Metastasis of Invasive Ductal Carcinoma of the Breast to the Uterine Cervix 30 Years Post‐Mastectomy: A Case Report

ABSTRACT

Metastasis of invasive ductal carcinoma of the breast to the uterine cervix is rare, with only one report of a case occurring more than 20 years after the primary surgery. A 69‐year‐old woman presented with abnormal uterine cervical cytology (atypical glandular cells without tumor diathesis) 30 years after undergoing breast cancer surgery. Magnetic resonance imaging revealed a 38‐mm cervical mass. Modified radical hysterectomy was performed. The resected specimen exhibited an immunohistochemical profile of GATA3(+)/mammaglobin(+)/PAX8(−), which definitively excluded primary cervical adenocarcinoma and confirmed the diagnosis of metastatic invasive ductal carcinoma. Crucially, although the primary tumor was hormone receptor‐positive, cervical metastasis exhibited receptor conversion to HER2‐positive status. This case underscores the importance of considering metastatic breast cancer in the differential diagnosis of cervical masses in breast cancer survivors regardless of the disease‐free interval. This further highlights the necessity for receptor re‐evaluation in metastatic lesions to guide appropriate targeted therapy.