Lobular carcinoma in situ is a form of in situ neoplasia that develops within the terminal lobules of the breast. It is an extremely rare finding in males due to the lack of lobular development in the male breast. The authors herein report an unusual case of incidentally discovered lobular carcinoma in situ in a male patient with recurrent bilateral gynecomastia who was subsequently diagnosed with invasive ductal carcinoma of the left breast. The pathology of lobular carcinoma in situ in a male as well as screening MRI surveillance of male patients at high risk for breast cancer are discussed, emphasizing the importance of screening and imaging follow up in men who are at high risk for breast cancer.
