A Systematic Review of Health-Related Quality of Life in Women with HER2-Positive Metastatic Breast Cancer Treated with Trastuzumab.

Background: Many trials of human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer treatment with trastuzumab have provided evidence of improved clinical outcomes. This systematic review examined how a regimen that includes trastuzumab affects patients' health-related quality of life (HRQoL) during and after treatment.

Methods: A systematic search for articles published up to February 2023 without restrictions of language or publication year was performed using the Pubmed, Embase, and Scopus databases. We included studies of women aged > 18 years with metastatic HER2-positive breast cancer treated with a trastuzumab-containing regimen. We assessed the quality of the studies using the Cochrane Risk of Bias (RoB) tool (2.0) for randomized controlled trials (RCTs) and the Risk Of Bias In Non-randomised Studies-of Interventions (ROBINS-I) tool for cross-sectional studies. We used Microsoft Excel to extract and synthesize data, and documented the review procedure following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

Results: In total, eight studies compared 1104 trastuzumab-treated patients and 1003 non-trastuzumab-treated patients. Most studies were RCTs (n = 7) and one was a prospective observational study. All the included studies used the EORTC-QLQ-C30, EORTC-QLQ-BR23, FACT-B, or FACT-G questionnaires. During treatment, patients taking regimens that included trastuzumab showed clinical improvement in HRQoL, social functioning, and role functioning. After the treatment, patients' HRQoL profiles in the trastuzumab and chemotherapy arms were similar. However, trastuzumab (versus chemotherapy) treatment led to clinically improved functional status, role and physical functioning, and fatigue. The quality assessment revealed some concerns in most RCTs, with the risk of bias being high in two studies, low in one study, and moderate in the cross-sectional study.

Conclusions: Trastuzumab-containing regimens administered to HER2-positive breast cancer patients at the metastatic stage evidenced beneficial effects on total HRQoL during and after treatment. Upon therapy cessation, patients' HRQoL scores for both interventions improved. Nevertheless, HRQoL profiles of patients treated with trastuzumab were more favorable, particularly for functional status, role functioning, physical well-being, and fatigue.

Clinical trials registration: This review was registered in PROSPERO (registration number: CRD42021259826).