Miller, C.L., Specht, M.C., Skolny, M.N., Horick, N., Jammallo, L.S., O’Toole, J., Taghian, A.G. (2014). Risk of lymphedema after mastectomy: Potential benefit of applying ACOSOG Z0011 protocol to mastectomy patients. Breast Cancer Research and Treatment, 144, 71–77. 

DOI Link

Study Purpose

To evaluate the rate of lymphedema occurrence in patients who recieved a mastectomy and a sentinel lymph node biopsy (SLNB) with radiation therapy (RT) compared to an axillary lymph node dissection (ALND) with or without RT, with a secondary purpose to identify risk factors for development of lymphedema

Intervention Characteristics/Basic Study Process

Mastectomies were categorized into four treatment groups: SLNB without RT, SLND with RT, ALND without RT, and ALND with RT. RT included the chest wall with or without supraclavicular or axillary radiation. Measurements were obtained pre- and postoperatively, during treatment for breast cancer, and at follow-up visits after the completion of breast cancer treatment.

Sample Characteristics

  • N = 627  
  • MEDIAN AGE = 50 years (range = 22–85 years)
  • FEMALES: 100%
  • KEY DISEASE CHARACTERISTICS: Individuals who underwent mastectomies after a diagnosis of primary breast cancer between September 2005 and February 2013.

Setting

  • SITE: Single-site  
  • SETTING TYPE: Not specified  
  • LOCATION: Massachusetts General Hospital in Boston, United States

Phase of Care and Clinical Applications

  • PHASE OF CARE: Multiple phases of care

Study Design

Pre/post design with repeated measures

Measurement Instruments/Methods

  • A perometer was used to measure arm volume.
  • Weight-adjusted arm volume change (WAC) was used to detect arm volume change in each arm individually.
  • Lymphedema was defined as a measurement of ≥ 10% WAC.

Results

Of 664 mastectomies, 52% (343/664) were SLNB without RT, 5% (34/664) were SLNB with RT, 9% (58/664) were ALND without RT, and 34% (229/664) were ALND with RT. The two-year cumulative lymphedema incidence was 10% (95%, CI = 2.6%–34.4%) for SLNB with RT compared to 19.3% (95%, CI = 10.8%–33.1%) for ALND without RT and 30.1% (95%, CI = 23.7%–37.8%) for ALND with RT. The lowest cumulative incidence was 2.19% (95%, CI = .88%–5.40%) for SLNB without RT.
 
By multivariate analysis, factors significantly associated with increased lymphedema risk included RT (p = .0017), ALND (p = .0001), greater number of lymph nodes removed (p = .0006), no reconstruction (p = .0418), higher body mass index (p < .0001), and older age (p = .0021).

Conclusions

Avoiding completion ALND and receiving SLNB with RT may decrease lymphedema risk in patients requiring a mastectomy. This study indicates that the application of the American College of Surgeons Oncology Group's Z0011 treatment protocol may reduce the risk of lymphedema for patients who receive a mastectomy.

Limitations

  • Risk of bias (no random assignment)
  • Key sample group differences that could influence results
  • Other limitations/explanation: The group that received SLNB without RT was small (n = 34). Less than half (44%) of patients who received SLNB without RT had a positive SLNB. This was a single-site study.

Nursing Implications

The study provides nurses with information about SLNB with RT and how its use may decrease the risk of developing lymphedema compared to patients who recieve ALND. However, the nonrandomized, controlled trial design and the different sample sizes of each study group limit the ability to generalize this study's findings. Future randomized, controlled studies are warranted.