Esophageal cancer

Esophageal cancer typically assumes the form of adenocarcinoma or squamous cell carcinoma, although there are some rarer tumors. Adenocarcinomas are considered the fastest-growing neoplasia in Western countries, while squamous cell carcinoma is still most common in the developing world. Adenocarcinoma, which usually affects the lower third of the esophagus, may be preceded by Barrett's esophagus, a complication of gastroesophageal reflux disease (GERD). In addition to GERD, other risk factors include obesity and smoking. Squamous cell carcinomas mostly occur in the upper two-thirds of the esophagus. Known risk factors for squamous cell carcinoma include carcinogen exposure from alcohol and tobacco consumption, and dietary factors (e.g., diet low in fruits and vegetables). Esophageal cancers are often asymptomatic in early stages of the disease. Locally advanced disease is common at presentation, progressive dysphagia being the primary symptom. Hoarseness, weight loss, and hematemesis may also be present. Endoscopy is the primary diagnostic test, enabling direct visualization and biopsy of the lesion for histopathological confirmation. Curative surgical resection may be considered for locally invasive cancers. Esophageal cancer is unresectable at presentation in about 60% of patients. Chemotherapy, radiation, and palliative stenting play a role in the management of unresectable disease.

• Sex: ♂ > ♀ (3:1)
• Peak incidence: 60–70 years of age
• Adenocarcinoma: most common type of esophageal cancer in the US ^[1]
• Squamous cell carcinoma (SCC): most common type of esophageal cancer worldwide ^[2]

Adenocarcinoma is more common in the US of America.

References:^[1][2][3]

Epidemiological data refers to the US, unless otherwise specified.

Adenocarcinoma

• Risk factors
  • Gastroesophageal reflux: Barrett's esophagus
  • Obesity
  • Smoking
  • Achalasia
• Localization: mostly in the lower third of the esophagus

Squamous cell carcinoma (SCC)

• Risk factors ^[4]
  • Alcohol consumption
  • Smoking
  • Diet low in fruits and vegetables
  • Drinking hot beverages
  • Achalasia
  • Nitrosamines exposure (e.g., cured meat, fish, bacon) ^[5]
  • Plummer-Vinson syndrome
  • Caustic strictures
  • Diverticula (e.g., Zenker's diverticulum)
  • Radiotherapy
  • Esophageal candidiasis
  • Betel or areca nut chewing
• Localization: mostly in the upper two-thirds of the esophagus

The primary risk factors for squamous cell esophageal cancer are alcohol consumption, smoking, and dietary factors (e.g., diet low in fruits and vegetables)!

References:^[4][6]

• Early stages: Often asymptomatic but may present with swallowing difficulties or retrosternal discomfort
• Late stages
  • Common
    • Progressive dysphagia (from solids to liquids) with possible odynophagia
    • Weight loss
    • Retrosternal chest or back pain
    • Anemia
  • Less common
    • Hematemesis, melena
    • Hoarseness

Esophageal cancer is a "silent" disease and typically becomes symptomatic at advanced stages!

References:^[3][6][7][8]

• Esophagogastroduodenoscopy (best initial and confirmatory test) ^[8]
  • Direct visualization of the tumor
  • With biopsy of any suspicious lesions
• Barium swallow: asymmetrical and irregular borders of the esophagus with characteristic stenosis and proximal dilatation (apple core lesion)
  • Sensitive, but does not allow confirmation or staging of a malignancy. Inferior to endoscopy, but indicated in the case of:
    • Severe stricture that inhibits endoscopic evaluation
    • Suspected tracheoesophageal fistula due to esophageal cancer
• Staging ^[8]
  • Transesophageal endoscopic ultrasound
  • Chest and abdominal CT; and/or PET
  • Bronchoscopy or laparoscopy

References:^[2][3][8][9]

Adenocarcinoma

• Histological characteristics: often present with adjacent Barrett mucosa; (columnar epithelium with goblet cells) and high-grade dysplasia

Squamous cell carcinoma

• Histological characteristics
  • Breakdown of uniform tissue structure
  • Squamous cell carcinoma clusters with circular keratinization
  • Lymphocytic infiltration between the carcinoma clusters

Curative

• Indication
  • Locally invasive disease that has not invaded surrounding structures
  • High-grade metaplasia in Barrett syndrome
• Methods
  • Neoadjuvant chemoradiation
    • For downstaging → potentially allows for later resection
    • As definitive treatment in patients with proven complete response (e.g., during endoscopy)
  • Surgical resection
    • Endoscopic submucosal resection for removal of superficial, epithelial lesions
    • Subtotal or total esophagectomy with gastric pull-through procedure or colonic interposition

Palliative

• Indication: patients with advanced disease (majority of patients)
• Methods:
  • Chemoradiation
  • Stent placement
  • Other endoscopic treatments (e.g., laser therapy)

References:^{[1][3][9][10][11][12][13]}

• Esophageal stenosis
• Tracheoesophageal fistula: passage of food and fluid into the respiratory tract
• Postoperative
  • Anastomotic leak or stricture
  • Recurrent laryngeal nerve injury

References:^{[6][9][13][14]}

We list the most important complications. The selection is not exhaustive.

• Generally poor prognosis due to an aggressive course (due to an absent serosa in the esophageal wall) and typically late diagnosis ^[1][8]
• The more distal the tumor, the better the prognosis

Esophageal cancer has an aggressive course and metastasizes early because of the absence of serosa in parts of the esophagus!References:^[1][8]