Cancer may develop at any point in the digestive system. These include common cancers such as colon and rectal cancers, and less common cancers that occur in the esophagus, pancreas, gallbladder, liver and stomach. Gastroenterologists and hepatologists work in close collaboration with surgeons, radiologists and oncologists to diagnose and treat cancers of the digestive system.
Endoscopy is an important tool for treating early cancers of the digestive tract without surgery. Endoscopy is also used to stage cancers to determine if surgery is a viable treatment option.
Endoscopic cancer treatment is aimed at:
- Curing early stage cancer, limiting the need for other treatments such as radiation, surgery or chemotherapy
- Relieving symptoms in patients with advanced cancer to improve quality of life (palliative care) without surgery.
Endoscopic procedures for treating cancer include:
- Laser therapy uses high-intensity light to destroy cancer cells. Laser endoscopy involves aiming laser beams at cancer through an endoscope. It is used to treat cancer or precancerous growths inside the esophagus, stomach or colon. In patients with esophageal cancer, laser endoscopy can alleviate (palliate) symptoms such as dysphagia (difficulty swallowing) caused by tumors blocking the esophagus as well as bleeding. Froedtert & The Medical College of Wisconsin have the only facility in the state performing laser therapy to treat cancer of the esophagus. Photodynamic therapy is also used to treat esophageal cancer that cannot be treated with laser therapy alone.
- Photodynamic therapy (PDT) uses a light source and a photosensitizing agent (a drug activated by light) to destroy cancer cells in the lining of the esophagus. The procedure involves injecting the agent into the bloodstream. The agent is absorbed by cells all over the body, including the tumor. One to three days later, the agent leaves the normal cells but remains in cancer cells. At this stage, the tumor is exposed to light from a laser light through an endoscope placed into the esophagus. The light causes the agent in the cancer cells to change, and this change kills the cancer cells.
PDT is used to treat patients with Barrett’s esophagus with dysplasia (abnormal growth), a condition that may lead to esophageal cancer. PDT can also cure some very early esophageal cancers that have not spread to deeper tissues. PDT may be performed as a palliative treatment for a patient with advanced cancer of the esophagus to kill enough of the cancer to improve the person’s ability to swallow.
- Cryoablation uses liquid nitrogen sprayed at low pressure through a catheter placed through an endoscope to treat Barrett’s esophagus. The liquid nitrogen destroys cancer cells by freezing them.
- Endoscopic mucosal resection (EMR) is performed to remove early cancer and precancerous lesions of the gastrointestinal tract. The treatment of early gastrointestinal cancers with EMR may prevent the need for surgery in some patients.
Endoscopy allows viewing and access to the mucosa, the innermost lining of the gastrointestinal tract and the site where most gastrointestinal cancers originate. The EMR technique allows a gastroenterologist to obtain tissue and/or remove lesions that cannot be accessed with standard biopsy or surgical removal techniques. EMR can also be used to stage the depth of tumor invasion in the mucosa.
EMR is especially useful in removing slightly elevated, flat or slightly depressed cancerous lesions of the mucosa (such as in the stomach or esophagus), which are difficult to grasp with a traditional wire snare (such as those used to remove colon polyps). EMR elevates the mucosa, allowing the lesion to be grasped with a snare. Through a two-channel endoscope, one tool is used to snare the lesion, while another tool is used to cut it out.
Author: Marla Fraunfelder
|Medical Reviewer: ||Kia Saeian, MD, MSC, EPi, FAGG|
|Medical College of Wisconsin gastroenterologist/hepatologist||