Infantile Myofibroma

**Semantic type:** Neoplastic Process

**Definition:** A benign, localized, nodular and well-circumscribed neoplasm seen as a congenital neoplasm or in the first year of life. It is characterized by a biphasic growth pattern and is composed of small, undifferentiated mesenchymal cells associated with branching thin-walled vessels and more mature neoplastic spindle cells with abundant eosinophilic cytoplasm in a collagenous stroma.

**Synonyms:** - Infantile Hemangiopericytoma