Stage 2 secretory breast cancer: surgery alone with clear margins

What happened, in summary

This 47-year-old woman sought care after 1 month of bloody discharge from the right breast. Examination found a solid 2 × 1 cm lump beneath the areola, with no palpable axillary lymph nodes. Sonomammography showed two well-defined thick-walled cystic lesions in the retro-areolar region of the right breast, measuring 1.5 × 1.6 cm and 1.7 × 2.6 cm, and the finding was classified as BI-RADS 4. Excisional biopsy was performed. Microscopy showed cystic change, inflammatory cells, microcystic, glandular, and solid-nest tumor patterns, and atypical duct cells. Immunohistochemistry confirmed low-grade secretory carcinoma. ER was positive, while PR and HER2/neu were negative. Additional stains supported the diagnosis, including PAS positivity, S-100 positivity, weak variable GATA3, focal weak SOX10, p63 loss around the tumor cells, CD117 negativity, and Ki-67 of 16% to 18%. Contrast-enhanced CT did not show metastasis in the chest or abdomen and mainly showed postoperative changes in the right periareolar area. She then underwent modified radical mastectomy with axillary lymph-node dissection. The tumor measured 3 × 2 × 2 cm in the surgical specimen, margins were negative, and all level 1 and 2 axillary lymph nodes were free of tumor. The final pathologic stage was pT2pN0 / Stage II. No adjuvant chemotherapy, radiation, endocrine therapy, or targeted therapy was documented. Because secretory carcinoma is rare and can look cystic on imaging, the excisional biopsy and full immunohistochemistry were central to diagnosis. At 1-month follow-up, she had no surgical site infection, no arm lymphedema, no scapular winging, and full shoulder range of motion.