Diagnosis of Early and Subclinical Lymphedema Following Breast Cancer

There is an established and growing belief that noninvasive monitoring can detect the presence of the earliest stages of breast cancer-associated lymphedema, and thereby favorably alter the severity and natural history of this vexing disorder.^1–3 Bioimpedance spectroscopy (BIS) is a tool that has been developed and proposed for its sensitivity to the early, ipsilateral accumulation of extracellular fluid in the at-risk limb following breast cancer therapeutics. ⁴

Widespread adoption of BIS for the monitoring of breast cancer-associated lymphedema has been hindered by the lack of published normative values, both for the pretreatment upper-extremity bioimpedance ratios and, descriptively, the longitudinal patterns of change during the high-risk first twelve months that follow the surgical intervention. ⁵

In the current issue of Lymphatic Research and Biology, Ridner and colleagues seek to address these deficiencies. They conducted a study of 280 such patients, with the requirement that a pretreatment, and at least one posttreatment, assessment of bioimpedance ratios were available for analysis. Pretreatment L-Dex readings were compared to population norms, and maximum changes within 12 months were examined. From this work, the authors have concluded that, at the time of breast cancer diagnosis, the values for bioimpedance ratios are similar to normative values. Furthermore, identified maximum changes in these values at 12 months suggest that frequent assessment during this index year provides potential benefit. Finally, their work suggests that an even lower threshold than conventionally held might be considered to establish the presence of subclinical lymphedema.