Is the Schonberg Index Effective in Evaluating Mortality Risk Among Older Women With Breast Cancer?

By: Chris Schimpf, BS
Posted: Friday, September 15, 2023

Citing ASCO recommendations to use 10-year mortality probabilities to inform breast cancer treatment decisions, Rebecca A. Nelson, PhD, of City of Hope National Medical Center in Duarte, California, and colleagues conducted a study to assess the utility of the Schonberg index, which predicts risk-based, all-cause, 10-year mortality. Their findings, published in JNCCN–Journal of the National Comprehensive Cancer Network, suggested that Schonberg index–based, risk-stratified mortality rates were similar among women 65 years and older with and without breast cancer. Thus, the investigators concluded that the Schonberg index seems to be a reasonable tool for evaluating older postmenopausal women with nonmetastatic breast cancer when used as recommended in ASCO geriatric oncology guidelines.

“Because the Schonberg index…is guideline-recommended and increasingly used by clinicians, policymakers, and researchers, it is essential to understand its performance and to validate its recommended use in geriatric oncology,” the researchers noted. “Our results…indicate that, taken together with other health analyses, prognostic indexes can be used to predict all-cause mortality in older women with a recent diagnosis of early-stage breast cancer.”

The investigators used Schonberg index risk scoring to calculate 10-year mortality risk scores for 2,549 individuals with breast cancer and 2,549 age-matched individuals without cancer, drawn from the Women’s Health Initiative. They then grouped risk scores into quintiles for comparisons and compared risk-stratified observed mortality rates and 95% confidence intervals across both groups. They also used the Schonberg index to compare predicted 10-year mortality rates with observed 10-year mortality rates.

The researchers reported similar risk-stratified 10-year mortality rates in both groups: 34% among those with breast cancer versus 33% among those without cancer. Stratified results showed slightly higher mortality rates among participants with cancer than those without cancer in the lowest-risk quintile and lower mortality rates in the two highest-risk quintiles. Observed mortality rates in both groups were similar to Schonberg index–predicted mortality.

Disclosure: For full disclosures of the study authors, visit jnccn.org.

JNCCN–Journal of the National Comprehensive Cancer Network

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