Haematogenous metastases of breast cancer tumors has previously been demonstrated to frequently occur at the sites of the lung, bones, liver and brain, however presence in the uterine remains a rare occurrence. Metastatic carcinoma of the uterus usually originates from other genital sites, most frequently from the ovaries. The current review presents the first reported case of lobular breast carcinoma metastasizing to an endometrial polyp, the cervix and a leiomyoma simultaneously. The patient (58 years, female) first presented with abnormal uterine bleeding. Invasive ductal carcinoma had previously been diagnosed in her right breast, with lobular and ductal cancer cells observed to be present in her lymph nodes. A hysteroscopic procedure to examine the postmenopausal bleeding revealed an endometrial polyp, which was subsequently resected. The morphology and immunohistochemical studies confirmed the diagnosis of metastasis of lobular breast carcinoma to an endometrial polyp. An 18F fludeoxyglucose positron emission tomography/computed tomography (PET-CT) scan performed following the diagnosis, revealed a slightly increased uptake in the myoma, which is often observed in benign uterine leiomyoma. The patient then underwent a total abdominal hysterectomy with bilateral salpingo-oophorectomy and partial colectomy. Pathology results demonstrated that the uterine leiomyoma and cervix shared the same histopathological features as those presented by the primary lobular breast carcinoma. Although rare, breast tumors may metastasize to an endometrial polyp, cervix and leiomyoma concurrently in patients, therefore physicians may now consider the potential of the diagnosis of metastatic spread to the genital tract, in a patient with abnormal uterine bleeding and a history of lobular breast cancer. Gynecologists planning a laparoscopic hysterectomy for a patient with a history of lobular breast carcinoma may consider abdominal rather than laparoscopic hysterectomy, as lobular carcinoma is difficult to detect. The use of PET-CT may be beneficial for the identification of an unexpected mass.
Keywords: breast cancer; endometrial polyp; leiomyoma; metastasis.