The tube that attaches the throat to the stomach is known as the esophagus. This 10-inch long muscular tube is a part of the digestive tract from where the food travels from the esophagus to the stomach.
The esophagus is comprised of four layers that include –
- Outer Layer: The esophagus is covered by this outer layer.
- Inner Layer or Lining: This layer helps in passing the food to the stomach as this layer is properly moist.
- Muscle Layer: This layer helps in pushing down the food to the stomach.
- Submucosa: Mucus is made by the glands present in this layer. This mucus moisturizes the esophagus.
What is Esophageal Cancer?
The uncontrollable growth of cancer cells in the esophagus causes esophageal cancer. This cancer begins at the inner layer of the esophagus that can spread further to the other layers of the esophagus and also to different body parts
Esophageal cancer has been categorized into two types that include –
- Adenocarcinoma: This type of esophageal cancer starts in the glandular tissue in the lower part of the esophagus. The stomach and the esophagus appear together in this lower part of esophagus.
- Squamous Cell Carcinoma: Squamous cell carcinoma begins in the squamous cells lining the esophagus. This type of esophageal cancer typically occurs in the middle and upper part of the esophagus.
Causes and symptoms:
There are known causes of esophageal cancer that happens when the cells in esophagus develop errors in their DNA. These cells grow and divide abnormally due to these errors. These abnormal cells eventually form a tumor in the esophagus that spreads to surrounding structures including different body parts.
- Hoarseness or coughing
- Difficulty in swallowing
- Heartburn or indigestion
- Unexplained weight loss
- Frequent choking while eating
- Chest burning, pain or pressure
The first step in evaluating esophageal cancer is usually an endoscopic examination of the esophagus (esophagoscopy). During this procedure, oncologist guides a thin, lighted tube called an endoscope down the esophagus and into your stomach. The endoscope provides a clear view of the esophagus and allows the oncologist to remove a small sample of tissue (biopsy), which is sent to a pathologist for further study.
In some cases, patient may have a barium X-ray, a test in which a chalky liquid (barium) is used to coat the lining of the esophagus so that the lining shows up clearly on a series of X-rays.
If the patient are diagnosed with esophageal cancer, he will need further tests to determine how deeply the cancer has penetrated into the layers of the esophagus and whether it has spread to the lymph nodes or other organs - a process called staging.
Minimally invasive diagnostic techniques are used to stage esophageal cancer. Precisely identifying the extent and spread of the disease is a crucial step in selecting the appropriate treatment for each patient.
Staging tests used include:
- CT scans: The first step in staging esophageal cancer is usually a CT scan, a type of X-ray that produces images of the body in cross sections rather than in the overlapping images produced by conventional X-rays.
- Positron Emission Tomography (PET) scan: This test uses a small amount of radioactive glucose to identify rapidly growing cancer cells and detect changes that aren't visible by other methods.
- Endoscopic ultrasound (EUS): During endoscopic ultrasound, a tiny ultrasound probe is placed into the esophagus through an endoscope. The probe produces sound waves that penetrate deep into tissue, detecting how far a tumor may have spread into the esophagus wall. EUS can be technically demanding, and produces the best results when performed by an experienced endoscopist.
Treatment for Esophageal Cancer in India:
All patients start their treatment only after they have been discussed in the Tumor Board. In the tumor board specialists comprising Medical Oncologists, Radiation Oncologists, Surgical Oncologists, Oncopathologists, Radiologists and Microbiologists evaluate and discuss the findings, and chart out the optimal plan of treatment for each patient based on established national and international guidelines and protocols. This treatment plan takes into account the overall health of the patient, the extent (stage) of the cancer and their preferences. The primary treatments for gastric cancer (stomach cancer) include surgery, radiation therapy and chemotherapy.
Treatment options for esophageal cancer, include surgery, external beam radiation therapy, Brachytherapy, chemotherapy and targeted therapy.
Tremendous advances have occurred in esophageal cancer treatment over the past decade. The include:-
Early esophageal cancer is often treated with endoscopic therapies rather than with surgery. This technique preserves the esophagus, causes minimal trauma and has a low risk of complications. Most people need a minimum of three endoscopic treatments, spaced eight to twelve weeks apart, to remove abnormal cells and allow healthy, new cells to grow in their place.
Specialists offer advanced endoscopic treatments, precisely tailor them to meet the needs of each patient. These therapies include:
- Endoscopic mucosal resection: During EMR, a saline solution is injected under a nodule or lesion in the esophagus. The solution forms a blister that allows oncologists to cut or suction away the lesion, while leaving the rest of the esophagus intact. Patients who undergo this procedure have the same outcomes as people who undergo surgery to remove the entire esophagus.
- Radiofrequency ablation (RFA): In this outpatient procedure, controlled bursts of radiofrequency energy burn away thin layers of abnormal tissue on the surface of the esophagus, leaving healthy tissue intact. Radiofrequency ablation takes about 45 minutes, and patients can usually return to their normal activities the next day, though some patient may experience chest pain and difficulty swallowing for about a week.
- Photodynamic Therapy (PDT): Photodynamic therapy uses a light-sensitive drug and laser light to destroy cancer cells in the esophagus. At the start of treatment, patient were given an intravenous drug called porfimer sodium that makes cancer cells sensitive to light. A few days later, oncologist activates the drug inside the patient's esophagus with a laser light inserted through an endoscope. The laser destroys the targeted cells without harming healthy ones. Photodynamic therapy may also be used to treat cancer that recurs after surgery, radiation or chemotherapy or in conjunction with endoscopic mucosal resection. PDT produces the deepest tissue destruction of any ablative method, but also carries a higher risk of complications.
When cancer is more advanced, surgery to remove the esophagus (esophagectomy) is usually necessary. During the procedure, surgical oncologist remove the damaged portion of the esophagus and sometimes nearby lymph nodes and the upper part of the stomach (fundus).
To re-establish the continuity of the digestive tract, the stomach is formed into a tube and pulled upward to join the remaining portion of the esophagus. Transhiatal esophagectomy, which is performed through the neck and abdomen and is usually effective for cancer higher in the esophagus, and transthoracic esophagectomy, which uses incisions in the abdomen and chest are the types of Surgeries done.
When possible, surgical oncologists perform esophageal surgery using laparoscopic techniques. Unlike traditional open surgery, which requires long abdominal and chest or neck incisions, minimally invasive esophagectomy uses four or five small incisions that require just a stitch or two to close. This approach causes less trauma to the body, and usually leads to shorter hospital stays, reduced postoperative pain and a faster recovery. Minimally invasive esophagectomy is a complex surgery, but it can produce excellent results in the hands of a skilled surgical oncologist.
Depending on the extent of the cancer, surgical oncologists may recommend radiation combined with chemotherapy (chemoradiation) before or after surgery. For patients with more advanced disease, chemotherapy and radiation may be the primary treatment.
When cancer is so widespread that treatment options are limited, palliative care is offered to ease symptoms and improve quality of life. In every case, an experienced, integrated team of care providers serves the social, psychological and spiritual needs of patients and their families.
The team may include physicians from a number of fields as well as dietitians, medical social workers, psychologists, pharmacists and pain management specialists.