When Alzheimers and Cancer Collide

Doctor checking senior mans back in examination room
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I remember when my father got Alzheimer’s. It began as Mild Cognitive Impairment (MCI) and then progressed until it was undeniably Alzheimer’s.

And I remember when my father later got prostate cancer.

And I remember the long discussions with my mother as to what to do.

For those of us who have seen a loved one disintegrate into the hollow shell of someone we used to cherish, the thought of our loved one suffering “The Long Goodbye” that is Alzheimer’s Disease perhaps dying easily, peacefully, and much soon from cancer can appear to be a blessing.

Given that Alzheimer’s Disease, the most common form of dementia, is a disease of aging, and that cancer is also both common and a disease of aging, scenarios like my father’s are not uncommon. But here’s what’s interesting: studies show that Alzheimer’s patients have a lower risk of cancer and that cancer patients have a lower risk of Alzheimer’s. These analyses do not indicate a causal relationship; that is, there currently is no evidence that having the one disease causes the reduction in the risk of getting the other disease. There is only an association, meaning that having one is associated with a decreased likelihood of getting the other (for unclear reasons).

Still, a lower risk is far from no risk. Thus, many Alzheimer’s patients like my father do develop cancer, which represents an extremely challenging situation for both family members and care providers. Out of my family’s personal experience, combined with my professional experience (caring for Alzheimer’s patients later diagnosed with cancer), I find that there are two important questions to ask when trying to determine how aggressively (or if at all) to treat cancer in a person suffering Alzheimer’s dementia:

How Advanced Is the Alzheimer’s?

Alzheimer’s doesn’t tend to progress steadily and linearly, but ultimately it always progresses. For those with very advanced disease (like my father today) or those advancing rapidly toward such a state, the true quality of life does not exist. Nor does the late-stage Alzheimer’s patient possess the mental capability to understand what’s going on when receiving or dealing with the effects of chemotherapy, radiation treatment, or surgery. Such confusing (and physically uncomfortable) events are, for the advanced Alzheimer’s patient, more than confusing. They are terrifying. For many families, a painless, quiet death would be a blessing for their beloved advanced Alzheimer’s sufferer when compared with the terror their loved one would experience (not to mention the physical discomfort) of prolonged cancer treatment.

What Type, Stage, and Cell Grade Is the Cancer?

Untreated, the overwhelming majority of malignancies will cause the death of the patient often years (or in my father’s case, decades) earlier than will death from Alzheimer’s Disease. And many cancer patients die relatively peaceful deaths, their bodies quietly giving out from widely metastatic (spread) disease. But other cancers are of the type, stage, and/or cell grade (general aggressiveness) associated with a high likelihood of a painful or distressful death if left untreated. Cancer spread to the bones, as was a high risk for my father, is often extremely painful and difficult to treat. Cancer spread to the lungs and inner lining of the chest can cause fluid build-up that greatly impedes breathing. Again, severe bone pain and gasping for oxygen tests the mettle of the sharpest cancer patients; in demented sufferers, the fear is overwhelming.

When our family asked these two questions, the answer for my father was clear. First of all, his Alzheimer’s was not yet so far advanced, and he still has some quality of life. He still knew my mother (and smiled endlessly in her presence) and recognized his sons as people he loved. He still happily listened to the singsong voices rising through his window from the neighboring pre-school yard. But even had his Alzheimer’s been far advanced, as it is now, we would have chosen to treat his prostate cancer. That’s because, unlike most prostate malignancies, my father’s has the characteristics of a very aggressive cell type, carrying with it a high likelihood of spread to the bones, which I knew from my extensive patient care experience would be very painful and difficult to quiet.

In the end, the choice is left to the family (most often the spouse) of the Alzheimer’s patient to act in what they deem is in the best interest of their loved one. For some, cancer must always be treated regardless of the spouse’s dementia. For others, a peaceful exit at the hands of a malignancy is the last gift one spouse can bestow upon their loving life partner. It is difficult to judge if either approach is wrong, but if the non-treatment pathway is one you ever consider for your loved one, ask these two questions.

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