A systematic review of public health interventions to address breast cancer inequalities in low- and middle-income countries

Background
Breast cancer is the most diagnosed cancer in the world, with a worse prognosis documented in low- and middle-income countries. Inequalities pertaining to breast cancer outcomes are observed at within-country level, with demographics and socioeconomic status as major drivers.

Aim
This review aims to aggregate all available evidence from low- and middle-income countries on public health interventions that can be utilized to reduce breast cancer inequalities within the breast cancer continuum.

Methods
The study was a systematic review and narrative synthesis of available literature, with the literature search conducted between September and October 2021. The search was re-run in September 2022 to update the review. PubMed, Scopus, Embase, African Index Medicus and LILACS were searched, based on predetermined criteria. Randomized controlled trials, cohort studies and quasi-experimental studies were included for review, while studies without an intervention and comparator group were excluded. The Joanna Briggs Institute family of checklists was used for quality assessment of the included studies. Data pertaining to study design, quality control and intervention effectiveness was extracted.

Results
A total of 915 studies were identified for screening and 21 studies met the selection criteria. Only one study specifically evaluated the impact of an intervention on breast cancer inequalities. Diverse, multi-level interventions that can be utilized to address breast cancer inequalities through targeted application to disadvantaged subpopulations were identified. Educational interventions were found to be effective in improving screening rates, downstaging through early presentation as well as improving time to diagnosis. Interventions aimed at subsidizing or eliminating screening payments resulted in improved screening rates. Patient navigation was highlighted to be effective in improving outcomes throughout the breast cancer continuum.

Conclusion
Findings from the systematic review underline the importance of early detection in breast cancer management for low- and middle-income countries. This can be achieved through a variety of interventions, including population education, and addressing access barriers to public health services such as screening, particularly among under-served populations. This study provides a comprehensive database of public health interventions relevant to low- and middle-income countries that can be utilized for planning and decision-making purposes. Findings from the review highlight an important research gap in primary studies on interventions aimed at reducing breast cancer inequalities in low- and middle-income countries.

PROSPERO registration number: CRD42021289643