Primary non-Hodgkin's lymphoma of the breast: report of a case with special reference to 380 cases in the Japanese literature.

A 52-year-old Japanese woman presented with a mass in the left breast. A tumor 2.9 cm in diameter was found in the D area on ultrasonography. An ipsilateral swollen axillary lymph node was detected. Invasion of the tumor to the pectoralis major muscle was seen. Based on a diagnosis of malignant lymphoma by fine needle aspiration cytology, radical mastectomy with ipsilateral axillary lymph node dissection was performed. Malignant diffuse large B-cell type lymphoma was diagnosed histologically according to the World Health Organization classification, and the clinical stage was II E by the Ann Arbor staging system. Four courses of adjuvant chemotherapy with cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) were subsequently performed. The patient is free of recurrence 7 years after surgery. Up to 2002, 380 cases of primary breast non-Hodgkin's lymphoma had been documented in the Japanese literature. When the tumor size was bigger than 4.5 cm, the outcome was poor. Regarding treatment methods, we showed that only enucleation of the tumor is necessary and axillary dissection is not necessary. In our case, we thought that the prognosis was good despite the large tumor and axillary lymph node metastasis, and that we could omit axillary dissection.