What is Myxopapillary Ependymoma?
The tumor called myxopapillary ependymoma, first identified by Kernohan in 1932, is a unique type of spinal cord tumor that commonly develops in the lower back region. It makes up 13% of all such spinal tumors and accounts for 90% of all tumors in the conus medullaris, the tapering end of the spinal cord. Myxopapillary ependymoma is a benign (not cancerous) and slow-growing tumor that has been graded as a level 2 severity by the World Health Organization.
What Causes Myxopapillary Ependymoma?
Myxopapillary ependymoma is a type of tumor that originates from a part of the spine called the filum terminale, which is composed of nerve tissue. So far, no specific factors have been identified that increase the risk of developing this kind of tumor.
Sometimes, myxopapillary ependymomas can occur outside the spinal canal (extradural), meaning they are found outside the dura, the outermost layer that covers the spinal cord. These types of tumors are believed to develop from either a structure at the base of the spine (the coccygeal medullary vestige) or from the remnants of the filum terminale located outside the dura.
Risk Factors and Frequency for Myxopapillary Ependymoma
Myxopapillary ependymomas are a type of spinal tumor, making up between 1% to 5% of all spinal tumors and about 13% in the American population. These are seen in about 1 person per million every year. Most people diagnosed with this condition are between 30 and 50 years old, with the average age being 35. The tumor is usually found in the lower part of the spine, specifically in areas known as the conus medullaris and cauda equina. In rare cases, it may also be found in brain cavities known as cerebral ventricles and in the brain itself.
Signs and Symptoms of Myxopapillary Ependymoma
Myxopapillary ependymomas are tumors located below the spinal cord, specifically in the region known as the filum terminale. The symptoms of this condition are not distinct and resemble the symptoms of other intradural tumors. The size, location, and extent of the tumor influence the experienced symptoms. This type of tumor grows slowly, often causing symptoms for months or even years before a proper diagnosis is made. The initial symptoms often lack specificity.
- Patients typically report back pain that worsens at night and while resting
There are also other symptoms associated with myxopapillary ependymomas.
- Motor difficulties
- Sensory abnormalities
- Urination problems
- Walking difficulties
- Enlargement of the neural foramina (pathways for nerves)
- Scoliosis or curvature of the spine
- Scalloping, or an uneven shape, of the vertebral body
- Sudden deterioration of symptoms, including leg weakness and disturbances in the sphincter control (which can occur due to hemorrhage)
Testing for Myxopapillary Ependymoma
For diagnosing a type of spinal tumor called myxopapillary ependymoma, the best method is through magnetic resonance imaging, commonly known as MRI. This imaging technology is chosen due to its ability to show differences in the soft tissues of our body. Other imaging methods, like X-rays or CT scans, could also be used. These can help show changes in the shape of the spinal bone caused by a large myxopapillary ependymoma.
The power of MRI comes from its ability to show the exact size of the tumor and its position relative to other structures of the spine. It also lets doctors see other areas of the spine above and below the tumor, and identify any possible spread of the cancer cells in the spinal fluid, called drop metastases.
These details provided by the MRI are crucial in planning any potential surgery.
On an MRI, a myxopapillary ependymoma may not have unique features that confirm its presence. Generally, the tumor appears as a less bright or equally bright area compared to surrounding tissues on T1 scans, and as a bright area on T2 scans. This has something to do with their mucin content – a type of protein produced by cells.
After a contrast agent called gadolinium is injected into the body, the tumor appears varied, or heterogeneous. Features like bleeding inside the tumor and the formation of cysts are common, which can also affect the appearance of the MRI image.
Despite these variations, there are some features that can give doctors a hint towards a diagnosis of myxopapillary ependymoma. Here are those features:
– A mass in the thoracolumbar region (where your thoracic spine meets the lumbar spine) that’s present within the spinal canal but outside the spinal cord and nerves.
– The tumor stretches across multiple vertebrae mainly in the lumbar (lower back) and sacral (bottom of the spine) regions.
– On T1-weighted images, the tumor appears as less bright or equally bright to surrounding tissues.
– On T2-weighted images, it appears as a bright area.
– After injecting a contrast agent, the tumor shows a strong, uniform enhancement.
– Typically, there’s a slightly less intense region at the edge of the tumor on T2 images.
– In about half of the cases, degeneration leading to cyst formation occurs either toward the head (rostral) or the tail (caudal) end of the tumor.
Treatment Options for Myxopapillary Ependymoma
Myxopapillary ependymomas are not too common, which is why there are no specific treatment guidelines. However, experts generally agree that the best course of action is surgical removal. Detecting and treating this condition proactively is crucial for leading to the best possible outcomes.
The most effective remedy typically involves surgically removing the entire tumor. For many patients, this approach leads to a complete recovery. Doctors usually attempt to perform surgery as soon as possible to ensure better results after the procedure.
However, complete removal of the tumor can be risky, particularly if the tumor is located in the conus medullaris (lower end of the spinal cord) or intertwined with the nerve roots of the cauda equina (the bundle of nerve roots at the lower end of the spinal cord). Care needs to be taken during surgery as nerve roots could pass directly through the tumor.
