Tissue Composition Changes and Secondary Lymphedema

Background: The aim of this study was to determine the impact of dominance and severity on tissue composition changes with lymphedema using dual-energy X-ray absorptiometry (DXA), and to determine the relationships between the DXA-determined tissue volumes and the clinical outcomes determined by perometry and bioimpedance spectroscopy. Methods and Results: Fifty-six women with secondary lymphedema and 44 women without a history of breast cancer or lymphedema underwent measurement of their upper limbs with DXA, perometry, and bioimpedance spectroscopy. Whether the affected side was the dominant or nondominant arm influenced inter-limb tissue volumes differences (F=16.31 to 35.14; all p<0.001) and interacted with the severity of lymphedema (F=3.22 to 11.07; all p<0.05). In the control group, the dominant limb had more lean tissue but less fat than the nondominant limb. In the lymphedema group, increases in fat in the affected arm were not related to generalized increases in whole body adiposity when the dominant arm was affected. Perometry-measured volumes and BIS ratios were moderately to highly correlated with inter-limb fat, volume, and total tissue differences found by DXA (r=0.39 to 0.86). Conclusions: The direction and magnitude of limb composition changes in those with lymphedema are impacted by whether the affected side is the dominant or nondominant limb, as well as the severity of the condition. The stage of tissue composition change may impact on the diagnosis and monitoring as well as treatment of secondary lymphedema.