Slow accrual of elderly patients with metastatic breast cancer in the Dutch multicentre OMEGA study

Abstract

Background: In a Dutch multicentre study, elderly (65 + year) metastatic breast cancer patients, eligible for first-line chemotherapy, were randomised between two types of single-agent chemotherapy. As accrual was slow, with 78 randomised patients between April 2007 and September 2011, we explored potential barriers in the accrual process and their consequences for characteristics of included patients.

Methods: We sent surveys on the reasons for non-inclusion to all coordinating investigators. We also examined inclusion in a concurrent, non-elderly breast cancer study of the trialists' group and analysed baseline geriatric characteristics of included patients.

Results: Investigators from fifteen participating centres returned the survey. Most commonly reported barriers to inclusion were: patient's refusal of chemotherapy (n = 8) or of randomisation (n = 9), impaired cognition (n = 3) and insufficient cardiac function (n = 2). Oncologists' preference for combination regimens over single-agent chemotherapy was reported twice. Twenty-eight potentially eligible patients, aged 65-71 years, were included in a concurrent, study investigating combination chemotherapy in fit non-elderly patients with metastatic breast cancer. However, baseline characteristics of the included patients showed that the OMEGA study succeeded in including frail and older patients, with a performance status of 2 in 22% of patients and 54% of patients aged 75 years or older.

Conclusion: Accrual in this study was mainly hampered by patient's refusal or preference for a particular type of treatment, and an overall condition considered as too fit or too frail for inclusion. Future trials in elderly metastatic breast cancer patients should focus on non-restrictive inclusion criteria as well as on education of physicians and elderly patients on the advantages of trial participation.