Esophageal Carcinoma

Overview
  • Esophageal Carcinomas can be squamous cell carcinomas or adenocarcinomas. Both have similar clinical features but result from distinct etiological mechanisms.
Etiology
  • Esophageal Squamous Cell Carcinomas (SCCs)
    • Esophageal SCCs likely arise from a complex etiology related to diet, environmental factors, and genetic predisposition. Special risk factors include use of chemical irritants such as tobacco and alcohol; consequently, esophageal SCCs are more common among smokers and alcohol abusers.
  • Esophageal Adenocarcinoma
    • The only recognized pathogenic cause of esophageal adenocarcinoma is the prolonged presence of GERD. It is thought that the esophageal epithelium first undergoes metaplasia associated with Barrett Esophagus and ultimately neoplastically progresses to a full-blown adenocarcinoma.
Epidemiology
  • Esophageal Squamous Cell Carcinomas (SCCs) are much more prevalent worldwide, especially in parts of Asia and the Middle East such as China and Iran, and account for nearly 90% of total esophageal carcinomas. Esophageal Adenocarcinomas are slightly more prevalent in the US and follow the demographic patterns of Barrett Esophagus with higher prevalence among adult men, especially whites.
Morphology
  • Gross Appearance:
    • Both esophageal SCCs and adenocarcinomas begin as raised patches evolving into ulcerating masses jutting into the esophageal lumen. Ultimately, the esophageal wall is infiltrated and neoplastic cells typically spread locally to nearby structures and lymphatically to local lymph nodes. Esophageal SCCs typically appear in the upper two-thirds of the esophagus. In contrast, esophageal adenocarcinomas usually occur in the lower two-thirds of the esophagus, consistent with the role of GERD in the pathogenesis of this subtype.
  • Histological Appearance:
    • Esophageal Adenocarcinoma displays gastric epithelium-like cells that grow in a glandular pattern and are mucin-producing similar to their likely histological preprocessors encountered in Barrett Esophagus.
Clinical Consequences
  • Regardless of subtype, esophageal carcinomas typically run a course of progressive dysphagia and weight loss. Mortality is fairly high because symptomology becomes overt only when cancer has spread significantly.