We read the original article by Dominici et al 1 regarding the complete eradication of axillary lymph node metastases in patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer who were treated with trastuzumab-containing neoadjuvant chemotherapy. The exquisite sensitivity of breast cancer to this treatment may generate an axillary lymph node complete pathological response that, as a counterpart, causes the stromal and vascular changes that give rise to the appearance of lymphedema before surgery. A patient aged 48 years was diagnosed with an invasive ductal carcinoma of the left breast with positive estrogen receptors, negative progesterone receptors, and positive HER2 in clinical stage IIIB (T4bN2M0). She was treated with four 21-day cycles of doxorubicin at a dose of 60 mg/m 2 and cyclophosphamide at a dose of 600 mg/m 2 , both administered intravenously. After the fourth cycle, the patient developed left arm lymphedema. Venous thrombosis was discounted by Doppler ultrasound. The patient completed the neoadjuvant treatment with four 21-day cycles of docetaxel at a dose of 100 mg/m 2 and trastuzumab at a dose of 6 mg/kg (8-mg/kg loading dose), both administered intravenously. During this treatment, the clinical remission of the mammary and axillary disease was maintained, and the edema of the arm increased. The histopathological result of modified radical mastectomy was the total absence of tumor, and marked postchemotherapy changes. During the axillary lymphadenectomy, only 3 lymphatic ganglia were recognized, all of which were free from metastasis, with interstitial fibrosis and lymphoid depletion. Also recognized were several foci of fibrosis with a scarce lymphoid population, suggestive of pre-existing lymphatic ganglia with changes produced by the chemotherapy.To the best of our knowledge, there are no descriptions in the literature of the appearance of lymphedema in this context.