Abstracts Background: The aim of this cross-sectional study was to investigate the volume, fat mass, and lean mass in both upper and lower limbs measured with dual-energy X-ray absorptiometry (DXA) in melanoma patients with melanoma-related limb lymphedema.

METHODS AND RESULTS: Four hundred thirty-one patients who had undergone surgical treatment with wide local excision and unilateral axillary or inguinal sentinel lymph node biopsy and/or complete lymph node dissection participated in a survey, and they underwent clinical examination and measurements of their upper or lower limbs with DXA. Limb lymphedema was diagnosed on the basis of history and characteristic physical findings on the clinical examination. The inter-limb differences in volume, fat mass, and lean mass measured with DXA were categorized as none/mild, moderate, or severe according to reference values (taking handedness into account for the upper limbs). Of the 431 patients, 109 (25%) had clinical melanoma-related limb lymphedema corresponding to 23 (10%) who had undergone axillary nodal surgery and 86 (45%) who had undergone inguinal nodal surgery. The majority of patients developed lymphedema within the first year (90%) after surgery, and the majority of lymphedemas were categorized as mild. The increase in the volume of limbs with lymphedema was primarily due to an increase in fat mass.

CONCLUSION: There is a high prevalence of melanoma-related limb lymphedema. The increase in volume in the limb with lymphedema is primarily due to an increase in fat mass. This increase in fat mass in limbs with lymphedema is important for the understanding of the pathophysiology and may be important in the treatment of lymphedema.