关键词: 印戒细胞癌, 乳腺肿瘤, 病例报告

Abstract: Objective To report a rare case of primary invasive mixed signet ring cell carcinoma （SRCBC） of the breast, and to investigate its clinical characteristics, diagnostic criteria, differential diagnosis, and treatment and prognosis for improve understanding of this rare disease. Methods Clinical data, imaging findings, pathological results （core-needle biopsy and postoperative）, and treatment course （right total mastectomy with low axillary lymph node dissection） of an 83-year-old female patient were retrospectively analyzed with a comprehensive literature review. Results The patient presented with a painless right breast mass. Preoperative imaging suggested malignancy （BI-RADS 4C）. Both biopsy and postoperative pathology confirmed invasive mixed carcinoma composed predominantly of mucinous carcinoma （90%） and signet ring cell carcinoma （>20%）, with a minor component of grade Ⅱ invasive ductal carcinoma （10%）. Immunohistochemistry demonstrated strong ER positivity （90%）, low PR expression （<5%）, Her-2 negativity, and Ki-67 （15%）, supporting mammary origin （E-Cadherin+, GATA-3+）. Axillary lymph nodes showed no metastasis （0/16）. Perioperative management integrated Traditional Chinese Medicine （herbal decoction, auricular acupuncture, micro-acupuncture） with conventional therapy （surgery + supportive care）. Metastatic disease was excluded through imaging and clinical history, confirming primary mixed SRCBC （T2N0M0）. Conclusion This mixed-pathology case exhibited relatively favorable prognosis due to early pathological stage （T2N0M0） and node-negative status.

Key words: signet ring cell carcinoma, breast tumors, case reports