What is Cavernous Hepatic Hemangioma?
Hepatic hemangiomas are non-cancerous blood-filled growths in the liver. These are the most common type of harmless tumors in the liver. Hemangiomas are lined with a special type of cells known as endothelial cells and surrounded by thin, fibrous tissue; due to their structure, they’re sometimes referred to as cavernous or capillary hepatic hemangiomas. Usually, they don’t cause any symptoms and are often discovered during imaging tests for other reasons. They usually occur as a single growth, but sometimes multiple growths can be found. They are classified based on their size: small ones are 1 to 2 centimeters in size, typical ones are 2 to 10 centimeters, and giant ones are larger than 10 centimeters. These hemangiomas can also appear in other parts of the body like the spinal cord, eye sockets, or spine, but this explanation is focused on those that occur in the liver.
What Causes Cavernous Hepatic Hemangioma?
The exact cause of liver hemangiomas, which are noncancerous liver tumors, isn’t fully known. They can just appear without any known causes. When these hemangiomas are bigger than 10 centimeters, they are referred to as giant hemangiomas.
These hemangiomas are considered as abnormal blood vessels. They grow by becoming dilated, not by multiplying or enlarging healthy cells. During pregnancy, the hemangioma might increase in size due to a rise in hormones like estrogen and progesterone, although not all tumors have shown to have hormone receptors. Interestingly, some tumors have been known to grow even without the presence of hormone therapy.
There can be additional related abnormalities. One such is focal nodular hyperplasia of the liver, which is a benign condition where nodules, or small lumps, develop in the liver. Another is Kasabach-Merritt syndrome, a rare disease characterized by multiple hemangiomas throughout the body, high levels of a certain protein breakdown product in the blood, and a decrease in platelet count (blood cells that help with clotting).
Risk Factors and Frequency for Cavernous Hepatic Hemangioma
Hepatic hemangiomas are growths in the liver that are five times more likely to occur in females than in males. People can experience these growths at any age, but they are most often found in people aged between 30 and 50. Although quite a lot of people might have these hemangiomas, we can’t be sure about the exact numbers, because they mostly don’t cause any symptoms. So, they are usually only discovered when someone has a scan for something else unrelated.
- Hepatic hemangiomas are liver growths that are more common in women.
- They can occur at any age, but most commonly in those 30 to 50.
- The actual number of people with hepatic hemangiomas might be much higher than reported because they typically don’t cause symptoms.
- They are usually found incidentally during abdominal imaging done for other reasons.
Signs and Symptoms of Cavernous Hepatic Hemangioma
Hepatic hemangiomas, which are liver growths, often don’t cause any symptoms. They’re usually found on scans done for other health issues, like during a type of surgery called a laparotomy or after a person passes away during an autopsy. However, larger hemangiomas (more than 4 cm in size) can cause abdominal discomfort and pain. The most common symptoms include:
- Pain in the upper right area of the abdomen
- Generalized abdominal pain
- Feeling of fullness in the abdomen
If the hemangioma bleeds, it can cause the outer layer of the liver to swell and give rise to sudden stomach pain. If the hemangioma grows large, it may cause symptoms related to it pressing on nearby structures, such as feeling full quickly because of pressure on the stomach. Physical exams and lab tests usually don’t show any specific signs. It’s rare to feel a mass or to see changes in liver function tests.
Testing for Cavernous Hepatic Hemangioma
Hepatic hemangiomas, which are benign liver tumors, can be examined and identified using imaging techniques like computerized tomography (CT), magnetic resonance imaging (MRI), or ultrasonography (US). However, it’s important to understand that to confirm the diagnosis, multiple tests may be necessary. Taking a tissue sample, also known as a percutaneous biopsy, is generally not advised because it runs the risk of causing severe bleeding. The diagnosis process can become more complicated if the patient has other health conditions like liver cirrhosis or cancers outside the liver, and may necessitate additional tests or imaging.
In an ultrasound scan, a hepatic hemangioma usually appears as a uniform, clearly outlined mass that reflects sound waves strongly. However, if the patient has liver steatosis, a condition where fat builds up in the liver, the hemangioma may reflect sound waves weakly. Ultrasound scans sometimes show irregularities in size or shape when lesions measure more than 5 cm. Giant hemangiomas can look like uneven masses with a border that reflects sound waves strongly. However, these ultrasound characteristics aren’t definitive for diagnosing hemangiomas, which is why additional imaging tests are often required.
In a CT scan without contrast medium, a liquid substance to enhance images, a hepatic hemangioma can appear as a well-defined mass with the same or lower density than blood vessels and the liver. Contrast-enhanced CT scans show a success rate of 88% in sensitivity, which is the ability to identify true positives, and 84% to 98% in specificity, which is the ability to identify true negatives, when diagnosing a hemangioma. After the introduction of the contrast medium, the typical hemangioma shows uneven, peripheral enhancement in the arterial phase images (the first set of images after contrast administration), with the enhancement spreading towards the center over time. Giant hemangiomas show a similar pattern, but there may be a non-enhancing central scar.
Sometimes, the enhancement pattern may not be typical. Instead of spreading from the periphery to the center, it might enhance centrifugally, from the inside out. In patients with liver cirrhosis, hemangiomas may lose their signature enhancement pattern, and small hemangiomas with fast filling can sometimes look like hepatocellular carcinoma, a type of liver cancer.
