Abstract P1-01-14: Extracorporeal shock wave therapy for lymphedema after axillary lymphadenectomy

Introduction : Lymphedema is a frequent complication of local treatment for breast cancer. Substantial differences in the incidence of lymphedema have been reported depending on the extent of surgery, presence of lymph node metastasis and postoperative radiotherapy. The classical treatment of lymphedema includes manual lymph drainage and compressive bandages. No pharmacological treatment has been shown to be effective. In animal experiments extracorporeal shock wave therapy (ESWT) has been shown to stimulate angiogenesis and lymphatic vessel regeneration. However, whether ESWT reduces lymphedema after axillary lymphadenectomy is unknown. Patients and Method : We randomized patients with lymphedema after axillary lymphadenectomy (2004 to 2011) into a treatment and a placebo group. Informed consent was obtained from all patients. All but one patient had at least one positive lymph node. A mean of 21.9 (5-43) lymph nodes were removed. 8/10 had an adjuvant radiotherapy of the axilla. ESWT of the whole edematous limb was performed once a week for 10 weeks (2000 shots, energy density 0,25-0,69 mJ/mm 2 ). The placebo group underwent similar treatment, but the shock waves were absorbed in the probe. At baseline and at the end of treatment a clinical and oncological control was performed, including tolerability of the therapy (pain, local skin changes or infections) and oncological safety (recurrence rate). The response to ESWT was measured by volumetry (water displacement of the whole arm) and peripheral quantitative computed tomography (pQCT, change in total cross sectional area of the most swollen part of the arm). Also questionnaires on subjective body feeling, activity score and body image were applied. Results : We report the preliminary results of the first 10 patients (placebo n = 5, verum n = 5) after 10 weeks. The median change water displacement volume in the verum group corresponded to -192.5 ml (25% percentile: -366.3 ml, 75% percentile -148.8 ml) vs. -12.5 ml (25% percentile: -192.8 ml, 75% percentile: 147.5 ml) in the placebo group (p-value for Mann-Whitney U test: 0.093). Cross sectional area decreased by -3.05% (25% percentile: -8.73%, 75% percentile: 1.49%) in the verum group vs. -1.36% (25% percentile -3.47%, 75% percentile 4.20%) in the placebo group (p-value: 0.394). No treatment had to be interrupted due to local complications. Conclusion: ESWT is well tolerated in patients treated for lymphedema after axillary lymphadenectomy. Our preliminary results show a promising trend towards both objective and subjective improvement of the lymphedema. The statistical significance of these improvements has to be confirmed after inclusion of all patients (N = 30). Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-01-14.