Breast cancer metastasis to the colon with incompatible receptors: A case report and literature review

Background The metastasis of breast cancer to the colon is a rare occurrence, especially in the presence of changes in estrogen and progesterone receptors. To date, literature has only reported three cases of invasive ductal carcinoma metastasizing to the colon with concurrent changes in hormone receptors. Case presentation : This report describes a 65-year-old female with a history of left breast cancer, who presented with symptoms of bloody stools and abdominal pain. CT and colonoscopy revealed a malignant tumor in the ascending colon, and the patient underwent surgery. Pathological results post-surgery indicated changes in hormone receptors, differing from the previous breast cancer pathology, ultimately leading to the diagnosis of breast cancer metastasis to the colon. The patient was found to have liver metastasis 14 months after surgery, and systemic metastases in various locations were discovered at the 19-month mark. Conclusions Patients with previous breast cancer should be aware of the possibility of colon metastases, even if receptor changes occur.