Esophageal Carcinoma Cuniculatum

**Semantic type:** Neoplastic Process

**Definition:** An extremely rare, well-differentiated squamous cell carcinoma that arises from the esophagus. It is characterized by the presence of hyperkeratosis, acanthosis, dyskeratosis, keratin-filled cysts, koilocyte-like cells, intraepithelial neutrophils, and focal cytologic atypia.