Using EUS to stage esophageal or gastric cancer
Teodor C. Pitea, MD, is a gastroenterologist and therapeutic endoscopist at Banner Del E. Webb Medical Center.
Question: I have a small cancerous tumor in my esophagus and my doctor is ordering an endoscopic ultrasound to evaluate the tumor. Why is this test useful?
Answer: Endoscopic ultrasound (EUS) accurately predicts the stage of esophageal cancer, allowing your doctor to determine a treatment plan. EUS can also be used to assess other gastrointestinal (GI) cancers, including those in the stomach and rectum.
EUS is performed with an endoscope, which is a thin, flexible tube that has a camera, a light source and an ultrasound probe attached to its tip. The ultrasound provides images of the wall of the digestive tract and surrounding organs like the liver or lymph nodes. In your case, the EUS will capture images of the wall of your esophagus, which has four main layers.
If the cancer is located only in the first layer, called the mucosa, it is highly unlikely it has spread further. In that case, your tumor can actually be removed without surgery using endoscopic mucosal resection, or EMR. The EMR can be performed at the time of EUS to minimize the need for multiple procedures. Both are outpatient procedures that require no special preparation other than an empty stomach.
If the tumor is found in the deeper layers of the esophageal wall, EMR is not a treatment option. The EUS images will identify suspicious lymph nodes and evaluate additional lesions to determine if the cancer has spread to other organs along the digestive tract. Once the cancer stage is determined, your doctor will recommend a treatment plan, including possible surgery.
Not only is EUS very useful in determining the stage of most GI cancers, the combination of EUS and EMR is the recommended minimally invasive approach for removing small tumors in the digestive tract. EMR of early cancer is particularly helpful for individuals whose age or other health conditions could make surgery risky or complicated.