Esophageal cancer usually begins in the cells that line the inside of the esophagus. Esophageal cancer can occur anywhere along the esophagus, but in people in the United States, it occurs most often in the lower portion of the esophagus. More men than women get esophageal cancer. It’s not clear what causes esophageal cancer. Esophageal cancer occurs when cells in the esophagus develop mutations in their DNA. The mutations cause cells to grow and divide out of control. The accumulating abnormal cells form a tumor in the esophagus that can grow to invade nearby structures and spread to other parts of the body.

Esophageal cancer isn’t common in the United States. In other areas of the world, such as Asia and parts of Africa, esophageal cancer is much more common.

Incidence and Etiology

Cancer of the esophagus is a relatively uncommon but extremely lethal malignancy. The diagnosis was made in 16,980 Americans in 2011 and led to 14,710 deaths. In North America and Western Europe, the disease is more common in blacks than whites and in males than females. It appears most often after age 50 and seems to be associated with a lower socioeconomic status.

Some Etiologic Factors believed to be associated with esophageal cancer:

• Excess alcohol consumption

• Cigarette smoking

• Having bile reflux

• Chewing tobacco

• Having difficulty swallowing because of an esophageal sphincter that won’t relax (achalasia)

• Drinking very hot liquids

• Eating few fruits and vegetables

• Eating foods preserved in lye, such as lutefisk, a Nordic recipe made from whitefish, and some olive recipes

• Having gastroesophageal reflux disease (GERD)

• Being obese

• Having precancerous changes in the cells of the esophagus (Barrett’s esophagus)

• Undergoing radiation treatment to the chest or upper abdomen

Other ingested carcinogens: Nitrates converted to nitrites , smoked opiates, fungal toxins in pickled vegetables

Host susceptibility: Esophageal web with glossitis and iron deficiency (Plummer-Vinson or Paterson-Kelly syndrome), congenital hyperkeratosis and pitting of the palms and soles

GERD and its resultant Barrett’s esophagus increase esophageal cancer risk due to the chronic irritation of the mucosal lining. Adenocarcinoma is more common in this condition.

Human papillomavirus (HPV)

Barrett’s esophagus is considered to be a risk factor for esophageal adenocarcinoma

Types Of Esophageal Cancers

Two types of esophageal cancer are squamous cell carcinoma (cancer that begins in flat cells lining the esophagus) and adenocarcinoma (cancer that begins in cells that make and release mucus and other fluids). Adenocarcinomas are often associated with a history of gastroesophageal reflux disease and Barrett’s esophagus. A general rule of thumb is that a cancer in the upper two-thirds is a squamous cell carcinoma and one in the lower one-third is an adenocarcinoma.

There are other rare forms of esophageal cancer including choriocarcinoma, lymphoma, melanoma, sarcoma and small cell cancer.

Clinical Features

Approximately 10 percent of esophageal cancers occur in the upper third of the esophagus, 35 percent in the middle third and 55 percent in the lower third. In the lower third squamous cell carcinomas and adenocarcinomas cannot be distinguished radiologically or endoscopically.

Dysphagia and odynophagia are the most common symptoms of esophageal cancer. Dysphagia is the first symptom in most patients. Odynophagia may also be present. Fluids and soft foods are usually tolerated, while hard or bulky substances (such as bread or meat) cause much more difficulty. Substantial weight loss is characteristic as a result of reduced appetite and poor nutrition and the active cancer. Pain behind the sternum or in the epigastrium, often of a burning, heartburn-like nature, may be severe, present itself almost daily, and is worsened by swallowing any form of food. Another sign may be an unusually husky, raspy, or hoarse sounding cough, a result of the tumor affecting the recurrent laryngeal nerve.

The presence of the tumor may disrupt normal peristalsis leading to nausea and vomiting, regurgitation of food, coughing and an increased risk of aspiration pneumonia. The tumor surface may be fragile and bleed, causing hematemesis. Compression of local structures occurs in advanced disease, leading to such problems as upper airway obstruction and superior vena cava syndrome. Fistulas may develop between the esophagus and the trachea, increasing the pneumonia risk; this condition is usually heralded by cough, fever or aspiration.

Most of the people diagnosed with esophageal cancer have late-stage disease. This is because people usually do not have significant symptoms until half of the inside of the esophagus, called the lumen, is obstructed, by which point the tumor is fairly large.

If the disease has spread elsewhere, this may lead to symptoms related to this: liver metastasis could cause jaundice and ascites, lung metastasis could cause shortness of breath, pleural effusions, etc.

Attempts at endoscopic and cytologic screening for carcinoma in patients with Barrett’s esophagus, while effective as a means of detecting high-grade dysplasia, have not yet been shown to improve the prognosis in the individuals found to have carcinoma. Routine contrast radiographs effectively identify esophageal lesions large enough to cause symptoms

Diagnosis

The diagnosis is best made with esophagogastroduodenoscopy (EGD, endoscopy). Biopsies taken of suspicious lesions are then examined histologically for signs of malignancy.

Additional testing is usually performed to estimate the tumor stage. Computed tomography (CT) of the chest, abdomen and pelvis, can evaluate whether the cancer has spread to adjacent tissues or distant organs (especially liver and lymph nodes). The sensitivity of CT scan is limited by its ability to detect masses (e.g. enlarged lymph nodes or involved organs) generally larger than 1 cm. FDG-PET (positron emission tomography) scan is also being used to estimate whether enlarged masses are metabolically active, indicating faster-growing cells that might be expected in cancer. Esophageal endoscopic ultrasound (EUS) can provide staging information regarding the level of tumor invasion, and possible spread to regional lymph nodes.

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