Chemotherapy Stops New Healthy Brain Cells From Growing, Worsening Depression In Brain Cancer Patients

According to the findings of a study conducted by researchers from King’s College London, chemotherapy is depressing enough and a drug used in this procedure can possibly heighten it and make it worse.

One of the least recognizable symptoms of cancer is depression, which is commonly attributed to the shock of the patient upon hearing the news. A new study showed that this condition is an actual symptom of the disease instead of just being a psychological distress stemming from receiving a cancer diagnosis.

Depression is prevalent among brain cancer sufferers as demonstrated by the research. Studies estimate that 30% of brain cancer patients are dealing with it. Yet, this symptom is under-diagnosed since only 20% of patients are classified to have clinical depression and less than 10% were reported to experience symptoms of depression.

Chemotherapy is a treatment that brings side effects of its own – most famous of which is hair loss.
Researchers used data from animal studies and they were able to determine that chemotherapy may also affect neurogenesis or the growth of new brain cells. They asked whether the effects of chemotherapy on neurogenesis significantly interrupted the biological brain mechanism and if these changes increased the vulnerability of patients to depression.

For the study, a chemotherapy drug known as temozolomide (TMZ) was given to a healthy mouse. TMZ is used in treating brain cancer for humans. After administering the TMZ to the mouse, researchers found a decline in the production of new neurons in the hippocampus, the part of the brain that is related to emotion and memory. Aside from this, they also discovered a direct relationship between neurogenesis and stress, with neurogenesis declining in direct response to the increased production of stress hormones.

This means to show that aside from having lesser brain cells, patients who undergo chemotherapy also have a greater level of stress when exposed to it.

Moreover, there were also substantial changes in the behavior of the mouse who had undergone the procedure and one of the most noticeable of which is the lack of pleasure seeking or behavioral despair. These mimics the behavior observed in people who experience depression such as resignation and lack of motivation.

The said results may be based on mice and may not accurately represent what is actually happening to patients who have depression, but researchers believe that these findings could help improve patient care.

Martin Egeland, a co-author of the study, explained that,

“Our results suggest that chemotherapy may stunt the growth of new brain cells, which has biological and behavioral consequences that may leave people less able to cope with the stress of having cancer. Understanding the specific effects of chemotherapy on mood could lead to improved treatments and increase the quality of life for those affected by cancer.”

There is no other way to test these findings in human. Studies must be conducted to further know the effect of intervention methods, such as cognitive training, for patients and how it can protect them from depression.

Senior author Sandrine Thuret said that,

“We will have to determine when is the best time to intervene and how much time we have. Treating the cancer is the priority of course. However, if we can improve the quality of life of the patient, it can also be a step forward and may reduce their vulnerability to mental health problems.”

The National Cancer Institute lists depression as a cancer symptom. Though many risk factors are directly involved in developing depression, the agency noted that counseling programs can help in dealing with depression. Other ways to combat it is by stress-reduction exercises and developing relaxation skills.