The significance of reducing upper limb fat content in improving breast cancer-related upper limb lymphedema

Problem Considered To investigate the potential association between reducing upper limb body fat content through nutritional guidance and breast cancer-related upper limb lymphedema improvement. Methods A retrospective study was carried out on patients with breast cancer-related upper limb lymphedema who underwent nutritional guidance from June 2016 to December 2018, aiming to explore the potential correlation between alterations in body fat mass and the improvement of lymphedema. Results Following nutritional guidance, patients exhibited a significant reduction in both body mass index (BMI) and total body fat mass (p < 0.05). Although there was no significant change in the circumference of the affected forearm, the extracellular water ratio demonstrated a non-significant declining trend. Exploratory analysis indicated that the group with relatively notable lymphedema improvement experienced a more pronounced reduction in body fat mass on the healthy side (p = 0.049), and a positive correlation was observed between changes in body fat mass on the healthy side and the improvement of lymphedema on the affected side (p = 0.013). However, these subgroup analyses are data-driven and exploratory, and their findings should be interpreted with caution due to the risks of multiplicity and false-positive results; they require validation in prospective studies. Conclusion Weight reduction through nutritional guidance may be associated with alleviation of lymphedema, particularly as the reduction in body fat mass on the healthy side appeared to correlate with lymphedema improvement in exploratory analyses. In addition to routine lymphedema evaluation, measuring body fat mass on the healthy side could be explored as a supplementary indicator for assessing the effectiveness of nutritional guidance in future studies.