Effect of low-level laser therapy on pain and swelling in women with breast cancer-related lymphedema: a systematic review and meta-analysis

This study aims to examine literature on effectiveness of low-level laser therapy (LLLT) in reducing limb volume and pain in adults with breast cancer-related lymphedema (BCRL). PubMed, PEDro, CINAHL, and Cochrane databases were searched using (lymphedema OR edema OR swelling) AND (breast cancer OR mastectomy) AND (laser OR low-level laser therapy OR LLLT OR cold laser). Intervention studies or meta-analyses reporting LLLT for BCRL were included in the search. Pooled effect sizes (ES) and 95 % confidence intervals (CI) were calculated for volume and pain. No limitations were placed on length of follow-up, publication year, or language. Final search was conducted on October 16, 2014. Nine studies met criteria for inclusion. Within-group pooled ES for volume (six studies) was -0.52 (-0.78, -0.25), representing a 75.7-ml reduction in limb volume after LLLT. Between-group pooled ES for volume (four studies) was -0.62 (-0.97, -0.28), representing a 90.9-ml greater reduction in volume with treatment including LLLT versus not including LLLT. Within-group pooled ES for pain reduction (three studies) was -0.62 (-1.06, -0.19), pain reduction of 13.5 mm (0-100 mm VAS). Between-group pooled ES for pain reduction (two studies) was non-significant at -1.21 (-4.51, 2.10). Moderate-strength evidence supports LLLT in the management of BCRL, with clinically relevant within-group reductions in volume and pain immediately after conclusion of LLLT treatments. Greater reductions in volume were found with the use of LLLT than in treatments without it. LLLT confers clinically meaningful reductions in arm volume and pain in women with BCRL.