Research & Publications > Jefferson Physicians Use Endoscopic Ultrasound to Better Evaluate Gastrointestinal and Rectal Cancers
Jefferson Physicians Use Endoscopic Ultrasound to Better Evaluate Gastrointestinal and Rectal Cancers
Gastroenterologists and radiologists are combining two sophisticated technologies–ultrasound and endoscopy–to improve cancer staging for gastrointestinal (GI) and rectal cancers.
Endoscopic ultrasound (EUS) was developed in the late 1980s, borne out of the difficulty to image hard-to-reach organs and those obscured by intestinal gas, says Anthony Infantalino, MD, Clinical Assistant Professor of Medicine at Jefferson Medical College of Thomas Jefferson University, and Director of Endoscopic Ultrasound at Thomas Jefferson University Hospital.
In endoscopy, a flexible lighted tube is passed into the gastrointestinal tract through the mouth or anus to see the inside lining of digestive organs, including the esophagus, stomach, pancreas, small intestines, colon and rectum.
Ultrasound uses sound waves to make cross-sectional pictures of internal organs. It's usually performed by placing ultrasound probes against the skin. But some digestive organs are deep within the body and difficult for standard ultrasound to reach.
Endoscopic ultrasound combines both technologies, helping to overcome the latter problem. A sensitive ultrasound probe is placed on the tip of an endoscope. Passing the ultrasound endoscope into the gastrointestinal tract places the probe close to many internal organs.
With EUS, says Dr. Infantolino, “You're essentially doing ultrasound from the inside out, imaging all of the major structures and blood vessels that were partially inaccessible before.”
The patient had dysphagia and was diagnosed with esophageal cancer. Subsequently, an endoscopic ultrasound was performed. The fourth layer that corresponds to the muscularis propria has been penetrated by tumor and is invading the periesophageal space. This would correspond to a T3 cancer. This patient would benefit from preoperative chemotherapy and radiation therapy. |
Improved Staging
A major problem in treating patients with GI cancer, he explains, is nonsurgically diagnosing and staging diseases of the digestive tract and nearby areas. “We need to decide which patients should get preoperative chemotherapy, and whose cancer is too far advanced for surgery.”
A combination of clinical exams, blood tests and CT scans, he says, may only accurately stage about 50 to 60 percent of some cancers, such as esophageal. “By adding EUS, we can improve that preoperative staging accuracy to 85 to 90 percent.” He notes that “combining technologies furthers what either by itself can do. By operating only on the patients who will benefit, we save costs. For those with advanced disease, we avoid operating needlessly, and therefore avoid unecessary pain and suffering.
“If cancer researchers are going to study new treatments, the only way to know if they are effective is to have accurate preoperative staging. Without it, you may not be able to tell if the tumor was too far advanced to even attempt a treatment.”
“Endoscopic ultrasound promises to greatly increase our ability to diagnose and thereby effectively treat our patients who have cancer,” says Anthony J. DiMarino Jr., MD, Director of the Division of Gastroenterology and Hepatology in the Department of Medicine and Professor of Medicine at Jefferson Medical College.
EUS also allows physicians to do “real-time biopsies” of digestive organs such as the pancreas. “We're able to pass a needle through the endoscope to simultaneously sample tissue, and using ultrasound, stage the disease,” he explains.
Criteria
Any patient with various GI and GI-related malignancies who has a negative CT scan for distant, untreatable disease, such as that which has spread to the liver. For any cancer that is potentially resectable, the patient should have an endoscopic ultrasound to help further stage the tumor.
To refer a patient or for more information, contact Dr. Anthony Infantolino at 955-8900 or 1-800-JEFF-NOW. |
Less Invasive Treatments
In many cases, EUS eliminates that need for more invasive procedures. For patients with non-small cell lung carcinoma, for example, sampling lymph nodes previously required an operation. “Now, with the advent of ultrasound-guided sampling, you can go through the esophagus and into the lymph nodes, eliminating the need for some operations.” There are other uses of the technology. EUS allows specialists to inject pain medications, for example, directly to the appropriate body area, says Dr. Infantolino.
Doctors can also treat tumors using ultrasound-guided fine needle injection therapy. “We can even do radiofrequency therapy using a thin radioablation catheter that can go through an endoscope,” Dr. Infantolino says. “We don't know if it's curative as yet, but it's something we'll be looking at in the future.” Still, interpreting such ultrasounds is not easy. He points out that it normally requires years of experience and a large volume of patients to develop the appropriate expertise and accuracy in reading endoscopic ultrasounds.
According to Dr. Infantolino, Thomas Jefferson University Hospital is one of only three institutions in Pennsylvania currently using PDT.
Patient has an obstructing esophageal cancer. He was infused with Photofrin 36 to 48 hours prior and placed in a dark environment. The cancer cells selectively pick up the photosensitizer. Subsequently, a laser fiber is advanced through the tumor and it is exposed to red light at 630 nm causing tumor ablation. |
Using Light Therapy to Help Patients Swallow Again
Thomas Jefferson University Hospital is opening a new facility for photodynamic therapy (PDT), which uses light to treat some kinds of cancer. PDT isn't new, but only in recent years has it been used in digestive tract disease. It currently is used in treating esophageal cancer and lung cancer, for which it is Food and Drug Administration approved. It's also seen as a “cure” for some cases of early esophageal cancer, says Anthony Infantolino, MD, Clinical Assistant Professor of Medicine at Jefferson Medical College.
PDT takes advantage of the characteristics of a chemical called photofrin, which is injected into the body. When exposed to light at a wavelength of 630 nm, a chemical reaction occurs, and substances called singlet oxygen and hydroxyl radicals are released. “It restores some patients' capability to swallow,” says Dr. Infantolino. “Some data suggest that PDT may be curative in early esophageal cancer.” More data is needed, he says, before such therapy would be offered as a first-line treatment.
“But for patients who are for some reason not surgical candidates–say from underlying heart or lung disease, and who would not likely survive an operation–this could be an effective alternative. We're also looking at treating some pre-cancerous lesions of the esophagus this way.”
Currently, PDT is FDA-approved for advanced esophageal and bronchogenic cancers. Some early stage disease may be treated in this manner as well.
Patients eligible for treatment with PDT include those who have esophageal cancer with difficulty swallowing and who do not respond to traditional therapy, including radiation and Nd:YAG laser treatment. Those with lung cancer and partial airway obstruction are also eligible.
He cautions that a “risk for such patients is severe sunburn if exposed to any bright light, especially in the immediate weeks after the procedure.” Some local swelling and inflammation may occur in and around the esophagus, which may cause chest discomfort. Other potential side effects include nausea, fever, and/or constipation.
Generally, patients have to stay in a dark room prior to the procedure, and up to 30 days after. “Researchers are working on new photosensitizing agents, which will avoid the sunburn complications,” he notes.
Originally Printed: Jefferson Gastroenterology,
Volume 2 Number 2, September 1999
A publication of Thomas Jefferson University Hospital
Editor: Steve Benowitz
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