What is Liposarcoma?
Liposarcoma is a rare type of tumor that originates from lipoblasts, the cells responsible for fat production. This tumor usually affects deep soft tissues like the esophagus, the tube that connects your throat to your stomach, retroperitoneum, an area in the back of your abdomen, and popliteal fossa, located in the back of your knee.
The place in the body where this tumor might grow depends on its subtype. For instance, one type known as dedifferentiated liposarcoma is often seen in the retroperitoneum while another type, myxoid liposarcoma, commonly grows in the lower parts of the legs.
It’s extremely rare for liposarcoma to occur in the esophagus. If it does, it typically behaves as a slow-growing tumor and usually affects the upper part of the throat. These tumors are usually well-differentiated, meaning they look similar to normal, healthy cells and are confined to the esophagus with a low risk of spreading. However, they do have a high likelihood (10%) of reoccurring locally, which means they can come back in the same area where they were first found, sometimes even up to 25 years after they have been surgically removed.
What Causes Liposarcoma?
We still don’t know what exactly causes Liposarcoma, a type of cancer. The American Cancer Society has found some factors that seem to increase the risk of developing these sort of cancers, but often, patients with Liposarcoma don’t have any of these risk factors. Scientists are still doing research to discover the specific genetic changes that lead to such cancers.
According to the American Cancer Society, factors that might increase the risk of Liposarcoma include exposure to radiation (particularly from radiation therapy used to treat other types of cancer), certain inherited cancer syndromes, damage or injury to the body’s system responsible for fighting infections, and exposure to harmful chemicals.
It’s important to understand that Liposarcomas don’t develop from Lipomas. Lipomas are completely harmless, non-cancerous growths.
Risk Factors and Frequency for Liposarcoma
Liposarcoma is a type of cancer that represents fewer than 20% of all soft tissue sarcomas in the US. It tends to be diagnosed around the age of 50, but occasionally can occur in children. According to the American Cancer Society, it’s the most common type of soft tissue sarcoma worldwide.
There doesn’t seem to be any factors that particularly increase the risk, such as race or gender. However, some studies do suggest it’s slightly more common in males. A very rare type of liposarcoma can form in the esophagus. This is especially uncommon since the most frequently seen cancers affecting the esophagus in the US and worldwide are adenocarcinoma and squamous cell carcinoma, respectively. In fact, sarcomas make up only 0.5% of all tumors found in the esophagus.
There have been fewer than 50 reported cases of esophageal liposarcoma, a really rare condition. These cases are generally seen in middle-aged and elderly males, with a male to female ratio of 4 to 1, and an average age of 62.
Signs and Symptoms of Liposarcoma
Liposarcoma is a type of tumor that appears in different places in the body. Its symptoms and how it shows up depends on its location. It’s commonly found in the limbs, followed by the back of the abdomen, and least commonly, in the esophagus. Most people with liposarcoma don’t have any symptoms. When symptoms do show up, it’s usually because the tumor has grown large enough to affect nearby parts of the body. These symptoms may be pain, swelling, or loss of normal function due to pressure on blood vessels or nerves. Rarely, people might experience numbness or tingling, varicose veins, tiredness, weight loss, nausea, and vomiting. When the liposarcoma is located at the back of the abdomen, it can go unnoticed for a long time because the symptoms aren’t specific and can be missed easily. In such cases, it may become very large before it’s diagnosed.
If a doctor examines a patient with this condition, they might feel a painless lump. If the tumor is at the back of the abdomen, the patient might have a swollen belly. The tumors that are found in the upper part of the esophagus lead to problems with swallowing and weight loss. In extreme cases, when the tumor is large, a lump or mass might even stick out of the mouth. There might also be the regurgitation of food. Rarely, it might result in breathing problems and coughing if the tumor presses on the windpipe.
Testing for Liposarcoma
If your doctor suspects that you might have a liposarcoma, which is a type of cancer, they may use several imaging techniques to examine it. These include a barium swallow, which involves swallowing a fluid that allows your doctors to see your organs more clearly on X-ray images; a computed tomography (CT) scan, which uses X-rays to create detailed pictures of your body; magnetic resonance imaging (MRI), which uses magnets and radio waves to capture images; and esophagogastroduodenoscopy, which is a procedure where a thin, flexible tube with a camera on the end is used to look at your digestive tract.
Although none of these techniques can definitively confirm a liposarcoma diagnosis, a CT scan or an MRI can help your doctor narrowing down what the issue could be. This is because these two tests can detect the amount of fatty component in the tumor. If there’s a lot of fat, it’s usually associated with a benign (non-cancerous) tumor called a lipoma. However, if there’s less fat, it might suggest a more unusual lipoma or a sarcoma. But the only way to be certain is to examine the tissue directly, which means the tumor typically needs to be completely removed.
