Rare tumors of esophageal squamous mucosa. 
In spite of increasing incidence of esophageal adenocarcinoma in the last few decades, esophageal squamous cell carcinoma (SCC) still remains the dominant subtype of esophageal cancer worldwide.  Apart from conventional SCC, some rare unconventional tumors of esophageal squamous mucosa are also well known.  This study provides an introduction to these and presents a brief review of the literature, including the diagnostic and prognostic importance of each variant.