Risk factors of breast cancer-related lymphoedema: protocol of an umbrella review

Introduction Breast cancer-related lymphoedema (BCRL) is a progressive and debilitating complication post-breast cancer treatment. Identifying potential risk factors facilitates the prevention and management of BCRL. Multiple systematic reviews have been conducted to address the variables correlated with the occurrence of BCRL. This study aims to identify and examine factors predicting the development of BCRL, to clarify the predicting mechanism of these factors, as well to determine the credibility of risk factors for BCRL. Methods and analysis This umbrella review will be conducted with the methodological guidance of the Joanna Briggs Institute and the Cochrane handbook. A comprehensive systematic search will be performed in ten databases: PubMed, Embase, CINAHL, Web of Science, Scopus, CNKI, SinoMed, Wangfang database, the JBI Database of Systematic Reviews, Cochrane Database of Systematic Reviews. The search for unpublished studies will include ProQuest and the PROSPERO register. Reference lists will also be hand searched. Two reviewers will independently screen the studies, extract data and assess the methodological quality using the Methodological Quality of Systematic Reviews-2 and the Risk of Bias in Systematic Reviews. The degree of overlap between included reviews will be assessed by calculating the Corrected Covered Area. The credibility of the associations between risk factors and lymphoedema will be graded into four classes: convincing, highly suggestive, suggestive and weak, referring to the classification system of recent umbrella reviews. A descriptive, narrative synthesis and suggestions for clinical practice and future research will be made based on included systematic reviews, considering the quality of the evidence. Ethics and dissemination Ethical approval is not required for this umbrella review. We will seek to submit the results for publication in a peer-reviewed journal or present it at conferences.