What is Esophageal Cancer?

  •   Esophageal cancer develops when cancerous cells begin to grow in the lining of the esophagus i.e, a long, hollow tube that connects the throat to the stomach. It allows the swallowed food to move from the back of the throat to the stomach, so that it can be further digested. The inner layer of the esophagus is where the cancer typically first displays itself, and it also tends to spread to other layers of the esophagus and other regions of the body (metastasis) through the lymphatic system (consisting of different types of vessels which specifically drain lymph from the tissues into the blood).

       Men are more prone to esophageal cancer than women. It is ranked as the sixth most common cause of cancer deaths worldwide. Different geographical locations lead to variation in the incidence rates of the disease. Increase in number of cases in certain regions may be due to tobacco and alcohol use or due to particular nutritional habits and obesity.

       Early-stage esophageal cancer can be treated with surgery, as to remove the tumor or relieve the symptoms whereas advanced or later stage esophageal cancer can be treated using chemotherapy, radiation therapy and immunotherapy.

There are two forms of esophageal cancer:

  • Squamous Cell Cancer: A tumor that originates with squamous cells and forms the surface of the skin and lining of hollow organs in the body.
  • Adenocarcinoma: A malignant type of tumor that develops in the areas at the bottom of the esophagus and at the junction where the esophagus joins the stomach as it is lined with columnar cells.

What are the signs and symptoms of Esophageal Cancer?

  •   Early stages of esophageal cancer may not have any apparent symptoms, however advanced stages show the following signs and symptoms:

  • Difficulty or pain when swallowing
  • Unintentional weight loss
  • Coughing
  • Hoarseness
  • Indigestion and heartburn
  • Regurgitation of undigested food
  • Food Sticking in esophagus
  • Vomiting blood or passing old blood with bowel movements

symptoms
causes

What are the main causes of esophageal cancer?

  •   The exact cause of this disease is not known but the factors that contribute in increasing the chance of developing esophageal cancer are:

  • Use of Tobacco:This consists of smoking and the use of smokeless tobacco
  • Alcohol Use:The risk is increased to many folds with heavy alcohol consumption.
  • Obesity:Inflammation caused in obese people by being overweight can lead to the formation of cancer.
  • Barrett's esophagus and chronic acid reflux:Untreated acid reflux can cause changes in the cells at the lower end of the esophagus. People also suffering from long term heartburn are at a greater risk of esophageal cancer.
  • Human Papillomavirus (HPV):HPV is a common virus which is responsible for causing changes in the vocal cords, mouth, hand, feet and genital tissues.
  • Occupational exposure to certain chemicals:Exposure to dry cleaning solvents for a long time increases the risk of developing esophageal cancer.

How is esophageal cancer diagnosed?

  •   The various diagnostic tests for esophageal cancer are:
  • Barium Swallow Study:A liquid containing barium is given to the patient to swallow and then an X- Ray is performed. The esophagus is coated with the barium present in the liquid to show any changes to the tissue on the X-Ray.
  • Endoscopy:A flexible tube connected with a video lens is passed down the throat into the esophagus by your doctor to check for cancer or areas of irritation.
  • Biopsy: (Using a sample of your tissue for testing):An endoscope is passed down your throat into your esophagus to collect a suspicious tissue sample. It is then sent to the laboratory to check the presence of cancer cells.

diagnosis
treatment

What are the available treatment options for esophageal cancer?

  •   The treatment options given to the patient depend entirely on the type of cells involved in cancer, the stage of the cancer and overall health.
  • Surgery:The Surgery can be a preferred for revoking cancer cells, either alone or in combination with other treatments:
    • Removal of very small tumors:If the tumor is within the operatable range and confined to the superficial layer of the esophagus only, then an endoscope can be used to remove the cancer as well as the healthy tissue that surround it to avoid further spreading.
    • To remove a portion of the esophagus (esophagectomy):During esophagectomy, an entire portion of the esophagus that contains cancer is removed along with an upper part of the stomach and nearby lymph nodes. The remaining portion of the esophagus is reconnected back to the stomach.
    • To remove part of your esophagus and an upper part of your stomach:It is also called as esophagogastrostomy, where a part of your esophagus along with a larger part of the stomach and nearby lymph nodes are removed. The remaining part of the stomach is reattached to your esophagus. A part of your colon can be used to join the two.
      Esophageal cancer surgery is a risky procedure, which carries risk of serious complications, like infection, bleeding and leakage from the area where the remaining esophagus is reattached to the stomach.
  • Chemotherapy:Chemotherapy helps in killing of the cancer cells or stops their growth.
  • Endoscopic sub mucosal dissection (ESD):To treat very early-stage esophageal cancer.
  • Endoscopic mucosal resection (EMR):The cancer in the mucous lining is removed using this procedure.
  • Endoscopic Laser Therapy:The tumors in the esophagus can sometimes get obstructive, hence making it hard to swallow. With the help of this treatment, the symptoms can be maintained easily.
  • Photodynamic Therapy (PDT):Photosensitizers are the drugs that destroy the tumor. The killing of cancer cells is done when light activates these drugs, thus creating a chemical reaction.
  • Immunotherapy:Immune checkpoint inhibitors are used in this treatment. The response to the esophageal cancer cells is restored with the help of these drugs.
  • Targeted Therapy:Certain esophageal cancer cells carry an extra quantity of HER2 protein. It is essential for the growth of cancer cells. Therefore, the drugs targeting HER2 proteins are used in the targeted therapy.