Chordoma

**Semantic type:** Neoplastic Process

**Definition:** A low-grade malignant neoplasm that arises from the remnants of the fetal notochord. It affects almost exclusively the axial skeleton (skull and spine) and very rarely the appendicular skeleton and soft tissue. Although it can occur at all ages, it is more frequently seen in middle-aged adults. It tends to recur and may metastasize. The most common sites of metastasis are lung, bone, lymph nodes, and subcutaneous tissue.

**Synonyms:** - CHORDOMA, MALIGNANT - Chordoma, NOS - chordoma