How do you Diagnose Brain Metastasis?
Diagnosing brain metastasis at an early stage slightly improves the chances of survival.
Computed tomography (CT) and magnetic resonance imaging (MRI) help to diagnose brain metastases. The lesions are recognized as rounded, well-demarcated regions with surrounding swollen areas. Small tumors or tumors in different regions of the brain, lesions in the brainstem and cerebellum, may all be detected clearly with MRI. Biopsy may be required in some cases to confirm the diagnosis of brain metastases.
How can you Treat Brain Metastasis?
The survival rate of brain metastatic cases has improved with therapies that treat different features of brain metastases or target primary tumors.
Treatment strategy is decided based on relevant prognostic factors that include the type of primary tumor, the tumor stage, the location of the tumor, the molecular and genetic markers of the tumor, age, the number of brain metastases, the health of the patient, and tumor activity. For example, if there are numerous or inaccessible lesions or lesions that affect vital functions, such as speech or movement in the brain, it means the affected person has a poor outcome. If you have poor health, irrespective of the tumor stage or type, palliative care is recommended instead of treating the tumor. Conversely, if you have good health, you will undergo aggressive treatment to tackle the tumor. Breast cancer or non-small cell lung cancer respond well to chemotherapeutic or radiation treatments.
Treatment is specific to the symptoms or the condition, as a whole. In symptomatic treatment, seizures are controlled with antiepileptic medications, while swelling (edema) is treated with corticosteroids.
Brain metastasis can be treated with different approaches, such as focused external beam radiotherapy, chemotherapy, surgical resection, whole brain radiotherapy (WBRT), and CyberKnife® or Gamma Knife® stereotactic radiosurgery (SRS), or other personalized therapeutic approaches.
- Surgical resection: This is the first choice of treatment. Once lesions that are surrounded with swelling and cause deficiencies, are diagnosed, the lesions can be resected followed by radiation or biopsy.
- Stereotactic radiosurgery (SRS): This is preferred following surgical resection because it is a method that targets the radiation beam precisely to the tumor or lesion by using CyberKnife® or Gamma Knife® devices. This treatment is suitable for those with a favorable disease outcome or who have fewer lesions. The quality of life, the control of the tumor, and the survival of tumors are positively enhanced with resection.
- Microneurosurgery: Nowadays, microneurosurgery, along with intraoperative MRI-based neuronavigation helps to resect any lesion in the cerebrum.
- Whole Brain Radiotherapy (WBRT): In most cases, WBRT is performed following surgery; however, there is a risk to cognitive capabilities. The whole brain is subjected to radiation. Patients with more than 3 brain lesions or who cannot undergo surgery or have factors signifying poor outcomes, are good candidates for WBRT.
- Chemotherapy: Based on the tumor type and the location, chemotherapy may also be used to treat brain metastases once resection is complete and the surgical wound has healed.
Advances in Treatment
The following advances in treatment have been tested in clinical trials and are gaining notice for their potential to treat brain metastases.
Brachytherapy: Controlled radiation doses to specific targets help to avoid radiosensitive regions. Iodine-125 and cesium-131 are the isotopes used for this treatment.
Confocal microscopy: Also known as confocal laser scanning microscopy (CLSM), this is an advanced type of microscopy that generates microscopic images having high resolution and contrast. This can be used to observe regions surrounding the resected tumor cavity.
Photodynamic detection: Fluorescent compounds, such as 5-ALA (amino-levulinic acid) and fluorescein, help to highlight lesions or tumor margins during resection. Some drawbacks include staining adjacent regions other than tumors or neurotoxicity.
LITT: Magnetic resonance-guided laser interstitial thermal therapy is being seen as an alternative to failed radiation treatment. The technology helps to successfully target inaccessible lesions in the brain.
Immunotherapy: A recent study indicates that melanoma patients suffering from brain metastases show improved survival with combined immunotherapy using the monoclonal antibodies nivolumab and ipilimumab. Further research may validate the use of immunotherapy.
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