Rectal Undifferentiated Carcinoma

**Semantic type:** Neoplastic Process

**Definition:** An invasive malignant epithelial tumor that arises from the rectum. There is no morphologic, immunophenotypic, or molecular biological evidence of glandular or squamous differentiation.

**Synonyms:** - Anaplastic Carcinoma of Rectum - Anaplastic Carcinoma of the Rectum - Carcinoma Simplex of the Rectum. - Rectal Anaplastic Carcinoma - Undifferentiated Carcinoma of Rectum - Undifferentiated Carcinoma of the Rectum - Undifferentiated Rectal Cancer - Undifferentiated Rectal Carcinoma