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

摘要： 目的 报告一例罕见的乳腺原发性浸润性混合型印戒细胞癌（SRCBC）,探讨其临床特征、诊断要点、鉴别诊断及治疗预后,以提高对该罕见疾病的认识。方法 回顾性分析1例83岁女性患者的临床资料、影像学检查、病理结果（穿刺及术后）及治疗过程（右乳全切+低腋窝淋巴结清扫术）,并结合文献进行复习。结果 患者以右乳无痛性肿块就诊。术前影像学提示恶性（BI-RADS 4C类）,穿刺及术后病理均证实为浸润性混合型癌,主要由黏液癌（90%）及印戒细胞癌（>20%）组成,伴少量浸润性导管癌Ⅱ级（10%）。免疫组化示ER强阳性（90%）、PR低表达（<5%）、Her-2阴性、Ki-67（15%）,支持乳腺原发（E-Cadherin+, GATA-3+）。腋窝淋巴结未见癌转移（0/16）。围术期采用中西医结合治疗（手术+常规支持治疗+中药+耳针/微针）。影像学及病史排除转移性可能,最终诊断为原发性混合型SRCBC（T2N0M0）。结论 本例表现为混合病理类型,术后病理分期较早且无淋巴结转移,预后相对较好。

关键词: 印戒细胞癌, 乳腺肿瘤, 病例报告