Metastatic Brain Tumors: What Are They, What Are the Symptoms, and How Are They Diagnosed?
Metastatic brain tumors develop when cancer originating in another part of the body spreads to the brain tissue over time. Unlike primary brain tumors, which begin in the brain itself, these are classified as “secondary” tumors. In adults, the majority of brain tumors fall into this category.
Receiving this diagnosis is never easy. For patients and their families, it often comes as a shock. Knowing that you are not alone, and being able to reach the right specialists, makes the process more manageable—both medically and emotionally. Fortunately, many effective treatment options are now available in this field.
Are you looking for treatment options? Click the link below.
Treatment Options for Metastatic Brain Tumors.
Why Do Metastases Occur?
Metastasis is the process by which cancer cells break away from the original (primary) tumor and spread to other parts of the body, often through the bloodstream. The brain, due to its rich blood supply, is among the organs at risk. The likelihood of brain metastases depends on the type, stage, and biological characteristics of the cancer.
Cancers That Most Commonly Spread to the Brain
- Lung cancer
- Breast cancer
- Melanoma (aggressive skin cancer)
- Kidney (renal cell) cancer
- Colon and rectal cancer
That said, almost any solid tumor can metastasize to the brain. In some cases, the brain metastasis is the first sign of an undiagnosed primary cancer elsewhere in the body.
What Are the Symptoms?
Symptoms of metastatic brain tumors depend on the location and size of the lesions. The most common symptoms include:
- New or progressively worsening headache
- Nausea and vomiting
- Balance and gait disturbances
- Numbness or weakness on one side of the body
- Speech difficulties or word-finding problems
- Vision loss or double vision
- Personality changes or memory problems
- First-time seizures
In some patients, these symptoms may arise before a cancer diagnosis is made. That’s why rapidly progressing neurological complaints should be evaluated without delay. For example, a patient experiencing new headaches or balance issues might undergo brain imaging—and a metastatic lesion could be discovered. Often, this happens before the primary tumor has been identified.
Diagnostic Process in Metastatic Brain Tumors
When brain metastasis is suspected, imaging studies are usually the first step. These help determine the number, location, and size of the lesions.
Brain MRI (Magnetic Resonance Imaging)
- The most sensitive method for detecting metastatic lesions
- MRI with contrast clearly reveals the spread within the brain
CT Scan
- Provides rapid information in emergency settings
- May be used as an alternative to MRI, especially in patients who cannot undergo MRI
PET-CT
- Used to search for the primary tumor when it is still unknown
- Detects systemic metastases and involvement of other organs
Is a Biopsy Necessary?
- If the primary tumor is unknown and imaging is inconclusive, a brain biopsy may be considered
- This is usually done in special cases before surgery
Laboratory Tests
- May include tumor markers, routine blood tests, and hormonal evaluations
Multidisciplinary Evaluation
Diagnosis is not typically made by a single specialist. Instead, it is usually evaluated by a team including neurology, neurosurgery, medical oncology, and radiation oncology. This collaborative approach allows for more balanced and effective treatment decisions.
If you would also like to learn about how metastatic brain tumors are treated, including surgical and non-surgical options, you can read our follow-up article:
Treatment Options for Metastatic Brain Tumors.
