In rare cases, mesothelioma cancer may metastasize (spread) to the patient’s brain. Mesothelioma often begins in the lungs, abdomen or heart after exposure to asbestos. Mesothelioma is a rare disease, accounting for only 0.19% of new cancer diagnoses from 2013 to 2017.
Mesothelioma metastasis to the brain is unlikely. Brain metastasis occurs in only about 3% of mesothelioma patients. Some studies analyze the prevalence of mesothelioma in the brain. They provide insight into how it occurs and potential treatment options.
Can Mesothelioma Spread to the Brain?
Though rare, mesothelioma may spread to the brain. A 2016 study from researchers at Okayama Rosai Hospital studied 150 malignant pleural mesothelioma (MPM) patients. The researchers found eight patients, or 5.3%, developed brain metastasis.
A study by Australian and British researchers found a lower likelihood of brain metastasis, at 3%. The study confirmed mesothelioma is more likely to metastasize to other areas first. Around 87.7% of MPM patients had metastasis sites somewhere in the body. According to this research, mesothelioma is more likely to spread to the lymph nodes and chest cavity.
How Does Mesothelioma Get to the Brain?
Metastasis to the brain can occur when cancer cells spread:
- Through local tissues
- By using the lymphatic system
- By using the circulatory system
The lymphatic system is a network of lymph nodes that filter waste from the body. Cancerous cells may reach the lymph nodes and collect there. If this happens, metastasis in the lymph nodes can occur.
From the lymphatic system, cancer can cross into the bloodstream and enter the circulatory system. Once mesothelioma cells are in the bloodstream, they can cross the blood-brain barrier. The cells can then spread to the brain and lead to tumor development.
Symptoms of Brain Metastasis
Symptoms reported by mesothelioma patients with brain metastasis include:
- Unexplained muscle weakness
- Vision changes
- Speech problems and changes
- Unexplained nausea and vomiting
- Seizures
- Sudden development of headaches or changes in headache frequency
These symptoms differ from common mesothelioma symptoms. Patients experiencing any of these symptoms should contact their doctor immediately. In some cases, individuals may not experience these symptoms, even with brain metastasis.
Risk Factors for Brain Metastasis in Pleural Mesothelioma Patients
One study identified age and cancer stage as common factors among patients with brain metastasis. This study was done by the Okayama Rosai Hospital.
The study found patients over the age of 65 and in stage four of mesothelioma were most likely to have brain metastasis. These factors show brain metastasis is most likely in patients who have lived with mesothelioma for a while. There are no documented cases of brain metastasis appearing first in mesothelioma patients.
The longer a patient lives with untreated mesothelioma, the more likely they are to have brain metastasis. Treating localized mesothelioma first may prevent metastasis.
How to Treat Brain Tumors in Mesothelioma Patients
Due to the rarity of brain metastasis in mesothelioma patients, few patients have received treatment. Patients with brain metastasis are often in late stages of cancer. As a result, they may prefer to treat the symptoms rather than remove the tumors.
Early diagnosis and treatment before metastasis are the best ways to prevent brain tumors.
However, there are three potential treatment options for mesothelioma brain metastasis. This includes surgery, chemotherapy and dexamethasone.
- Surgical removal with craniotomy: This procedure involves removing part of the skull to expose the brain tumor. Surgeons then operate on the tumor to get rid of it.
- Chemotherapy: Chemotherapy is a common treatment for any stage of cancer. It uses chemicals to prevent cancer cells multiplying and halt their spread through the body.
- Dexamethasone: This steroid is used to treat symptoms related to metastatic brain cancer. Using dexamethasone in conjunction with surgery may provide patients with relief before operating on the tumors.
These treatments may help patients with mesothelioma brain metastasis. However, metastasis to the brain is very rare in this cancer. More research is needed to study treatment effectiveness. If you or a loved one with a mesothelioma diagnosis experiences these symptoms, contact your doctor.