Quality of Life in Breast Cancer Survivors: A Meta‐Analysis of Case‐Control Studies

BACKGROUND: As the most prevalent malignancy among women, breast cancer has a potentially shattering impact on quality of life (QoL). However, studies comparing QoL between breast cancer survivors and cancer-free peers have been inconsistent and little is known about possible moderators that contribute to inconsistent findings or specific QoL domains that affect breast cancer survivors most. OBJECTIVES: This meta-analysis examined QoL differences between breast cancer survivors and controls without breast cancer ("controls" hereafter) across multiple QoL instruments and domains. METHODS: We searched major international and Chinese databases and identified 36 eligible case-control studies comprising 29,433 participants (12,261 survivors, 17,172 controls). Standardized mean differences were calculated using a random-effects model; subgroup analyses and meta-regression examined potential moderators. RESULTS: QoL impairments varied by assessment instrument. Medical Outcomes Study Short Form surveys showed lower physical component scores in breast cancer survivors (moderate effect size, SMD = -0.52) and small deficits in physical function, emotional role limitations, mental components, and general health domains. The European Organization for Research and Treatment of Cancer questionnaire revealed lower scores in insomnia (SMD = 0.80) and financial difficulties (SMD = 0.77). Regarding the Functional Assessment of Cancer Therapy-General, breast cancer survivors displayed comparatively large impairments across emotional, functional, and physical well-being domains. Short-term survivors (≤ 5 years post-diagnosis) experienced significantly greater deficits than long-term survivors did in physical role limitations and mental health domains. CONCLUSIONS: Breast cancer survivors experience lower QoL than controls do, particularly in physical and emotional domains. This meta-analysis highlights the importance of developing effective interventions targeting specific QoL domains at different survivorship stages.