Stage IIIA encapsulated papillary breast carcinoma with invasion: mastectomy, axillary dissection, and anastrozole

What happened, in summary

A 73-year-old woman came to the hospital with a growing mass in her right breast. She had undergone drainage of a subcutaneous abscess in the lower outer quadrant 9 years earlier and had noticed a mass in the same area for about 2 years. On exam, doctors felt a 35-mm mass in the lower inner quadrant and a 30-mm mass under the old scar. Mammography showed linear calcifications and a lobulated lower-breast mass. Ultrasound and MRI showed extensive cystic disease in the breast and multiple cystic enlarged axillary lymph nodes. A first needle biopsy of a lower-outer cystic mass showed only fibrous tissue, but a second biopsy of an upper-outer mass diagnosed invasive ductal carcinoma that was ER-positive, PgR-positive, and HER2 1+. Axillary cytology showed atypical epithelial cells suspicious for malignancy. Clinically, she was staged cT2N1M0, Stage IIB. She underwent right mastectomy and level I axillary lymph-node dissection. Final pathology showed encapsulated papillary carcinoma with invasion: a 70 x 60 x 20 mm cyst-like papillary lesion with internal hemorrhage, surrounded by a 30 x 17 x 10 mm area of invasive ductal carcinoma. Five of 19 lymph nodes were positive, and the nodal metastases had cystic papillary features resembling the primary lesion. Final stage was pT2N2aM0, Stage IIIA. Biomarkers were ER 100%, PgR 80%, HER2 2+ with FISH negative, and Ki-67 20%. Considering age, nuclear grade 1, and hormone-receptor-positive disease, postoperative treatment was anastrozole alone, without chemotherapy or radiation. At 18 months after surgery, no apparent recurrence had been observed.