L-Dex, arm volume, and symptom trajectories 24 months after breast cancer surgery

Study objectives were to examine: (a) biomarker trajectories (change from presurgical baseline values of Lymphedema index (L-Dex) units and arm volume difference) and symptom cluster scores 24 months after breast cancer surgery and (b) associations of these objective biomarkers and symptom cluster scores. Patient/treatment characteristics influencing trajectories were also evaluated.

A secondary analysis of data from the published interim analysis of a randomized parent study was undertaken using trajectory analysis. Five hundred and eight participants included in the prior analysis with 24 months of postsurgical follow-up were initially measured with bioelectric impedance spectroscopy (BIS) and tape measure (TM) and completed self-report measures. Patients were reassessed postsurgery for continuing eligibility and then randomized to either BIS or TM groups and measured along with self-report data at regular and optional* visits 3, 6,12,15*,18, 21*, and 24-months.

Three subclinical trajectories were identified for each biomarker (decreasing, stable, increasing) and symptom cluster scores (stable, slight increase/decrease, increasing). Subclinical lymphedema was identified throughout the 24-month period by each biomarker. An L-Dex increase at 15 months in the BIS group was noted. The self-report sets demonstrated contingency coefficients of 0.20 (LSIDS-A soft tissue, P = .031) and 0.19 (FACTB+4, P = .044) with the L-Dex unit change trajectories.

These data support the need for long-term (24 months) prospective surveillance with frequent assessments (every 3 months) at least 15 months after surgery. Statistically significant convergence of symptom cluster scores with L-Dex unit change supports BIS as beneficial in the early identification of subclinical lymphedema.