Metastases to the breast: Role of fine needle cytology samples. Our experience with nine cases in 2 years

Background: The increased survival due to the introduction of effective antineoplastic regimens has caused a modification of the natural history of numerous malignancies. Follow-up of neoplastic patients often includes the evaluation of masses in various body sites by fine needle cytology (FNC) in order to rule out cancer recurrence. Besides primary neoplasms, the breast can host a number of metastases: these rarely do have a typical presentation, so FNC is requested for their cytomorphological assessment. Patients and methods: This report describes nine consecutive cases in which a cytopathological diagnosis of metastasis to the breast was carried out on FNC samples. Results: Primary sites were identified on cytomorphological and immunocytochemical bases and were represented by the ovary (three cases), melanoma (two cases), endocervix (one case), endometrium (one case), lung (one case) and prostate (one case). Conclusion: The cytopathological diagnosis of metastatic neoplasms to the breast is not always straightforward, especially in the absence of a clinical history of cancer. The usage of improved cytopathological criteria combined with immunocytochemistry may be of great diagnostic help in the identification of breast metastases.