Esophageal Diseases

Esophageal diseases largely include gastroesophageal reflux disease (GERD), motility disorder, and esophageal cancer. GERD is categorized into erosive or reflux esophagitis (RE), which causes damage to the esophagus, and nonerosive reflux disease (NERD), which provokes severe GERD symptoms without damaging the esophagus at all. There are sex/gender differences in the prevalence, disease mechanism, symptoms, and responses to medication of these two diseases. The prevalence of RE is 3.61 times higher in males than in females, while that of NERD is 1.34 times higher in females than in males. The higher prevalence of RE is originated from structural factors such as the lower esophageal sphincter (LES), the attenuated anti-inflammatory effect of estrogen that protects the esophageal mucosa cells, and the under-expression of tight junction proteins. Esophageal motility disorders are relatively rare diseases caused by imbalances between excitatory and inhibitory nerves of the esophagus. The prevalence of achalasia and lower esophageal hypermotility disorders is slightly higher in females. The frequency of chest pain is higher in female achalasia patients, and the LES pressure is higher in male achalasia patients. Esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC) are the two most common histopathological cell types of esophageal cancer (EC). There is a marked male predominance of EAC with a male-to-female ratio in incidence of up to 9:1. In case of ESCC, the ratio is known to be 2–3:1. In addition, EAC is more common in Western countries, but ESCC is the dominant-type of EC worldwide, particularly in East Asia and Africa.