in the following three phases: arterial-dominant phase, portal-dominant phase, and equilibrium phase. AEC was used. The contrast agent used contained iodine at a dose of 300 mg/mL, as appropriate to the patient’s body type.
- *The case introduced is just one clinical case, so the results are not the same as for all cases.
- *Please refer to the Package Insert for the effects and indications, dosage and administration method, and warnings, contraindications, and other precautions with use.
