The clinical features of a patient with a primary lymphoma of the breast are herein reported. The diagnosis was reached by histological examination after outpatient surgery. Surgical resection was followed by cytostatic treatment and locoregional radiotherapy. This case report is an example where the integration of physical and mammographic examination together with ultrasonography (and cytology), in the context of diagnostic procedures, induced us to perform a surgical excision on an outpatient basis. This line of action allowed us, in one step, to arrive at both the definitive diagnosis and the appropriate choice of therapy. Thus we believe that this diagnostic procedure should be carried out whenever a breast lesion, thought to be "probably benign", is found by physical or mammographic exam in a peri-postmenopausal woman.