Brain metastases occur in about 5% of patients with kidney cancer, and about half of brain metastases from renal cell carcinoma are solitary and often combined with severe edema in the vicinity of the metastatic tumor.
How is it detected early?
How to detect early?
The most common symptoms of brain metastases from renal cell carcinoma are headache, malaise, cognitive impairment, seizures, and ataxia; about 7% have no clinical symptoms; those with multiple metastases may present with cognitive impairment, emotional instability, blurred vision, and optic papilledema. Therefore, patients with a history of renal cell carcinoma should seek prompt medical attention once these manifestations occur.
For patients with suspected brain metastases, it is best to have an enhanced cranial MRI (magnetic resonance imaging). CT (computed tomography) may miss smaller lesions, especially those in the brainstem and cerebellum located in the posterior cranial fossa.
How is it treated?
Surgery and radiation therapy are the primary local treatments for patients with brain metastases from kidney cancer, in combination with systemic treatments such as targeted therapy and immunotherapy.
Surgery
Because half of those with renal cell carcinoma brain metastases are solitary metastases with severe peri-lesion edema, the only way to subside the peri-tumor edema associated with the tumor is to remove the lesion, so surgical resection is the treatment of choice for renal cancer brain metastases. Surgical treatment is particularly indicated for the following conditions:
- A single large metastasis (>3 cm), especially if it causes symptoms of increased intracranial pressure such as headache and dizziness;
- Metastases causing associated symptoms, such as epilepsy, limb hemiparesis, aphasia, and sensory disturbances;
- Metastases located in the posterior cranial fossa;
- Patients who are in good health and can tolerate surgical treatment.
Whole brain radiotherapy
Surgery combined with whole-brain radiotherapy reduced tumor recurrence at the resected site, and corticosteroids combined with whole-brain radiotherapy also helped relieve patients’ symptoms, but their symptom improvement did not correlate with imaging tumor shrinkage.
Stereotactic radiosurgery (e.g., Gamma Knife)
It can be used alone or in combination with whole-brain radiotherapy, and the combination has better immediate and long-term outcomes than whole-brain radiotherapy alone. Stereotactic radiosurgery combined with whole-brain external radiotherapy, and surgical resection combined with whole-brain external radiotherapy are both effective treatment strategies, and patients treated with both regimens have similar survival; however, larger (>3 cm) or lesions with significant occupancy effects (midline shift >1 cm) are more amenable to surgical treatment.