Age Impacts the Efficacy of Immunotherapy in Treating Breast Cancer

Screening for patient-reported quality of life factors may help to identify patients who are at increased risk for early discontinuation of endocrine therapies (ET) for the treatment of breast cancer, according to a study in JAMA Oncology.

“Early discontinuation of adjuvant ET is problematic among breast cancer survivors, with previous studies suggesting that up to 50% of women do not adhere to the recommended full five years of ET treatment,” wrote the study authors.

Risk Factors of Endocrine Therapy Discontinuation

The purpose of this study was to identify modifiable risk factors, polypharmacy, and medication use associated with early discontinuation of ET in patients with breast cancer. The investigators conducted a post hoc analysis of a clinical trial comprising 954 patients with hormone receptor–positive, ERBB2–negative, axillary node–negative breast cancer. The mean patient age was 56.6 years. Patients began treatment with ET within one year of study entry.

All participants were administered assessments of baseline cancer-related health-related quality of life, including physical and social well-being prior to treatment initiation. Early discontinuation was defined as stopping treatment after <4 years for reasons other than death or disease progression.

The investigators found that patients receiving chemoendocrine therapy, compared with ET alone, were less likely to discontinue treatment early (hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.35-0.92; P = 0.02). Compared with patients who were aged younger than 40 years, patients aged >40 years also had reduced risk of early discontinuation (HR for 41–50 years, 0.39; HR for 51–60 years, 0.28; HR for 61–70 years, 0.40; HR for >70 years, 0.23).

A history of depression was found to be a risk factor for treatment discontinuation compared to patients with no depression history (HR, 1.82; 95% CI, 1.19-2.77; P = .005). Poor physical well-being (HR, 2.12; 95% CI, 1.30-3.45; P = 0.002) and social well-being (HR, 1.94; 95% CI, 1.20-3.13; P = 0.006) were both associated with increased incidence of ET discontinuation. Of the assessed medications, antidepressant use at baseline was associated with early discontinuation (HR, 1.87; 95% CI, 1.23-2.84; P = 0.003).

In conclusion, the authors wrote, “In this post hoc analysis of a randomized clinical trial, baseline patient-reported health-related quality of life components, such as poor social well-being, poor physical well-being, and comorbid depression, were significant risk factors for early discontinuation of endocrine therapies. These results support systematic screening for patient-reported outcomes and depressive symptoms to identify women at risk for discontinuation of ET.”

Credit: Original article published here.