Abstract P3-09-09: Comparison of multi-frequency bioimpedance with perometry for the early detection of lymphoedema after axillary node clearance

Abstract

Abstract Introduction Women who undergo axillary clearance are at risk of developing lymphoedema. Early detection is recommended by arm volume measurements from a baseline before surgery but the optimal test is unclear. This prospective multi-centre study compares multi-frequency bioimpedance spectroscopy (BIS, ImpediMed) with the validated perometer method to determine which test is more sensitive for detecting lymphoedema within 24 months of surgery. Results from 441 women with up to six months follow-up are reported here to determine whether the timing of arm measurement affects results. Methods Participants (N = 441) undergoing Axillary Clearance underwent pre-operative and subsequent regular measurements post-surgery (1, 3, 6, 9 & 12 months, then 6 monthly), of arm volume by perometry and BIS measurements as well as self-reported symptoms of swelling, numbness or heaviness. The primary endpoint of lymphoedema was defined as ≥10% increase in volume compared to the contralateral arm by perometry. Results We report the data from 441 patients with 6 month follow-up data, their median age is 55 years ranging from 27 to 90 years. Eighty percent of patients were ER positive and received endocrine therapy as well as surgery. Eighty percent also underwent radiotherapy to the breast or chest wall, while 70% received chemotherapy in addition to surgery. Mean percentage increase in arm volume by perometry at 6 months was 2.03% with a moderate correlation between perometry and BIS at 3 months (r = 0.38) and 6 months (r = 0.37). In 441 patients with 6 months follow-up, the gold standard perometry detected lymphoedema in 44 (10%) patients by 6 months compared to the contralateral arm, whereas BIS measured using the unit L-Dex was positive (showed an increase of an L-Dex of 10) in 103 (21%) patients. Of the 99 patients with 18 months follow-up, 24% have lymphoedema as detected by perometry. When compared with the baseline measurements for perometry and BIS, the month 1 measurements detected fewer cases of lymphoedema by 6 months, 11 (42%) fewer for perometry and 18 (30%) fewer for BIS. 25% of patients reported symptoms before surgery. While 100% of those with lymphoedema at 6 months post-surgery reported symptoms, 23% with no lymphoedema also reported at least one symptom at 6 months. Conclusions Pre-operative measurements should be used as baseline to enable accurate monitoring of lymphoedema development. Symptoms alone are not an accurate predictor of current or future lymphoedema and arm sleeves should not be prescribed for symptoms without measuring arm volume change compared to the contralateral arm. The modest correlation between perometry and BIS at 6 months suggests arm volume measurements remain necessary before and after ANC for monitoring, although longer term follow-up data is required to determine the most sensitive method of predicting lymphoedema.(Funded by NIHR Programme Grant). Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-09-09.