With regard to MRI, which has a 90% sensitivity and 91% to 99% specificity for diagnosing hepatic hemangiomas, typical hemangiomas show low intensity on T1-weighted images (where fat appears bright and water appears dark) and high intensity on T2-weighted images (where water appears bright and fat appears dark). They are normally well-defined and uniform. Like CT, post-contrast imaging shows peripheral, uneven, nodular enhancement with delayed center-ward filling of the lesion. Hemangiomas that are smaller can show flash-filling and may appear to be hepatocellular carcinoma in patients with liver cirrhosis.
Another tool used in the diagnosis process is a Technetium-99m pertechnetate-labeled red blood cell scan combined with single-photon emission CT. This test has a sensitivity similar to that of MRI for detecting lesions larger than 1 cm, but it hasn’t been proven to have the same value in confirming the diagnosis of hemangiomas. Hemangiomas usually show reduced blood flow or a localized defect during the early dynamic scan, with a peak increase in tracer uptake (a substance that makes tissues more visible) occurring around 30 to 50 minutes after the tracer is injected. The tracer remains within the lesion in the delayed phase images. However, false negatives can occur due to fibrosis, a thickening and scarring of connective tissue, or thrombosis, a local blood clot.
Treatment Options for Cavernous Hepatic Hemangioma
If you don’t show any symptoms, usually no treatment is needed for small liver lesions that are under 5 centimeters. Doctors might periodically check on it to make sure it doesn’t grow or cause any other problems. A biopsy, which is a sample of tissue taken for testing, is typically avoided due to the risk of bleeding.
However, if you do have symptoms or if the lesion is large enough to exert pressure on other organs (“mass effects”), your doctor might consider surgical intervention after ruling out other causes for your discomfort. Some of the surgical options include partial liver removal, tying off the hepatic artery to cut off the blood supply to the lesion, removing the lesion (enucleation), and in severe cases, a liver transplant. Keep in mind that while surgery will likely help, there’s a chance (about 25%) that some symptoms might persist even after the operation.
There are also non-surgical treatment options:
- Hepatic artery embolization – a procedure to block the blood flow to the lesion. This can both limit acute bleeding and shrink the size of the lesion, potentially making surgical removal easier.
- Radiotherapy – this method, which uses high-energy rays to kill cells, is rarely used and typically reserved for lesions associated with Kasabach-Merritt Syndrome, a rare blood disorder. It helps to decrease the lesion size, but it also increases the risk of developing cancer.
- Interferon alfa-2a – this is a type of medication that might work to block the formation of blood vessels in the lesion, although its success rate is questionable.
What else can Cavernous Hepatic Hemangioma be?
Cholangiocarcinomas, a type of cancer that forms in the bile ducts, show a continued increase in visibility when seen through CT scans and MRI images. But these tend to be more diverse when viewed through these imaging modalities and not as brightly highlighted on T2-weighted images, another type of MRI scan. Cholangiocarcinomas frequently block or intrude into blood vessels and bile ducts.
In cases where cancer has spread outside of the liver, one should also think about the possibility of hypervascular metastases – cancer that has spread and has a lot of blood vessels. These often appear as multiple spots at the time they are detected and generally lose their contrast color on delayed phase images, a type of image taken after a delay following the injection of a contrast agent.
Hepatic angiosarcomas, a rare type of liver cancer, also typically show up as multiple spots at the time of detection, and evidence vascular invasion – they intrude into blood vessels, and are more aggressive. Just like hypervascular metastases, these also tend to lose their contrast color on delayed phase imaging. Some spots may also be found in the spleen.
What to expect with Cavernous Hepatic Hemangioma
Most people with liver hemangiomas, which are noncancerous clumps of blood vessels, don’t experience any symptoms. However, those with larger hemangiomas are more likely to display symptoms. The good news is that the outlook is usually positive, meaning most people with liver hemangiomas have a chance of recovering well.
Possible Complications When Diagnosed with Cavernous Hepatic Hemangioma
Complications related to these tumors are usually rare, however, they can still occur. These could include the tumor bursting on its own or the formation of a pus-filled pocket. Most people showing symptoms, like abdominal pain, are often dealing with other digestive system diseases, particularly IBS, since the lesion itself doesn’t typically cause symptoms. Women who have these liver tumors and become pregnant may face complications since the increased levels of estrogen during pregnancy can make the tumor grow. Other potential complications include pressure on other bodily structures, bleeding, blood clot accumulation, and hardening due to calcium build-up.
Complications may include:
- Spontaneous rupture of the tumor
- Formation of an abscess
- Increased symptoms in people with existing digestive diseases
- Growth of the tumor due to increased estrogen in pregnant women
- Pressure on other body structures
- Bleeding
- Accumulation of blood clots
- Hardening due to calcium build-up
Preventing Cavernous Hepatic Hemangioma
Healthcare professionals often advise patients that certain non-dangerous tumors are quite common. While there’s no surefire way to prevent these, adopting healthy habits can improve our overall health and well-being. This involves eating wholesome meals, giving up smoking, and moderating the intake of alcohol.
It’s important for patients to be aware that medications that act like sex hormones can make these tumors, also known as hemangiomas, grow. For women, this includes birth control pills.
If the doctor decides that surgery is the best course of action to remove the tumor, patients should make sure to follow all the typical care steps after the procedure. This will help with recovery and reduce the chance of further health issues.
