Case description
A 36-year-old woman was referred to our center with a painless palpable mass in the upper central portion of the left breast. She had no family history of breast cancer and no personal history of other malignancies. Ultrasonography (US) showed an approximately 3.5x3cm irregularly shaped, indistinct, hypoechoic mass with multiple ipsilateral enlarged axillary lymph nodes (Fig. 1A). Preoperative magnetic resonance imaging (MRI) showed an approximately 3.9x3.5cm irregular mass with heterogeneous enhancement and multiple enlarged axillary lymph nodes (Fig. 1B). On MRI, an irregular mass with heterogeneous enhancement was found on the upper inner quadrant of the right breast, and we recommended MR-guided US for this lesion (Fig. 2A). On MR-guided US, an approximately 1.4 x 0.4cm irregular-shaped and indistinct mass was detected that correlated to the MR lesion (Fig. 2B). US-guided core biopsies for both breast lesions and the left axillary lymph node were performed, and the pathologic results confirmed invasive ductal carcinoma in the left breast, suggested MALT lymphoma in the right breast, and confirmed metastatic adenocarcinoma in the left axillary lymph node. Although the synchronous occurrence of multiple neoplastic processes is uncommon, the possibility of synchronous breast carcinoma and primary breast lymphoma should be considered to avoid inaccurate staging and delays in diagnosis and to ensure good therapeutic and prognostic implications (1, 2).