Definition of Esophageal Cancer
Esophageal cancer (or oesophageal cancer) is malignancy of the esophagus-a long, hollow tube that runs from the throat to the stomach. There are various subtypes, primarily squamous cell cancer and adenocarcinoma. Squamous cell cancer arises from the cells that line the upper part of the esophagus. Adenocarcinoma arises from glandular cells that are present at the junction of the esophagus and stomach.
Esophageal cancers are typically carcinomas which arise from the epithelium, or surface lining, of the esophagus. Most esophageal cancers fall into one of two classes: squamous cell carcinomas, which are similar to head and neck cancer in their appearance and association with tobacco and alcohol consumption, and adenocarcinomas, which 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. Rare histologic types of esophageal cancer are different variants of the squamous cell carcinoma, and non-epithelial tumors, such as leiomyosarcoma, malignant melanoma, rhabdomyosarcoma, lymphoma and others.
Cause of Esophageal Cancer
It’s not clear what causes esophageal cancer. These risk factors can be cause of the esophageal cancer:
- Age: Age 65 or older is the main risk factor for esophageal cancer. The chance of getting this disease goes up as you get older.
- Gender: Men are more than three times as likely as women to develop esophageal cancer.
- Smoking: People who smoke are more likely than people who don’t smoke to develop esophageal cancer.
- Alcohol: People who have more than 3 alcoholic drinks each day are more likely than people who don’t drink to develop squamous cell carcinoma of the esophagus. Heavy drinkers who smoke are at a much higher risk than heavy drinkers who don’t smoke. In other words, these two factors act together to increase the risk even more.
- Diet: Having a diet that’s low in fruits and vegetables may increase the risk of esophageal cancer. However, results from diet studies don’t always agree, and more research is needed to better understand how diet affects the risk of developing esophageal cancer.
- Obesity: Being obese increases the risk of adenocarcinoma of the esophagus.
- Acid reflux: Acid reflux is the abnormal backward flow of stomach acid into the esophagus. Reflux is very common. A symptom of reflux is heartburn, but some people don’t have symptoms. The stomach acid can damage the tissue of the esophagus. After many years of reflux, this tissue damage may lead to adenocarcinoma of the esophagus in some people.
- Barrett esophagus: Acid reflux may damage the esophagus and over time cause a condition known as Barrett esophagus. The cells in the lower part of the esophagus are abnormal. Most people who have Barrett esophagus don’t know it. The presence of Barrett esophagus increases the risk of adenocarcinoma of the esophagus. It’s a greater risk factor than acid reflux alone. Many other possible risk factors (such as smokeless tobacco) have been studied. Researchers continue to study these possible risk factors.
Having a risk factor doesn’t mean that a person will develop cancer of the esophagus. Most people who have risk factors never develop esophageal cancer.
Signs and Symptoms of Esophageal Cancer
Dysphagia (difficulty swallowing) and odynophagia (painful swallowing) 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, 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 (the organized swallowing reflex), 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 (vomiting up blood). 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, 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.
Risk Factors for Esophageal Cancer
There are a number of risk factors for esophageal cancer. Some subtypes of cancer are linked to particular risk factors:
- Age – most patients are over 60, and the median in US patients is 67.
- Sex – the disease is more common in men.
- Heredity – it is more likely in people who have close relatives with cancer.
- Tobacco smoking and heavy alcohol use increase the risk, and together appear to increase the risk more than either individually. Tobacco and alcohol account for approximately 90% of all esophageal squamous cell carcinomas. Tobacco smoking is also linked to esophageal adenocarcinoma though no scientific evidence has been found between alcohol and esophageal adenocarcinoma.
- Gastroesophageal reflux disease (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. A consequence of GERD is increased exposure of the esophagus to bile acids; and bile acids have been implicated as causal agents in esophageal adenocarcinoma.
- Human papillomavirus (HPV)
- Corrosive injury to the esophagus by swallowing strong alkalines (lye) or acids
- Particular dietary substances, such as nitrosamines
- A medical history of other head and neck cancers increases the chance of developing a second cancer in the head and neck area, including esophageal cancer.
- Plummer–Vinson syndrome (anemia and esophageal webbing)
- Tylosis and Howel–Evans syndrome (hereditary thickening of the skin of the palms and soles)
- Radiation therapy for other conditions in the mediastinum
- Coeliac disease predisposes towards squamous cell carcinoma.
- Obesity increases the risk of adenocarcinoma fourfold. It is suspected that increased risk of reflux may be behind this association.
- Thermal injury as a result of drinking hot beverages
- Alcohol consumption in individuals predisposed to alcohol flush reaction
Diagnosis of Esophageal Cancer
Tests and procedures used to diagnose esophageal cancer include:
Endoscopy. Using the endoscope enables doctor to examines esophagus looking for cancer or areas of irritation.
X-rays of the esophagus. Sometimes called a barium swallow, an upper gastrointestinal series or an esophagram, this series of X-rays is used to examine the esophagus.
Biopsy. A special scope passed down the throat into the esophagus (endoscope) or down the windpipe and into the lungs (bronchoscope) can be used to collect a sample of suspicious tissue (biopsy).
Esophageal cancer staging
After diagnosis, the extent (stage) of the cancer is determined. One of the treatment options is chosen according to the cancer’s stage. Tests used in staging esophageal cancer include computerized tomography (CT) and positron emission tomography (PET).
