Breast cancer can develop from a number of tissues within the breast. Once the breast tumor, called the primary tumor has developed, a few cells can break off from the tumor and form secondary tumors throughout the body, a process called metastasis. Breast cancers commonly metastasize to a few organs around the body, and very commonly metastasize to the brain. Additionally, the effects of breast cancer on the body can have neurological effects on the nervous system. A number of neurological symptoms can occur as a result of breast cancer, which can be fatal.
Headaches
Headaches are among the most common neurological symptoms of breast cancer. This is caused by an increase in pressure within the skull related to the growth of secondary tumors. The secondary tumors increase the size of the brain to increase pressure, and also interrupt the flow of spinal fluid and cause swelling of neighboring tissue as a result of fluid blockages.
According to Massachusetts General Hospital, headaches that result from brain tumors, such as those developed from breast cancer metastasis to the brain prove most severe in the morning, and dissipate slightly throughout the day.
Ataxia
Breast cancer can also cause ataxia, a degenerative condition which leads to cell death in the brain, causing muscle weakness and uncoordinated muscle movement. Specifically, breast cancer metastasis causes ataxia from degeneration of the cerebellum, a part of the brain that helps signal for muscle movement.
In a 2008 study published in the International Seminar of Surgical Oncology, Dr. A Noorani found that patients with breast cancer developed ataxia, even in the absence of metastasis to the brain. Dr. Noorani suggests that the immune response against cancer cells can attack cells within the brain, leading to ataxia, though further research is needed to better understand the link between breast cancer and ataxia.
Seizures
Breast cancer metastasis to the brain can commonly cause seizures. Seizures are convulsions that occur when cells within the brain signal uncontrollably to each other, inhibiting normal brain function. They cause feelings of dizziness, confusion, temporary deafness, panic or temporary memory loss. Seizures can lead to brain cell death, and create damaging scar tissue which inhibits the function of normal brain cells.
According to Harvard University, metastasis to the brain leads to seizure because tumor growth can cause irritation to the brain. Additionally, growth of tumors increases pressure within the skull, which can also cause seizures.
