Resistance exercise and breast cancer related lymphedema - a systematic review update

Background: Purpose of this systematic review update was analyzing resistance exercise (RE) intervention trials in breast cancer survivors (BCS) regarding their effect on breast cancer-related lymphedema (BCRL) status. Articles published until 31 September 2017 were included. Methods: A systematic literature search was conducted utilizing PubMed, MEDLINE, and EMBASE databases. Included articles were analyzed regarding their level of evidence and their methodological quality using the Cochrane risk of bias tool. Results: Altogether, 23 articles could be included of which 16 were independent RE intervention studies and seven additional articles. Lymphedema assessment was so heterogeneous that conduction of a thorough meta-analysis regarding lymphedema status was still impossible. In all but one study, which reported a small but methodologically weak increase in arm volume, no negative effects of RE on BCRL was recorded. Conclusions: RE seems to be a safe exercise intervention for BCS and not to be harmful concerning the risk of lymphedema. Lymphedema assessment methods that allow for a qualitative analysis of arm tissue composition should be favored.