Adipose Tissue Dominates Chronic Arm Lymphedema Following Breast Cancer: An Analysis Using Volume Rendered CT Images

Abstract

BACKGROUND: Arm lymphedema is a common complication after breast cancer treatment. Various types of conservative and surgical treatments have aimed at reducing the arm swelling, but most of these have failed due to chronic edema eventually being transformed from an accumulation of lymph fluid to an increased deposition of subcutaneous fat (i.e., to a nonpitting lymphedema). Liposuction is a safe and reliable method for reducing the excess fat without recurring deposition of it. The objective of the present study was to obtain empirical evidence confirming clinical observations of the presence of excess adipose tissue in patients with chronic nonpitting arm lymphedema following breast cancer. METHODS: A total of 11 women with nonpitting unilateral postmastectomy arm lymphedema were investigated and were treated as follows: The patient's excess arm volume was measured by plethysmography (PG) and, following treatment by liposuction, was observed until complete reduction of the excess volume was achieved. Volume-rendered CT images (VR-CT) and PG were used to analyze arm volumes and excess volume of the lympedematous arm, the respective volumes being compared by use of regression analysis. Liposuction aspirate was analyzed in terms of the distribution of adipose tissue and free fluid (lymph). The aspirate volume (total and fat fraction) was compared both with the excess arm volume measured by VR-CT and PG, and with the excess fat volume measured by VR-CT. The amount of excess adipose tissue in the lymphedematous arm was estimated using VR-CT. RESULTS: A complete reduction of the excess arm volumes, as measured with PG, was achieved within 6 months, with a mean reduction of 109%, the treated arm thus becoming somewhat smaller than the normal one. Correlations in terms of correlation coefficient (CC) and the coefficient of regression (CR) were all close to 1: The preoperative PG and the VR-CT analyses of (a) the swollen arms of the patients and (b) the excess volume; the total aspirated volume, and the excess volume of the arm, the aspirate fat volume, and the excess fat volume. The aspirate removed under bloodless conditions, achieved by use of a tourniquet, contained 93% adipose tissue. VR-CT was able to estimate the amount of excess adipose tissue in the lymphedematous arm, showing a mean excess amount of fat of 81%. CONCLUSION: VR-CT measurements correlate well with PG measurements. Excess adipose tissue dominates nonpitting chronic arm lymphedema. This excess volume cannot be removed by use either of conservative regimens or of microsurgery. Liposuction can completely remove the excess adipose tissue, leading to complete reduction of the lymphedema.