How Age, Comorbidities, and Race Influence Cancer Treatment in Older Patients

Key Takeaways:

• Receipt of treatment varies based on race/ethnicity: Variability of treatment was 76.44% for White patients, 75.18% for Hispanic patients, and 68.47% for Black patients. Black and Hispanic patients were less likely to receive treatment than White patients.
• Treatment rate decreases as comorbidity increases: In a population of 692 159 patients with cancer, 62.7% had comorbidities. Patients with multimorbidity were less likely to receive treatment than patients without multimorbidity.
• Findings illustrate the complex nature of geriatric oncology care: Treatment decreased as age and number of comorbidities increased because therapies have been found to cause increased harm with little benefit in older populations. More research is needed to determine proper forms of treatment for older patients with cancer.

A retrospective cohort study used the US Surveillance, Epidemiology, and End Results (SEER)-Medicare linkage database to survey rates of treatment among older patients with cancer. The researchers aimed to find possible connections between race/ethnicity and multimorbidity and cancer treatment.

Patient Characteristics and Comorbidities

The survey identified 692 159 patients over the age of 66 with 1 of the 4 most common cancer types: female breast, lung, colorectal, and prostrate. Out of this group, 86% of the patients were White, 9% were Black, and 5% were Hispanic.

Nearly two-thirds (62.7%) of patients had 2 or more comorbidities, and 18.27% had 4 or more. The most common comorbidities identified were chronic pulmonary disease, diabetes, and peripheral vascular disease. Patients with lung or colorectal cancer were more likely to have multimorbidity than patients with female breast or prostate cancer.

Receipt of Cancer Treatment

The survey showed that treatment among patients decreased as age, comorbidity, and advanced cancer stage increased. Among all cancer types, older age groups had a lower treatment percentage than younger age groups.

Receipt of treatment also varied based on race: variability was 76.44% for White patients, 75.18% for Hispanic patients, and 68.47% for Black patients. In patients without multimorbidity, Black and Hispanic patients were less likely to receive treatment than White patients.

Patients with multimorbidity, regardless of cancer type, were less likely to receive treatment than patients without multimorbidity. Reception of care for patients with multimorbidity did not appear to be influenced by race/ethnicity, cancer stage, socioeconomic status, or gender.

Explanation of Findings

The authors provide several explanations as to why cancer treatment decreases among older patients and those with multimorbidity. Firstly, common therapies are less beneficial and contain more risk for older patients. Secondly, few clinical trials have assessed older populations, creating a gap in defined care processes. Thirdly, comorbidity has been shown to decrease treatment efficacy and increase toxicity, which could negatively impact quality of life. Finally, multiple treatment combinations could lead to adverse events (AE) in patients.

Moving forward, the authors recommend more research on older patients with cancer and suggest establishing a specialized geriatric oncology consultation as a way to assess patients and prescribe appropriate treatment. They said, “The potential harms and underlying reasons for the racial disparities are not clear at the moment; however, we believe that specialized geriatric oncology consultation that considers complete health status as measured by comorbidity burden could improve outcomes.”

Reference

Pham TT, Connor AE, Rositch AF. Multimorbidity and cancer treatment among the older patients in the United States. PLOS One. 2026;21(1):e0338721. doi:10.1371/journal.pone.0338721