Chemotherapy damages the brain

Memory problems and concentration disorders due to chemotherapy

27.11.2012

Chemotherapy, which is part of a cancer therapy, can produce changes in the brain. This would explain why cancer patients often suffer from memory problems or poor concentration during and after such treatment. US researchers first published their study results at the annual meeting of the Radiological Society of North America (RSNA).

Using positron emission tomography (PET), combined with computed tomography (CT), scientists have been able to demonstrate physiological evidence of the negative effects of chemo on the brain. It turned out that the funds used cause lasting damage to brain metabolism. Brain areas that are responsible for planning and assigning priorities are particularly affected. For this reason, cancer patients often complain during and after chemotherapy of difficulty concentrating and memory impairment.

Mental disorders with organic cause
"Chemotherapy patients also describe the phenomenon as a mental fog and loss of coping strategies," reports Rachel A. Lagos, a diagnostic radiologist at West Virginia University School of Medicine and West Virginia University Hospital in Morgantown. So far, the causes of the side effects were still unclear.

The so-called "chemo-brain" is not a subjective experience, but a consequence of the treatment, emphasizes the researcher and study author. The research has shown that "the functional disorders caused by the chemotherapy are visibly identifiable during the brain scan".

For the study, Lagos and colleagues investigated the functions of the brains of 128 patients who were prescribed chemo because of breast cancer. The brain regions were recorded before and after the therapy. With the help of PET, the scientists were able to measure the blood flow and examine different brain activities of individual areas. A specially programmed software then searched the images for differences in brain metabolism.

Changes in the brain clearly visible
"When we saw the results, we were surprised because the changes were very obvious," Dr. Lagos. The so-called "chemo-brain phenomenon" is therefore more than just a feeling. It is not a patient's depression. It is a change in brain function that is observable on PET / CT imaging. "The images showed a markedly reduced metabolic activity after chemotherapy for several regions in the brain than before. "The study shows that certain areas of the brain consumed less energy after chemotherapy," Dr. Lagos. "These brain regions are responsible for the planning and prioritization." The observed effects were the more pronounced, according to the scientist, the more the subjects suffered from cognitive disorders.

Previous research has shown that patients benefited from the help of dieticians and physical therapists. For example, during the study, participants complained that they found it difficult to prepare a meal for their family. "With shopping slips and written menus, women were once again able to buy groceries," says Dr. Lagos.

Lagos, her colleagues, now hope that they have paved the way for better treatment to reduce the side effects of chemotherapy. "The next step should be a prospective study," said the expert. Further research could identify and narrow down the causes. This could also lead to improved treatment or prevention. (Sb)

Also read:
Chemotherapy can be counterproductive in cancer
Chemotherapy in breast cancer does not always make sense
Breast cancer: Gentest should prevent chemotherapy