RESUMEN
BACKGROUND: Primary sarcoma of the breast is rare. Surgery has been the only curative treatment available. Recently, neoadjuvant chemotherapy including anthracycline/ifosfamide has been reported effective for patients with high-risk sarcomas in a prospective trial. CASE PRESENTATION: A 52-year-old Japanese woman presented with a mass in her left breast. The 10 cm tumor was fixed to her chest wall on examination. A skin biopsy was performed which showed leiomyosarcoma. Neoadjuvant chemotherapy was given and the tumor became mobile. A mastectomy and axillary dissection were performed with surgically negative margins. After neoadjuvant chemotherapy, the amount of necrosis was profoundly influenced by chemotherapy, and the histological effect of neoadjuvant chemotherapy was assessed in reference to pre-neoadjuvant chemotherapy magnetic resonance imaging. CONCLUSION: In contrast to many other cancers, the evaluation of various treatments and of the histological effect of neoadjuvant chemotherapy for sarcoma has been difficult due to the rarity of these tumors. We report the case of a patient with a breast sarcoma, treated with neoadjuvant chemotherapy and discuss the appropriate pathological evaluation and therapeutic management.