Early diagnosis of lymphedema using multiple frequency bioimpedance

Multiple frequency bioelectrical impedance analysis (MFBIA) has previously been shown to provide accurate relative measures of lymphedema in the upper limb of patients (1). This paper reports the results of a three year prosp ective study to evaluate the efficacy of MFBIA to predict the early onset o f lymphedema in patients following treatment for breast cancer. Bioelectrical impedance measurements and circumferential measurements of ea ch upper limb were recorded in healthy control subjects (n=60) to determine the normal range of the ratio (dominant/non-dominant) of extracellular and total limb volumes respectively. Patients undergoing surgery for the treat ment of breast cancer were recruited as the study group; MFBIA and circumfe rential measurements were recorded pre-surgery, one month post-surgery and then at two month intervals for 24 months. One hundred and two patients were recruited into the study. Twenty patients developed lymphedema in the 24 months follow up period of this study. In e ach of these 20 cases MFBIA predicted the onset of the condition up to 10 m onths before the condition could be clinically diagnosed. Estimates of the sensitivity and specificity were both approximately 100%. At the time of de tection by MFBIA, only one of the patients returned a positive test result from the total limb volumes determined from the circumferential measures. T hese results confirmed the suitability of the MFBIA technique as a reliable diagnostic procedure for the early detection of lymphedema.