A new study has reported that at least 8% of breast cancer patients still have lymphedema five years and longer after surgery for breast cancer. The study was designed to investigate the prevalence of long-term breast cancer-related lymphedema, as assessed by objective and subjective measures. There exists a lack of consistency in the definition and measurement of lymphedema which contributes to the wide range of reported prevalence.

The study included 145 post-surgical breast cancer patients. The arms of the participants were evaluated for lymphedema using the water displacement method (the gold standard measurement method, according to the authors). For comparison, two arm circumference methods and patient-reported swelling were also used. The lymphedema measurements were performed at least five years after breast cancer surgery.

The prevalence of long-term lymphedema was found to be 8% using the water displacement method. The prevalence was considerably higher when other methods were used: sum of arm circumference (16%); arm circumference (31%); and patient self-report (17%). Of the women found to have long-term lymphedema using the water displacement technique, 82% were also detected using the sum of arm circumference method, 82% using the arm circumference method, and 91% by self-report. The authors comment that the prevalence of lymphedema more than five years after surgical treatment differs depending on the measuring method used. The study data underlines the necessity for consensus on the diagnostic criteria for lymphedema.