Treating Cancer Patients with Dementia

Chemotherapy may improve survival for older colon cancer patients with dementia.

Cancer and dementia are both diseases associated with aging and as a result, it is not uncommon for elderly men and women to have both conditions. And because chemotherapy can be challenging for older cancer patients with dementia, some patients and families choose to forego treatment.

A study recently published in the American Association for Cancer Research (AACR) journal Cancer Epidemiology, Biomarkers & Prevention showed that foregoing chemotherapy was linked to worse survival in older patients with colorectal cancer who also had dementia.

“In general, dementia patients with advanced colon cancer are being undertreated. There are many good reasons why physicians, patients, and families may decide to forego chemotherapy, including toxicity, functional limitations of the patient, or if patients are diagnosed with colon cancer at later stages,” said Yingjia Chen, PhD, a postdoctoral fellow in the Memory and Aging Center in the Department of Neurology at University of California, San Francisco.

“However, our findings suggest that chemotherapy may increase survival and should be considered for advanced colon cancer patients with dementia in a similar fashion as for those without dementia,” Chen added.

Chen and colleagues conducted retrospective analyses of SEER-Medicare data from 3,903 adults over the age of 65 diagnosed with stage 3 colon cancer and dementia. The researchers found that a diagnosis of dementia prior to the diagnosis of colon cancer was associated with increased risk of death by 45 percent. The mean survival time for patients with stage 3 colon cancer and pre-existing dementia was only 57 percent that of their cognitively healthy counterparts.

But when the researchers examined the impact of the receipt of chemotherapy on survival outcome in patients with dementia using special statistical methods, they found that not receiving chemotherapy accounted for 13 percent of the poorer survival outcomes for patients with pre-existing dementia.

The study authors note: “Future studies should assess the effect of adjuvant chemotherapy on cognitive function in patients with pre-existing dementia and determine whether interventions that enhance the provision of standard adjuvant chemotherapy enhance the survival of patients with concomitant stage 3 colon cancer and dementia.”