Abstract

Hamartoma of the breast is relatively rare benign tumor, which is a well-circumscribed mass mainly composed of fibrous stroma, a(tipose tissue, ducts and acini. Muscular hamartoma of the breast is mainly composed of smooth muscle, and is extremely rare because proper smooth muscle is normaly absent in the breast except in the nipple. We describe a rare case of muscular hamartoma of the breast in a 38-year-old woman. This tumor was located in the upper outer quadrant and a 3 x 2.5 x 2 cm sized, well-demarcated but not encapsulated mass, The mass consisted mainly of irregularly arranged smooth muscle bundles in the fibrous stroma with lobular units and admixed fat cells. The origin of smooth muscle in hamartoma is not well known.

• Keywords: Muscular hamartoma;Breast