If the entire tumor cannot be removed, further treatment with radiation therapy is usually suggested. In young children who might be more susceptible to the harmful effects of radiation therapy, chemotherapy can be used instead. However, it’s important to remember that the effectiveness of chemotherapy for treating myxopapillary ependymomas is still not established, although some suggest it could be a good way to prevent the disease from coming back.
Overall, complete surgical removal of myxopapillary ependymoma often leads to positive outcomes in both children and adults, similar to other types of spinal cord ependymomas. Long-term survival chances are typically better when the entire tumor is removed compared to only partially removing it.
What else can Myxopapillary Ependymoma be?
When it comes to a differential diagnoses for filum terminale and small conus myxopapillary ependymomas (a type of slow-growing tumor found at the base of the spinal cord), some conditions could be mistakenly diagnosed. These include:
- Fibrous meningioma: It can be confused with the fibrillary variant of the mentioned ependymomas.
- Paraganglioma: However, the ependymomas don’t show chromogranin-A and are GFAP positive.
- Schwannoma: It could also be mistaken with the fibrillary variant of the ependymomas.
Additionally, conditions like carcinoma or meningioma could mimic the appearance of the epithelial and papillary versions of myxopapillary meningioma.
When dealing with a larger version of this ependymoma that causes damage to the sacrum (the bone at the base of the spine), the following conditions could also be mistakenly diagnosed:
- Chordoma
- Aneurysmal bone cyst
- Chondrosarcoma
- Giant cell tumor
- Metastatic carcinoma: However, ependymomas do not show signs of unusual cell changes, have a lower Ki-67 LI, and are focally fibrillar.
What to expect with Myxopapillary Ependymoma
Currently, medical professionals can’t predict the future course of a disease, the chances of it coming back, or spreading just by looking at body tissue samples or an MIB-1 index, a measurement used in lab tests. After a surgery, patients are usually advised to go for regular MRI scans to check for the return of the tumor. This is necessary even if the surgery seemed successful in removing the entire tumor, as the likelihood of it returning ranges between 10% and 19%.
Despite the success rates of surgical removal, the tumor may come back and can sometimes spread. The chances of the tumor coming back or spreading have been associated with the patient having the clinical history of less than 1 year, on how much of the tumor was able to be removed during surgery, atypical tissue, and lesions extending into the spinal cord.
Myxopapillary ependymomas, a type of brain and spinal tumor, is considered a non-cancerous tumor of the central nervous system known for its long-term survival rates and likelihood of coming back. However, in some cases, it can take a more aggressive turn, leading to the spreading of cancer cells to the spinal fluid and even to other parts of the body.
Even though it generally seems to be well-developed and formed, there are times when it behaves in an aggressive manner. Local progression is quite common, and it can also spread to other body parts, with the lungs being the most commonly affected. Spreading throughout the body is more common when the tumor originates somewhere outside the spine. The estimated survival rate over 10 years is approximately 92.4%, with a disease-free survival rate of around 61.2% in the same time span.
Factors such as age (younger than 36 compared to 36 and older), the treatment method used (surgery alone vs. surgery and radiation), and the extent of the surgical removal can impact the control over the tumor and disease-free survival rates. The 5-year overall survival rate for myxopapillary ependymoma patients is really good ranging from 90% to 100%. Patients who go through complete removal of the intradural myxopapillary ependymomas during surgery have a good prognosis with an average survival time of 19 years.
Although this type of tumor is rarely seen in children, when it does occur, it tends to have a more aggressive course with an increased risk of recurrence and spreading compared to adults. The reason behind its more aggressive nature in children is currently unknown.
Possible Complications When Diagnosed with Myxopapillary Ependymoma
Some studies have suggested that removing myxopapillary ependymomas of the filum terminale in one piece may be beneficial. It has been observed that this method, termed “en-bloc removal,” resulted in the disease spreading in only 10% of cases. Conversely, when these tumors were removed in multiple smaller pieces, known as “piecemeal removal,” the disease spread in 19% of reported cases.
During the surgery, a risk factor is the possible rupture of the tumor capsule, which can sometimes cause the spread of the disease via the cerebrospinal fluid. Research suggests that in about 30% of cases, this could lead to disease spreading and treatment failure.
Several factors have been found to increase the risk of relapse and metastasis: if the myxopapillary ependymoma is found within the spinal cord, a patient’s medical history of less than a year, the scale of the surgical removal, and if the tumor appears to be abnormal upon examination.
Important Factors to Consider:
- Method of surgery (en-bloc vs. piecemeal)
- Potential for tumor capsule rupture
- Location of the myxopapillary ependymoma
- Patient’s medical history
- Extent of tumor removal
- Nature of the tumor (typical vs. atypical)
Preventing Myxopapillary Ependymoma
If you are experiencing pain that radiates from your spine and general back pain, it may be a good idea to meet with a neurologist, a doctor who specializes in treating conditions involving the nervous system. It’s crucial that the team of healthcare professionals looking after you make sure you are well-informed about myxopapillary ependymoma, a type of non-cancerous tumor.
You should also be guided towards educational websites to assist you in better understanding this condition, what to expect from it, and how it’s generally treated. Learning about your condition is extremely important for understanding the processes that may lead to a myxopapillary ependymoma and how to prevent it. Often, nurses with special training play a fundamental role in this education and support process.
