Health related quality of life of patients with breast cancer in Malaysia: evidence from EQ-5D-5L and EORTC QLQ-C30

PURPOSE: Health-related quality of life (HRQoL) data among patients with breast cancer (BC) in Malaysia remain limited. This study aimed to describe HRQoL and identify its key predictors to inform future health policy planning. METHODS: A cross-sectional survey was conducted between April 2023 and January 2025 among BC outpatients in eight public specialist hospitals in Malaysia. Sociodemographic and clinical data were collected alongside patient-reported outcome measures, including the EuroQol-5 Dimension 5-Level questionnaire (EQ-5D-5L), a preference-based health utility measure, and the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30), a cancer-specific HRQoL questionnaire. Multivariable linear regression models were used to identify independent predictors of HRQoL for each instrument. RESULTS: The mean (standard deviation) EQ-5D-5L health state utility value (HSUV) was 0.853 (0.179), the mean EQ-VAS score was 79.2 (19.1), and the mean (standard deviation) EORTC QLQ-C30 summary score was 83.3 (15.3). The EQ-5D-5L dimensions with the highest prevalence of reported problems were pain/discomfort and anxiety/depression. The EQ-5D-5L HSUV and VAS score demonstrated moderate to strong positive correlations with the EORTC QLQ-C30 summary score (ρ = 0.503 to 0.672, p < 0.001). In multivariable analysis, advanced cancer stage, Chinese ethnicity, and lower education were independently associated with poorer EQ-5D-5L HSUV. EQ-VAS scores were associated with Indian ethnicity and completion of the questionnaire in English. For EORTC QLQ-C30, advanced cancer stages and Chinese ethnicity remained significant predictors. CONCLUSION: HRQoL among patients with BC in Malaysia was primarily influenced by cancer stage, ethnicity, and education level. Advanced cancer stage was consistently associated with poorer patient-reported outcomes. The complementary use of EQ-5D-5L and EORTC QLQ-C30 provides more comprehensive estimates to inform survivorship care and future economic evaluations.