Based on the deaths between 2011-2015, the cancer death toll stands at 163.5 per 100,000 men and women in a year. In 2017, there were an approximate 23,880 adults in the US that were diagnosed with cancerous brain and spinal cord tumors. In fact, tumors of the brain add up to 85%-90% of all the CNS tumors. Moreover, brain tumors along with other cancer of the nervous system are positioned as the tenth chief death cause for females.

At the same time, the Alzheimer’s Society of Canada reports that dementia cases are on a sharp rise. As of 2016, roughly 564,000 Canadians had dementia with an estimated 25,000 new cases every year. This number is expected to swell by 66% to 937,000 dementia cases in the country.

While wondering about what causes dementia, it is common for a person to worry about any association between cancer and dementia. Both ailments show a staggering number of victims within their fold. Often, it is also observed that patients with cancer suffer from symptoms of dementia too. Or, they face memory loss in the post-cancer treatment phases. This brings us to the close correspondence between dementia and brain tumors.

This article explores the possible link between late-life cancer and the psychiatric condition of dementia.

What does research say?

Since both dementia and cancer are diseases that typically affect elderly individuals, it is thought they might overlap. Studies see a possible correlation between dementia and cancer. This raises the hopes that one can be alleviated by treating another. Recent research indicates that both the health concerns lie on the opposite ends of the spectrum. This makes their relationship complicated as cancer relates to abnormal cell growth. On the other hand, dementia is concerned with cell death.

Consequently, the association between dementia and cancer is prevalent when the cancer type is narrowed down to align with a particular neurodegenerative disorder. Generally, research claims that dementia and cancer are inversely proportional. In that, a person who develops cancer is less likely to develop a brain disorder or vice versa.

However, other factors also play a role in this association. For instance, age determines that people with cancer do not live long enough to have dementia. The risk of developing symptoms of dementia, however, does not abate in the case of brain tumors. This is because cancer cells in the brain can result in cognitive impairment.

The effect of a brain tumor on memory

Not every person who has a brain tumor suffers from memory loss. On top of it, the severity of the memory loss also varies from one individual to another. The effect of a brain tumor on one’s memory is determined by two main factors viz; the location of the tumor, and the treatment availed.

Numerous brain areas are responsible for recalling and storing memories. Mainly, two key areas specifically serve as memory drawers. These are the temporal lobe and the frontal lobe. The tumor is likely to impact the memory if it happens to be located in these regions.

At the same time, treatment can also culminate in memory loss. Swelling in the aftermath of brain surgery can lead to a myriad of cognitive changes. This happens because radiation, chemotherapy, and surgery can destroy healthy cells that are in the vicinity of cancer cells. This can result in a direct or indirect impact on the brain.

Dementia and brain tumor

Depending on the brain cell damage done during therapy, symptoms include a cognitive decline in speech, thinking, memory, and more. A leading researcher in the field, Dr. Daniel Silverman, confirms this. He highlights, “Published evidence from neuroimaging studies indicates that the post-chemo condition can be associated with decreased metabolism and altered activity in the frontal cortex, particularly in areas of the brain that are important for the recall of language and visuospatial skills.”

If these symptoms emerge immediately, then they result in what is known as delirium. This is characterized by memory loss, confusion, agitation, hallucinations, reduced attention, and the like. On the flip side, if the cognitive changes appear gradually, they result in dementia. These symptoms may be lasting.

The main signs of dementia revolve around poor memory, poor judgment, disorientation, and difficulty in problem-solving. It is here that brain tumors cause dementia. This neurodegenerative disorder can develop early such as within three months of radiotherapy. It can also surface after a long time, say 48 months or more after the therapy is over.

Is dementia due to brain cancer reversible?

Cognitive impairment due to a tumor(s) in the brain can be acute or chronic leading to the development of delirium or dementia, respectively. The former often occurs due to medications that were taken during cancer treatment. Consequently, the symptoms subside as the intake of medication stops.

Chronic cognitive changes that show later on are, however, mostly not reversible. Some medications may be able to help encourage a boost in cognitive functioning. Other symptoms of dementia can also be handled with adequate intervention if they cannot be treated. This is similar to the typical cases of dementia, of which majority are not curable. In fact, only 20% of the dementia causes are considered treatable.

A study also claims that dementia patients have substantially lowered rates of survival. These findings were in contrast with patients who did not have dementia with cancer. Moreover, Medscape indicates that the survival rates vary as per the patient’s age at the time of diagnosis and the dementia type. Typically, such cases pose challenges for healthcare providers too.

Key takeaway

Small but substantial research underlines that dementia and cancer are inversely related. However, treatment and the location of the brain tumor can result in the development of dementia.

If the symptoms of cognitive decline come to the fore during or immediately after the treatment, then the condition is termed delirium. But, if the cognitive impairment is gradual, then it is dementia, and unlike, delirium, it is usually not reversible.

ABOUT Alycia Gordan

Alycia Gordan is a freelance writer who loves to read and write articles on healthcare technology, fitness and lifestyle. She is a tech junkie and divides her time between travel and writing. You can find her on Twitter: @meetalycia