Most esophageal cancer begins in the epithelium or surface lining of the esophagus and can occur anywhere in the esophagus. Since the esophageal mucosa is richly supplied with lymphatic terminals, there is an early spread of tumors in the lymph nodes. This increases the aggressiveness of the cancer. It is often present in the mid or lower portion of the esophagus.
Esophageal cancer is more prevalent in Asia and parts of Africa, and in the United States where African-Americans have a higher incidence of esophageal cancer relative to whites. In the list of cancers that cause most deaths worldwide, esophageal cancer is one of the top ten.
There are two main types of esophageal cancer: squamous cell carcinoma and adenocarcinomas. The former is a cancer of thin cells that cover the surface of the esophagus and occurs most frequently in the esophagus mid-section. Squamous cell carcinoma is related with smoking and alcohol consumption, and is the type of esophageal cancer with higher incidence in the world. Adenocarcinomas start in mucus-secreting glands and frequently occur in the lower portion of the esophagus. They are often associated with conditions such as gastroesophageal reflux disease (GERD) and Barrett's esophagus and are the most common form of esophageal cancer in the United States. Other, rare types of esophageal cancer include small cell cancer, lymphoma, sarcoma choriocarcinoma, and melanoma.
There are several factors that contribute in the development of esophageal cancer.
- Alcohol intake
- Chronic irritation of the mucosal lining due to long-term GERD
- Barrett's esophagus
- Gender - it is more frequent in men than in women
- Genetic factors
- Foods with high levels of nitrosamine (pickled and fermented foods)
- Swallowing strong alkaline or acids
- Human papillomavirus infection
- Difficulty in swallowing due to the inability of the sphincter to relax (achalasia)
Symptoms of esophageal cancer include:
- Difficulty swallowing (Dysphagia)
- Painful swallowing (odynophagia)
- Weight loss
- Chest pain
- Persisting cough
- Indigestion and heartburn
- Nausea and vomiting
Cancer of the esophagus is often asymptomatic in its early stages. By the time a tumor causes symptoms, it has already spread quite significantly.
Tests for esophageal cancer may include:
Chest X-ray and barium swallow constitutes the primary diagnostic test for dysphagia. The patient will ingest a liquid that will help to outline the esophagus and become visible to the X-ray.
Endoscopy uses a thin tube with a light and a camera at one end (endoscope). The endoscope is placed down the throat into the esophagus in order to check for any abnormalities. The doctor performing the endoscopy may take samples for biopsy of any suspicious tissue. The endoscopy may be performed up to the stomach and duodenum. This is called an esophagogastroduodenoscopy, and provides the most direct assessment of esophageal cancer. Bronchoscopy is a type of endoscopy using an endoscope designed to examine the trachea and lungs.
Laryngoscopy to inspect the larynx with an endoscope.
Computed tomography (CT) scan, positron emission tomography (PET) or Endoscopic ultrasound are imaging techniques that help in identification of metastasis that might be present in the chest or abdomen. The information from these assessments is used in determining the stage of the tumor.
Surgery is the primary treatment for esophageal cancer. The main goal is the removal of the cancer, however, complete resection might not be possible and in certain cases surgery might not be possible.
In the early stage of cancers with small tumors, Endoscopic Therapy for Localized Disease could be performed safely and effectively. Electrocoagulation, laser surgery or photodynamic therapy may be used in this setting to kill cancer cells.
In more advanced cases, resection of part of the esophagus (esophagectomy) or part of the esophagus and upper stomach (esophagogastrectomy) might be performed depending on the extent of tumor spread.
Radiation therapy kills cancer cells with radiation and is often combined with chemotherapy. It can be used either before or after surgery. Radiation given alone can provide palliation of symptoms by shrinking the tumor.
Chemotherapy uses drugs or chemicals to kill cancer cells and is often combined with radiation.
Flexible stents are mostly used for palliative purposes to prevent the cancerous growth to occupy the center of the esophageal tube and consequent obstruction of the esophagus.
Esophageal cancer is a serious and difficult disease to cure, since during the early stage of cancer, it barely manifests a symptom. When the cancer is detected at an early stage, surgery or other therapy may be performed and the chance of survival is high.
However, for people whose cancer has already metastasized and spread to nearby organs, their chance of survival decreases and a cure is no longer possible. The only treatment available is relieving the symptoms (palliation).
To help prevent esophageal cancer, individuals should maintain a healthy diet and lifestyle, without smoking and excessive drinking.
Living with esophageal cancer is difficult and can be devastating. Keep informed about esophageal cancer and new treatments for this condition. Join support groups to share experiences and you will be able to learn from others with this experience who may help you to cope with your condition. Maintain a healthy diet and lifestyle as this will help to fight the cancer.
There are several clinical trials evaluating new cancer treatments for different types of esophageal cancer. Epidemiological and biological studies attempt to clarify the factors associated with development of esophageal cancer.