Esophageal cancer is characterized by the malignant mutation of the cells that line the esophagus. The esophagus is a tube-like passage that links the throat with the stomach, it is the medium through which food passes from the mouth to the stomach. It denotes the swallowing action. It is made up of muscles that contract to push food and liquids down the stomach. The occurrence of cancerous cells in the muscular tissues of the esophagus is known as esophageal cancer. There are two major types of this form of cancer, these are:
- Squamous cell cancer of the esophagus: Its development is associated with the use of tobacco products (with or without smoke) and alcohol.
- Adenocarcinoma: It is cancer that affects the lower part of the esophagus. It is believed to be associated with gastroesophageal reflux disease (GERD), which occurs when stomach acid continuously leaves the stomach and gets into the esophagus. Over time, the accumulation of stomach acid in the esophagus can cause inflammation and cell damage, which can subsequently result in the formation of abnormal cells (metaplasia) and if treatment is not started, the lining of the esophagus will undergo mutative changes and malfunction (dysplasia). Barret’s esophagus (abnormal dysplasia) is another condition that can lead to adenocarcinoma. Smoking also increases the risk of developing adenocarcinoma but alcohol doesn’t.
ESOPHAGEAL CANCER CAUSES AND RISK FACTORS
Esophageal cancer causes and risk factors are things that may predispose one to the condition. It is believed that chronic irritation of the esophagus is one of the possible causes of the disease. Factors that can contribute to esophageal irritation or inflammation which can increase the risk of developing esophageal cancer include:
- Barette’s esophagus (having precancerous cells in the esophagus)
- Alcohol addiction or chronic alcohol drinking
- Achalasia(a condition that causes difficulty with swallowing when the esophageal sphincter is unable to relax).
- Consistently drinking hot and scalding liquids
- Gastroesophageal reflux disease (Disease)
- Bile reflux disease
- Inadequate consumption of fruits and vegetables
- Age (commonly affects people aged 50 and above)
- Gender (It is more prevalent in men than in women)
- Race ( Adenocarcinoma is more prevalent in white men than in other races, while squamous cell esophageal cancer is more prevalent among blacks than whites)
ESOPHAGEAL CANCER SYMPTOMS
Esophageal cancer rarely manifests any symptoms until the tumor has grown large enough(metastasized) to constrict the esophagus and hinder the easy passage of food. The absence of symptoms in the developmental stages of the disease makes the signs of esophageal cancer hard to miss until the disease has progressed to an advanced stage. This is when symptoms begin to manifest. Some of the symptoms of esophageal cancer are:
- Difficulty swallowing (Dysphagia)
- Unexplained weight loss
- Chronic chest pain, heartburn, and indigestion (especially when adenocarcinoma is GERD related)
- Esophageal bleeding ( indicated by black vomit and tarry stools, sometimes bleeding can only be detected by a microscope).
- Fatigue and anemia
WHAT ARE THE WARNING SIGNS OF ESOPHAGEAL CANCER?
Since the symptoms of esophageal cancer are very difficult to spot in the early stages. It is important to note some of the warning signs of esophageal cancer. The first sign or symptom of esophageal cancer is often dysphagia, which is the medical term for swallowing difficulty.
The first indication of dysphagia is usually difficulty in swallowing solid foods, which may later worsen to include liquids. This is why all complaints or issues with swallowing difficulties should not be taken lightly. If cancer has grown to throw the lymph system, abnormal and swollen lymph nodes may be visible around the neck, below the Jaw, and above the collarbones (Clavicle).
HOW IS IT DIAGNOSED?
Esophageal cancer is diagnosed through endoscopy and biopsy. When a patient presents dysphagia, the gastroenterologist normally performs an endoscopy which is a procedure that involves the patient swallowing a flexible tube that has a camera. The doctor is then able to see the patient’s esophagus, stomach, and the upper part of the duodenum. The presence of a mass in the esophagus will necessitate a biopsy (sample of tissue) screening. The gastroenterologist can obtain the biopsy through the same tube.
The tissue biopsy is then examined by a pathologist with the aid of a microscope to confirm either the presence or absence of cancer cells. If the presence of cancerous cells is confirmed, X-rays, PET scans, and CT scans can be used to check for the spread of cancer to other body sites beyond the esophagus.
ESOPHAGEAL CANCER STAGING
Esophageal cancer staging refers to the system of categorizing cancer-based on the length of its metastasis. It describes how far cancer has spread within the esophagus, the lymph system, and other organs of the body. Tests such as bronchoscopy, endoscopic ultrasound (EUS), Computerized tomography (CT), and Positron emission tomography (PET) are used to determine how far cancer has spread from the esophagus. There are four major stages of esophageal cancer :
Stage I (T1 & T2 cancers) : These are early-stage cancers that are present only in a small area of the mucosa (the inner lining of the esophagus that is made up of squamous cells) and have not spread to the submucosa (the connective tissues made up of glands that produce mucus which serves as lubricants for the easy passage of food).
T2 cancers: are cancers that have spread to the esophageal muscular propia which is made up of skeletal and smooth muscle cells that enable powerful peristalsis(muscle contractions).
Stage II: These are cancers that have metastasized into the primary muscle layer of the esophagus or into the connective tissues of the outer part of the esophagus. May also include cancers that have spread into one or two lymph nodes that are close to the esophagus.
