Internal mammary nodal metastases from breast cancer detected by scintimammography

A 55-year-old woman had a lump in her left breast, which on biopsy proved to be infiltrating ductal carcinoma. She was treated with excisional biopsy and axillary dissection, and all 16 lymph nodes removed were negative for cancer. She received 60.8 Gy external beam radiotherapy to her breast and was followed by yearly mammography. Her third mammogram showed a mass. Tc- 99m MIBI scintimammography at this point showed mild to moderately increased uptake in the mass and in the anterior mediastinum. CT scanning confirmed the presence of a mediastinal mass, which fine needle aspiration cytology proved to be metastatic breast cancer. Tc-99m MIBI scintimammography helped to identify the extent of the recurrent disease in the left breast and mediastinum, which otherwise would have been undetected and the patient would have had a mastectomy.