Metastasis of ovarian cancer to the breast: A report of two cases and a review of the literature.

Metastasis of ovarian cancer to the breast (MOCB) is a rare event. Clinical presentations of MOCB vary and surgery is the mainstay of treatment. The current study presents two cases of MOCB in women with recurrent ovarian cancer first diagnosed in April 2011 and October 2013, respectively. The patients presented to the clinic with a localized, palpable, painful mass in the upper outer quadrant of the right breast and a centrally localized, palpable, painful mass of the left breast, respectively. Breast sonography and mammography showed a singular, round, homogenous tumor with irregular borders in each case. An ipsilateral enlarged axillary node was palpable in one case. Tumor biopsy revealed an undifferentiated adenocarcinoma of unknown origin in one case and a moderately-differentiated adenocarcinoma suspected to be breast cancer in the other case. Tumor cells were positive for estrogen receptor and paired box 8, and negative for GATA binding protein 3 in the two cases. Palliative mastectomy was performed in one case and lumpectomy with ipsilateral axillary sentinel node biopsy in the other case, and the final histology revealed MOCB in each. The post-operative course of the disease was uneventful and the patients continued with their ovarian cancer-specific chemotherapy. One patient succumbed to disease progression 2 months after breast surgery. The other patient remains alive and is currently undergoing systemic chemotherapy. The current study also presents a review of 110 cases of MOCB identified in a literature search of Pubmed. Data from these studies, including the clinical and histological characteristics of MOCB, and the clinical management and prognosis are discussed. Overall, MOCB is rare, with distinct clinical and histological features. The disease is usually treated with local surgical excision or mastectomy and has a poor prognosis.