Sex: female
Age: 70 years
History
Repeated attacks of right upper quadrant pain. The patient had undergone surgery for rectal cancer six years ago.
Laboratory data
Unremarkable.
Physical findings
Unrelated.
Case text
During the preoperative work up of the upper abdomen before gallbladder surgery, ultrasound showed a 2 centimeter big lesion in the right liver lobe. It had high echogenicity but somewhat atypical features, requesting further investigation.
Image 1-4
MRI of the upper abdomen, T2-weighted images.
1.0 TESLA NT-10. T2-weighted TSE images, respiratory triggered, TR 2000, TE 100, 10 mm thick slices.
Image 5-8
MRI of the upper abdomen, T1-weighted images.
T1-weighted TSE images, respiratory compensated, TR 550, TE 15. 10 mm thick slices.
Image 9-13
MRI of the upper abdomen, multi-echo.
T2-weighted images with increasing TE. The sequence is formed of eight echoes at the same location, TR 2000, TE 40, 80, 120, 160, 200, 240, 280 and 320. Here, the first, fifth and seventh echoes are left out (images 9-13).
Image 14-17
MRI of the upper abdomen. T1-weighted gradient echo (TFE) images immediately after contrast injection of 15 ml of Gadolinium.
T1-weighted TFE images with TR 15, TE 4, flip angle 15 degrees.
Image 18-22
MRI of the upper abdomen, repeated T1-weighted images.
T1-weighted TFE images as above, before and 1 min, 5 min, 10 min and 15 min after contrast injection.
Image 1-4
1. Where is the abnormality?
Cranially in the right liver lobe.
2. How can the lesion be described?
Slightly lobulated, well circumscribed mass of high signal intensity.
3. What is the differential diagnosis?
Cyst, cavernous hemangioma, metastasis, adenoma, abscess.
Image 5-8
4. What are the characteristic features of the lesion?
Rather well circumscribed, slightly lobulated.
5. What are the signal characteristics?
Intermediate signal intensity, rather homogeneous.
6. Is the tumor solid or cystic?
Not cystic. A cyst should have low signal intensity on a T1-weighted image.
7. What is the most likely diagnosis?
With the patients history of rectal cancer surgery, a metastasis must be taken into consideration. Hemangiomas are very common benign lesions in the population. Adenomas are more rare but still possible, although on the T2-weighted images an adenoma normally have a somewhat lower signal intensity. Abscess is unlikely because of no clinical suspicion of infection.
Image 9-13
8. What can be said about the signal intensity on this series of images?
On echoes with increasing TE, the signal intensity decreases only marginally, compared to the signal intensity of the spinal canal.
9. What conclusion can be drawn on the basis of this sequence alone?
A hemangioma should have almost the same signal intensity throughout the series. In this case there is a slight drop out of signal but not as much as should be the case with a malignant lesion.
10. How confident can you be about the diagnosis?
The features of the signal intensity pattern on a multi-echo is only indicative. When there is no loss of signal intensity, there is very high confidence on the lesion to be a cavernous hemangioma, but this is often only the case with rather small hemangiomas, whereas the medium or large ones can have atypical patterns.
11. What is the next step to be taken?
Contrast injection, using Gadolinium
Image 14-17
12. Describe the enhancement pattern.
Rather intense contrast enhancement immediately after the injection, homogeneous with some less signaling areas within the lesion
13. What conclusion can be drawn on the basis of the contrast enhancement?
This is a rather typical contrast enhancement pattern for a cavernous hemangioma, but given the patient's history of cancer surgery, a metastasis with small areas of necrosis must be ruled out.
14. What is the most likely diagnosis?
Cavernous hemangioma, metastasis being less probable but still possible.
15. What can be done to further increase your confidence?
Late imaging after contrast injection.
Image 18-22
16. Describe the sequential enhancement of contrast material in the lesion.
From the beginning there is an enhancement in most of the lesion, being more intense in the peripheral parts, with a filling in of contrast in the whole lesion. The enhancement is then slowly equaling that of the normal liver parenchyma.
17. What is the most probable diagnosis?
This enhancement pattern is typical for a cavernous hemangioma of the liver.
18. How does the contrast enhancement behave as compared to CT?
The enhancement pattern is identical to that we are used to see on CT, but MRI is more sensitive.
Final diagnosis
Cavernous hemangioma of the liver
Differential diagnosis
Any solid mass that is hepatic in origin.
Discussion
Cavernous hemangiomas are very common hepatic lesions (up to 25% of the population is being reported as having hemangiomas in the liver at autopsy), almost always being found incidentally, while investigating some unrelated symptoms, for example with ultrasound. They very rarely become symptomatic, and then because of bleeding in a very big hemangioma. The problem is to differentiate this purely accidental finding from other lesions in the liver which can require surgery, such as metastasis or adenomas. This is especially true in a patient with a known history of malignant disease.
The ultrasound features are often very typical with high echogenicity, well circumscribed and a diameter most commonly not passing 2 cm. In an otherwise healthy person this should not require further investigations. If this, however, is considered to be necessary, liver scintigraphy with blood pool imaging is a very sensitive and specific modality if the lesion is over 2 cm in size. The large hemangiomas can be very atypical, though, and the very small ones (< 2cm) are not always detected.
CT with contrast injection and dynamic imaging is a good imaging modality to get further support for a lesion being a hemangioma and in many centers it is considered that if two of the mentioned modalities support the diagnosis of hemangioma, no further work up is necessary.
MRI is very sensitive in detecting lesions in the liver. Multi-echo imaging as described is considered to be diagnostic if the signal intensity pattern is typical and then no other investigation is required. Only a benign cyst can have the same signal pattern and these are ruled out on the basic signal features. If, however, the multi-echo does not provide a typical signal pattern, then contrast injection of Gadolinium with dynamic imaging is a very sensitive tool. As is the case with the mentioned imaging modalities, the very big hemangiomas are atypical even in this case.