Exploring gene-environment interactions in breast cancer-related lymphedema among African women: a narrative review

Breast cancer-related lymphedema (BCRL) is a chronic and life-altering complication that affects 20-30% of breast cancer survivors globally. While both genetic and environmental factors contribute to its development, current knowledge on gene-environment interactions is largely derived from high-income countries, with minimal applicability to African populations due to differences in genomic profiles and environmental exposures. This narrative review explores the genetic and environmental factors contributing to BCRL among African women, emphasizing the lack of genomic data and region-specific studies. A comprehensive narrative review was conducted using PRISMA guidelines. Searches across PubMed, Embase, and Cochrane (March 2018-December 2024) identified studies assessing genetic markers and environmental risk factors contributing to BCRL. Eligibility included peer-reviewed studies focused on gene-environment interactions in breast cancer survivors, particularly within or relevant to African contexts. Out of 150 retrieved articles, only five studies investigated genetic contributions to BCRL, none of which were conducted in Africa. Studies from the USA and Europe have identified key genetic markers such as FLT4, VEGFA, and APOE, with reported BCRL prevalence ranging from 10% to 30%, often considering additional risk factors like surgery and Body Mass Index (BMI). Asian studies indicate emerging interest, with Single Nucleotide Polymorphisms (SNPs) linked to genetic susceptibility. However, there is a notable lack of data from African populations, where no genetic studies were identified, underscoring a significant gap in global genomic research. Overall, the average BCRL prevalence across studies is approximately 20%, but representation remains limited, particularly in under-researched regions like Africa. There is a critical need for genomic research tailored to African women to identify risk factors and inform precision medicine in BCRL prevention and care. Strengthening local research infrastructure and integrating genetic screening into oncology services are essential next steps.