Smoot, B., Chiavola-Larson, L., Lee, J., Manibusan, H., & Allen, D.D. (2015). Effect of low-level laser therapy on pain and swelling in women with breast cancer-related lymphedema: A systematic review and meta-analysis. Journal of Cancer Survivorship: Research and Practice, 9, 287–304. 

DOI Link

Purpose

STUDY PURPOSE: To evaluate the literature on the effectiveness of low-level laser therapy (LLLT) on pain and swelling secondary to breast cancer–related lymphedema (BCRL)

TYPE OF STUDY: Systematic review and meta-analysis

Search Strategy

DATABASES USED: PubMed, PEDro, CINAHL, and Cochrane databases
 
YEARS INCLUDED: No limitations on year of publication; however, October 16, 2014, was the date of the final search. 
 
INCLUSION CRITERIA: Inclusion criteria for studies required that they were an intervention study or meta-analysis to examine the use of LLLT alone or in conjunction with other treatment(s) for BCRL that reported on upper extremity pain and/or swelling. Studies that were identified in existing meta-analyses and that met inclusion criteria were treated as individual studies. 
 
EXCLUSION CRITERIA: Patients with primary lymphedema or secondary lymphedema not related to breast cancer treatment were excluded. Case reports and case studies were also excluded.

Literature Evaluated

TOTAL REFERENCES RETRIEVED: 64
 
EVALUATION METHOD AND COMMENTS ON LITERATURE USED: Any publication year, length of follow-up, or language was accepted with studies that were relevant to the use of LLLT for BCRL. Independent title and abstract review and a recursive search of the studies were performed. The PEDro scale was used to address the bias and quality of each study. In addition, the PEDro scores were compared to previously reported scores when available, and the use of funnel plots and/or statistical tests for bias were planned.

Sample Characteristics

  • FINAL NUMBER STUDIES INCLUDED = 9
  • TOTAL PATIENTS INCLUDED IN REVIEW = 289
  • SAMPLE RANGE ACROSS STUDIES: 10–64, although it states “8–64” on page 297
  • KEY SAMPLE CHARACTERISTICS: All subjects were adult female breast cancer survivors with BCRL. Limb volume criteria for the study participants included 200 ml or more interlimb difference, more than a 2 cm difference between limbs at multiple measure points, or % difference between limbs.

Phase of Care and Clinical Applications

PHASE OF CARE: Multiple phases of care

Results

Pooled effect sizes (ESs) and 95% confidence intervals were used with nine eligible studies with evidence levels of 2–4 compared the effectiveness of LLLT both alone or with other treatment regimens for BCRL. ESs were calculated for pain and volume of the affected upper extremity. Within-group pooled ES for volume from six studies reported a 75.7 ml volume reduction post-LLLT and a between-group pooled ES for volume from four studies of 90.9 ml reduction with treatment that included LLLT. Within-group pooled ES for pain from two studies resulted in a 13.5 mm reduction of pain using the visual analog scale ([VAS], 0–100 mm). Between-group pooled ESs for pain from two studies were not statistically significant.

Conclusions

A systematic review and meta-analysis of nine studies reported with moderate strength evidence that within-group clinically relevant limb volume reductions were greater with the use of LLLT than without immediately following LLLT. The same was reported regarding clinically relevant pain associated with BCRL. Two studies are identified as not having a comparison group, and statistical reporting varied between the studies, making the ES pooling difficult.

Limitations

  • Low sample sizes
  • Not all treatment groups received LLLT
  • Non-LLLT treatments varied
  • Laser types, application duration, and number of sessions of LLLT varied.
  • Patient characteristics, such as age and comorbidities, were not reported.
  • Varied methods of measure for limb volume were used, and only five studies included measures for pain.

Nursing Implications

It is important for nurses to understand the use of systematic reviews and meta-analyses in helping to improve evidence-based findings. Nurses can help establish clinical relevance or clinical significance benchmarks, as well as identify variables that may impact results. These findings suggest that LLLT may be helpful in the management of lymphedema; however, additional research is needed in this area.

Legacy ID

6549