Stage III: These are cancers that have penetrated the wall of the esophagus and have spread to the outer layer, as well as cancers that have metastasized into nearby organs and tissues.
Stage IV: This is the terminal stage of esophageal cancer, it refers to cancerous cells that have spread to distant lymph nodes and other organs and tissues that are far from the esophagus.
ESOPHAGEAL CANCER TREATMENT
Treatment for esophageal cancer takes into consideration the type of cancerous cells, the stage of cancer, health history, and the patient’s preference. Below are some modes of treatment for esophageal cancer:
Surgery: This type of treatment is usually recommended for patients with stage I esophageal cancer who are otherwise healthy. It involves the use of surgery to remove the part of the esophagus that has cancer.
It is also used for treating people with cancer complications, such as those suffering from chronic dysphagia due to tumor obstruction in the esophagus. The surgeon, in this case, will use certain tools or an endoscope to place a metal tube (stent) that helps to widen the constricted esophagus.
Chemotherapy: This is the use of special drugs and chemicals to eliminate cancerous cells. Chemotherapy is often used in combination with surgery.
The drugs can be given before or after surgery. In some cases of esophageal cancer, chemotherapy can also be combined with radiation therapy It can also be used as a single treatment to treat people with advanced esophageal cancer that has metastasized beyond the esophagus, where it provides relief for the associated symptoms.
Radiation therapy: This is the use of special machines that emit high energy beams such as x-rays and protons to eliminate cancer cells. The machine can be positioned outside the body (external beam radiation) in such a way that it aims its beams at the targeted cancer cells.
It can also be positioned inside the body (brachytherapy) near the cancer cells, but this method is rarely used. Radiation therapy is often used in combination with chemotherapy before or after esophageal cancer surgery to enhance the effectiveness of treatment.
Targeted drug therapy: This involves the use of special drugs that target deficiencies or weaknesses within the cancer cells. The drugs act by blocking these deficiencies, which results in the death of the cancer cells. Targeted drugs are mostly combined with chemotherapy to treat advanced-stage cancers or cancers that are resistant to other treatments.
Immunotherapy: This involves the use of drugs that trigger immune function. Usually, the immune system is unable to fight cancer cells because the cells produce certain proteins that immune cells do not recognize as pathogenic or dangerous. These drugs interfere with this cancer mechanism. Immunotherapy is usually used to treat advanced or recurrent esophageal cancer.
ESOPHAGEAL CANCER PROGNOSIS
Esophageal cancer is treatable in most cases, but it is hard to cure. The prognosis or survival rate is good for people who are diagnosed which chronic barrette’s esophagus (the development of precancerous cells). Those with few cancer cells have a relatively good prognosis.
The survival rate or prognosis is an estimated percentage of people with a certain type and stage of cancer who survived the disease for a certain period of time (usually 5 years) after diagnosis.
It is important to note that the survival rate isn’t a general yardstick to determine how long each individual will live after diagnosis, but it gives an idea of the success rate of treatments. It may also not predict the outcome of every cancer patient as some cases may differ.
According to the American cancer society, the survival rate for esophageal cancer is a 5-year mark with varying percentages based on the growth and spread of the cancerous cells. The spread, in this case, is not categorized into stages but it is grouped into :
- Localized: The cancer is still within the esophagus
- Regional: Cancerous cells have grown into nearby lymph nodes or tissues
- Distant: Cancerous cells have spread to other organs and lymph nodes that are far from the esophagus.
For localized cancer, the five-year relative survival rate is 47%
For regional cancer, the five-year survival rate is 25%
For distant, the five-year relative survival rate is 5%
This means that there is a better outlook for patients who are still in the early and pre-advanced stages of Esophageal cancer (47% and 25%) than those in advanced stages of cancer such as stage 4 esophageal cancer.
Note that the prognosis is the same for both adenocarcinoma and squamous cell esophageal cancer.
PREVENTION TIPS FOR ESOPHAGEAL CANCER
There is no definite way to prevent the development of esophageal cancer, but identifying some of the risk factors and keeping healthy can reduce your chances of developing the disease. Some of the things you can do to reduce your risk are :
- Cut back on alcohol consumption
- Quit smoking
- Treat all cases of acid reflux, indigestion, or GERD. Consult your doctor if you have persistent heartburn that barely responds to the medication.
- Make exercise a regular habit in order to keep fit and maintain a healthy BMI
- Eat lots of fruits and vegetables
ESOPHAGEAL CANCER Q&A
Q: What is the first sign of esophageal cancer
A: Esophageal cancer is often preceded by swallowing difficulty (Dysphagia)
Q: Is esophageal cancer a death sentence
A: No it isn’t a death sentence, the outlook is good for people with early and pre-advanced stages of the disease. Committing to treatment and keeping a positive attitude will also improve your chances of survival.
Q: What are the signs and symptoms of the last stage of esophageal cancer
A: Chronic dysphagia (a liquid-only diet may be necessary), difficulty breathing, chronic hoarseness that may impair speech, nausea and vomiting, fatigue, anemia(blood loss), hiccups, and esophageal bleeding.
Q: Would a chest Xray show esophageal cancer
A: Yes it can show signs that indicate the presence of cancer
Q: How long do you live after being diagnosed with esophageal cancer
A: The average survival rate (in years) after diagnosis, is 5 years.