Defining a threshold for intervention in breast cancer-related lymphedema: what level of arm volume increase predicts progression?

The purpose of this study is to evaluate arm volume measurements and clinico-pathologic characteristics of breast cancer patients to define a threshold for intervention in breast cancer-related lymphedema. We prospectively performed arm volume measurements on breast cancer patients using a Perometer. Arm measurements were performed pre- and post-operatively, and change in arm volume was quantified using a relative volume change (RVC) equation. Patient and treatment risk factors were evaluated. Cox proportional hazards models with time-dependent covariates for RVC were used to evaluate whether RVC elevations of a parts per thousand yen3 to < 5 % or a parts per thousand yen5 to < 10 % occurring a parts per thousand currency sign3 months or > 3 months after surgery were associated with progression to a parts per thousand yen10 % RVC. 1,173 patients met eligibility criteria with a median of 27 months post-operative follow-up. The cumulative incidence of a parts per thousand yen10 % RVC at 24 months was 5.26 % (95 % CI 4.01-6.88 %). By multivariable analysis, a measurement of a parts per thousand yen5 to < 10 % RVC occurring > 3 months after surgery was significantly associated with an increased risk of progression to a parts per thousand yen10 % RVC (HR 2.97, p < 0.0001), but a measurement of a parts per thousand yen3 to < 5 % RVC during the same time period was not statistically significantly associated (HR 1.55, p = 0.10). Other significant risk factors included a measurement a parts per thousand currency sign3 months after surgery with RVC of a parts per thousand yen3 to < 5 % (p = 0.007), a parts per thousand yen5 to < 10 % (p < 0.0001), or a parts per thousand yen10 % (p = 0.023), axillary lymph node dissection (ALND) (p < 0.0001), and higher BMI at diagnosis (p = 0.0028). Type of breast surgery, age, number of positive or number of lymph nodes removed, nodal radiation, chemotherapy, and hormonal therapy were not significant (p > 0.05). Breast cancer patients who experience a relative arm volume increase of a parts per thousand yen3 to < 5 % occurring > 3 months after surgery do not have a statistically significant increase in risk of progression to a parts per thousand yen10 %, a common lymphedema criterion. Our data support utilization of a a parts per thousand yen5 to < 10 % threshold for close monitoring or intervention, warranting further assessment. Additional risk factors for progression to a parts per thousand yen10 % include ALND, higher BMI, and post-operative arm volume elevation.