The stages of esophageal cancer are:
- Stage I. This cancer occurs only in the top layer of cells lining the patient’s esophagus.
- Stage II. The cancer has invaded deeper layers of the patient’s esophagus lining and may have spread to nearby lymph nodes.
- Stage III. The cancer has spread to the deepest layers of the wall of the patient’s esophagus and to nearby tissues or lymph nodes.
- Stage IV. The cancer has spread to other parts of the body.
Prevention from Esophageal Cancer
These steps is to reduce the risk of esophageal cancer. For instance:
- Quit smoking or chewing tobacco. If you smoke or use chewing tobacco, talk to your doctor about strategies for quitting. Medications and counseling are available to help you quit. If you don’t use tobacco, don’t start.
- Drink alcohol in moderation, if at all. If you drink, limit yourself to no more than one drink daily if you’re a woman or two drinks daily if you’re a man.
- Eat more fruits and vegetables. Add a variety of colorful fruits and vegetables to your diet.
- Maintain a healthy weight. If you are overweight or obese, talk to your doctor about strategies to help you lose weight. Aim for a slow and steady weight loss of 1 or 2 pounds a week.
Treatment of Esophageal Cancer
The treatment is determined by the cellular type of cancer (adenocarcinoma or squamous cell carcinoma vs other types), the stage of the disease, the general condition of the patient and other diseases present. On the whole, adequate nutrition needs to be assured, and adequate dental care is vital.
If the patient cannot swallow at all, an esophageal stent may be inserted to keep the esophagus patent; stents may also assist in occluding fistulas. A nasogastric tube may be necessary to continue feeding while treatment for the tumor is given, and some patients require a gastrostomy (feeding hole in the skin that gives direct access to the stomach). The latter two are especially important if the patient tends to aspirate food or saliva into the airways, predisposing for aspiration pneumonia.
Surgery to remove the cancer can be used alone or in combination with other treatments. Operations used to treat esophageal cancer include:
- Surgery to remove very small tumors. If your cancer is very small, confined to the superficial layers of your esophagus and hasn’t spread, your surgeon may recommend removing the cancer and margin of healthy tissue that surrounds it. Surgery for very early-stage cancers can be done using an endoscope passed down your throat and into your esophagus.
- Surgery to remove a portion of the esophagus (esophagectomy). Your surgeon removes the portion of your esophagus that contains the tumor and nearby lymph nodes. The remaining esophagus is reconnected to your stomach. Usually this is done by pulling the stomach up to meet the remaining esophagus. In some situations, a portion of the colon is used to replace the missing section of esophagus.
- Surgery to remove part of your esophagus and the upper portion of your stomach (esophagogastrectomy). Your surgeon removes part of your esophagus, nearby lymph nodes and the upper part of your stomach. The remainder of your stomach is then pulled up and reattached to your esophagus. If necessary, part of your colon is used to help join the two.
Esophageal cancer surgery carries a risk of serious complications, such as infection, bleeding and leakage from the area where the remaining esophagus is reattached. Surgery to remove your esophagus can be performed as an open procedure using large incisions or with special surgical tools inserted through several small incisions in your skin (laparoscopically). How your surgery is performed depends on your situation and your surgeon’s experience and preferences.
Surgery for supportive care
Besides treating the disease, surgery can help relieve symptoms or allow you to eat.
- Relieving esophageal obstruction. A number of treatments are available to relieve esophageal obstruction. One option includes using an endoscope and special tools to widen the esophagus and place a metal tube (stent) to hold the esophagus open. Other options include surgery, radiation therapy, chemotherapy, laser therapy and photodynamic therapy.
- Providing nutrition. A surgeon inserts a feeding tube (percutaneous gastronomy) so you can receive nutrition directly into your stomach or intestine. This is usually temporary until the surgical site heals or until you’re finished with chemotherapy and radiation therapy.
Chemotherapy depends on the tumor type, but tends to be cisplatin-based (or carboplatin or oxaliplatin) every three weeks with fluorouracil (5-FU) either continuously or every three weeks. In more recent studies, addition of epirubicin was better than other comparable regimens in advanced nonresectable cancer. Chemotherapy may be given after surgery (adjuvant, i.e. to reduce risk of recurrence), before surgery (neoadjuvant) or if surgery is not possible; in this case, cisplatin and 5-FU are used. Ongoing trials compare various combinations of chemotherapy; the phase II/III REAL-2 trial – for example – compares four regimens containing epirubicin and either cisplatin or oxaliplatin, and either continuously infused fluorouracil or capecitabine.
Radiation therapy uses high-powered energy beams to kill cancer cells. Radiation can come from a machine outside your body that aims the beams at your cancer (external beam radiation). Or radiation can be placed inside your body near the cancer (brachytherapy).
Radiation therapy is most often combined with chemotherapy in people with esophageal cancer. It can be used before or after surgery. Radiation therapy is also used to relieve complications of advanced esophageal cancer, such as when a tumor grows large enough to stop food from passing to your stomach.
Side effects of radiation to the esophagus include sunburn-like skin reactions, painful or difficult swallowing, and accidental damage to nearby organs, such as the lungs and heart.
Combined chemotherapy and radiation
Combining chemotherapy and radiation therapy may enhance the effectiveness of each treatment. Combined chemotherapy and radiation may be the only treatment you receive, or combined therapy can be used before surgery. But combining chemotherapy and radiation treatments increases the likelihood and severity of side effects.