Different types of liposarcomas can look different on imaging scans. Most liposarcomas have well-defined and often segmented edges. Well-differentiated liposarcomas have a high intensity on T2-weighted images, with minimal change when a dye is injected into your veins to improve the clarity of the images. Myxoid liposarcomas are consistently dense, and may appear outlined on the scan. Pleomorphic liposarcomas have varied internal structures. These last two types show significant differences when a contrast dye is used in the scan.
Before scheduling surgery, your doctor might order an open biopsy. This involves making a small incision and removing a sample of the tumor for testing. The biopsy material will be examined under a microscope to determine the type of cells it contains. This is a critical step for planning your treatment, as it helps the doctor differentiate a liposarcoma from other types of sarcomas. Specialized stains are used to make this distinction.
Treatment Options for Liposarcoma
When treating liposarcoma, a type of cancer that begins in the fat cells, surgery is the most common treatment method. It often involves the full removal of the tumor and some of the healthy tissue around it. For more aggressive or advanced stages of the disease, it may be necessary to couple the surgery with radiation therapy and/or chemotherapy. However, the effectiveness of chemotherapy in treating liposarcoma is not well established, so it’s currently still in an experimental stage.
Radiation therapy, which uses high-energy beams to kill cancer cells, might be a good additional measure to surgery especially if the liposarcoma is of the ‘myxoid’ type (a certain variation of fat cell tumor). For liposarcoma that is located in the esophagus (the tube that connects your throat and stomach), minimally invasive endoscopic surgery or a more extensive partial or total removal of the esophagus may be performed.
There are some examples of radiation therapy being used after surgery to reduce the likelihood of the cancer returning. Nonetheless, there is ongoing debate about whether using chemotherapy and radiation therapy post-surgery really makes a difference, and further research is needed. Owing to the fact that liposarcomas often come back, it is recommended that patients have regular check-ups after their treatment.
What else can Liposarcoma be?
There are a few conditions that might look like liposarcoma (a rare type of cancer that begins in fat cells) when a doctor examines the esophagus both visually and under the microscope. These include:
- Lipoma: This is basically a benign fat tissue formation. It doesn’t contain any lipoblasts (immature fat cells) or irregular nuclei (the center of a cell).
- Fibroepithelial polyp: This often appears as fibrovascular cores with a covering of non-keratinizing squamous epithelium. While larger polyps may look very similar to myxoid or well-differentiated liposarcoma because of their fat and myxoid areas, they can be differentiated by immunohistochemical stains. A polyp of this kind tests negative for both CDK4 and MDM2.
- Leiomyoma/leiomyosarcoma: These are formations of smooth muscle cells that cross each other, and their nuclei have characteristic blunt ends. They test positive for actin and desmin through immunohistochemistry.
- Gastrointestinal stromal tumor: The cells of this tumor are also elongated, but they show immunoreactivity to CD34 and c-Kit (CD117).
These findings underscore the importance of careful analysis to accurately diagnose conditions that may look similar.
What to expect with Liposarcoma
The outlook for people with liposarcoma, a type of cancer in fat cells, can depend on many factors. These include the specific type of the tumor, how aggressive it is, where it’s located in the body, and whether the whole tumor could be removed during surgery.
When liposarcoma is well-differentiated, meaning the cancer cells still look somewhat like healthy cells, it has a 50% chance of coming back after treatment. However, it doesn’t typically spread to other parts of the body and the five-year survival rate is quite good, ranging from 75% to 100%.
On the other hand, myxoid and pleomorphic liposarcomas, which are different variations of this disease, tend to recur more often (up to an 80% chance) and have variable survival rates that can range from as short as 4 months to as long as 107 months.
If the liposarcoma is not properly differentiated, or doesn’t resemble normal cells at all, it can spread to other parts of the body more easily. If any part of the tumor is left behind after surgery, this is also linked to a higher chance of the cancer returning and a poorer survival outlook.
While there are some examples of using additional radiation therapy after surgery to reduce the chances of the cancer coming back, there isn’t a clear agreement among doctors about the role of additional chemotherapy and radiation therapy after surgery for liposarcoma.
Possible Complications When Diagnosed with Liposarcoma
If a liposarcoma in the esophagus is present for a long time, it can result in serious problems. Symptoms might include difficulty swallowing which can lead to anemia and weight loss, a tendency to spit up food which can then be inhaled, the patient may feel choked, and respiratory failure could occur. Having liposarcoma in the limbs or in the back of the abdomen can cause other difficulties. These may be related to localized pressure effects in the abdominal cavity, the structures at the back of the abdomen, and the nerve and blood vessel bundles in the arms and legs.
Complications from long-standing liposarcoma might include:
- Difficulty swallowing
- Anemia and weight loss
- Choking or feeling strangled
- Respiratory failure (unable to breathe)
- Problems due to pressure in the abdominal cavity
- Issues with structures at the back of the abdomen
- Disturbances in the nerve and blood vessel bundles in the limbs
Preventing Liposarcoma
Liposarcoma, a type of cancer that arises in fat cells, can occur in anyone, whether or not there are risk factors or a genetic tendency. As of now, there are no known ways to prevent this disease, which means there’s no method to reduce the number of people it affects.