Brain metastasis

File:Metastatic adenocarcinoma - cerebellum - very low mag.jpg

Metastatic adenocarcinoma in the cerebellum at very low magnification

MRI of brain metastasis with contrast

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Gross pathology of melanoma metastasis

Brain metastasis refers to the spread of cancer cells from their original site to the brain. It is a common complication of cancer and significantly affects the prognosis and quality of life of cancer patients.

Etiology

Brain metastasis is caused by the spread of cancer cells from a primary tumor to the brain. The most common primary cancers that metastasize to the brain are lung cancer, breast cancer, melanoma, kidney cancer, and colorectal cancer. The cancer cells travel through the bloodstream or lymphatic system to reach the brain.

Pathophysiology

The pathophysiology of brain metastasis involves several steps. First, cancer cells detach from the primary tumor and invade the surrounding tissue. They then enter the bloodstream or lymphatic system and travel to the brain. Once in the brain, the cancer cells extravasate, or move out of the blood vessels, and invade the brain tissue. They then proliferate and form a secondary tumor.

Clinical Presentation

Patients with brain metastasis often present with neurological symptoms such as headache, seizure, vertigo, nausea, vomiting, and neurological deficits. The symptoms depend on the location and size of the metastasis.

Diagnosis

The diagnosis of brain metastasis is usually made by magnetic resonance imaging (MRI) or computed tomography (CT) scan. These imaging studies can show the presence and location of metastases in the brain. A biopsy may be performed to confirm the diagnosis and determine the type of cancer.

Treatment

The treatment of brain metastasis depends on the type and stage of the primary cancer, the number and location of the metastases in the brain, and the patient's overall health. Treatment options include surgery, radiation therapy, chemotherapy, and targeted therapy.

Prognosis

The prognosis of brain metastasis is generally poor, with a median survival time of a few months. However, survival can be extended with appropriate treatment, and some patients may live for several years.