PDA

View Full Version : Cryotherapy for Esophageal Diseases


daw
05-13-2005, 10:31 AM
Navy Doctor Pioneers Esophagus Treatment Technique
By Rudi Williams, American Forces Press Service

Reprinted from: Navy and Marine Corps Medical News, Issue 10, April 29, 2005.

BETHESDA, Md., – A Navy doctor at the National Naval Medical Center in Bethesda, Md., has found a way to eliminate pain and suffering and save the lives of patients with Barrett’s esophagus and other deadly esophageal diseases without performing the major surgery that has been the normal recourse.

CAPT Mark Johnston is making medical history with his innovative use of “cryotherapy,” the application of extreme cold, for the treatment of serious esophageal diseases.

Johnston said the freezing technique has been used for decades in treating certain cancers in various medical specialties such as dermatology, gynecology and urology.

But this marks the first time the technique, which dates back to the 1850s, is being used in the field of gastroenterology for esophageal mucosal ablation and other diseases, he said.

Johnston holds many credentials. He's chief of gastroenterology and director of the Colon Cancer Center at Bethesda. He’s also an associate professor of medicine at the Uniformed Services University of Health Sciences and a gastroenterology consultant to the U.S. Congress, Supreme Court and White House.

Johnston said Barrett’s is a condition in which the esophagus, the muscular tube that carries food and saliva from the mouth to the stomach, changes so that some of its lining is replaced by tissue similar to that normally found in the intestine.

“Once you get that kind of cell, your risk for getting cancer in the esophagus can go up over a hundredfold,” he noted.

Barrett’s esophagus can lead to a form of esophageal cancer known as adenocarcinoma. Over the last 25 years, the incidence of this cancer has increased faster than any other malignancy in the Western world, Johnston noted.

“Normally when acid comes up, burns and damages, the lining of the esophagus, it will heal back with the normal tissue,” Johnston said. “In some people, it heals back with abnormal tissue, which is what we call Barrett’s esophagus. It’s that tissue that’s at risk for turning into cancer.”

It’s still in the testing, research and development stage, but Johnston’s freezing technique replaces surgery with an outpatient procedure that takes only 15 to 20 minutes, and it’s pain-free, he noted.

“When it’s over, the patient can get up and walk down to the coffee shop and have a cup of coffee, or a hamburger -- no problem,” Johnston said. “So we went from an esophagectomy that results in being in the hospital from seven to 21 days, to walking in, getting your procedure done and walking out in time to have lunch.”

The doctor has successfully treated more than 25 patients, including two with high-grade dysplasia, a close precursor to cancer, which normally would have been treated with an esophagectomy, he said. “We’ve reversed Barrett’s in every single one of them,” he added. “We’ve had no complications – zero – in a first-of-its-kind study.”

“We’ve also treated one patient off-protocol with FDA permission who had esophageal cancer. He is now 10 months out from treatment and cancer free.” Johnston said.

Johnston started thinking about a gentler and less invasive method of treating esophageal disease while reviewing research at the annual American College of Gastroenterology meeting in 1994. “Multiple papers had demonstrated the efficacy of ablating Barrett’s esophagus using various techniques such photodynamic therapy, laser, and argon plasma coagulation to name a few; yet, all these techniques were associated with either high cost, technical difficulties or lack of complete efficacy. I thought, 'Why not freeze the esophagus?'” Johnston said.

“Gynecologists have been freezing dysplasia, early cancer in the cervix, just by spraying it. Why not just spray the lining of the esophagus,” he said.

When he returned to his office, he absorbed himself in a big Internet literature search. “I found out that spraying and freezing the lining of the esophagus had never been done before – not a single abstract, no report, nowhere in the world in medical literature,” Johnston. “So it was a new idea.”

After talking it over with his mentor, Andre Dubois, a research professor at the university, Johnston went home and built a prototype device in his garage.

After becoming a staff doctor at the Bethesda naval hospital in 1995, Johnston found out that the
university had a $12,000 starter grant earmarked for young investigators to encourage development with new ideas and to get them involved in research. He managed to obtain some money for his research.

The Navy doctor’s quick, painless technique could be a godsend for people around the world. Approximately, 10-14% of people in the United States experience acid reflux disease. As many as 10-20% of them will develop Barrett’s esophagus with its inherent risk of developing esophageal cancer, Johnston said. Barrett’s esophagus, which may cause no symptoms itself, is estimated to affect about 3-10 million adults in the United States alone.

http://www.bethesda.med.navy.mil/Patient/Health_Care/Surgery_Services/Gastroenterology/Cryotherapy.aspx

daw
05-14-2005, 03:29 PM
BIOMEC CLOSES DEVELOPMENT AND MANUFACTURING DEAL WITH CRYMED TECHNOLOGIES INC.

Cleveland, Ohio (April 19, 2005) – Trevor O. Jones, Chairman and CEO, announced that BIOMEC has been selected by CryMed Technologies, Inc. to design, develop and manufacture its cryogenic system to treat gastroesophageal disorders including Barrett’s Esophagus.

In 1996 CryMed Technologies, in conjunction with Dr. Mark H. Johnston (current Chief of Gatstroenterology at The National Naval Medical Center in Bethesda, MD), initiated the development of a novel medical device aimed at utilizing and delivering a cryogen (liquid nitrogen) to ablate Barrett’s Esophageal cells. As a result of this development the United States Patent and Trademark Office issued CryMed two patents. Additionally, in May 2004, the Food and Drug Administration issued CryMed a 510(k) approval authorizing the company to market its device.

The device under commercial development at BIOMEC is a patented catheter and delivery system that enables a physician to regulate, transport, and spray liquid nitrogen under low pressure via the accessory channel of a standard or therapeutic gastrointestinal (GI) endoscope. The initial planned application for the device is the cryoablation of epithelial cells in patients with Barrett’s Esophagus, a fairly common ailment sited as the precursor to esophageal cancer. There is currently no known cure for Barrett’s Esophagus, although competing therapeutic technologies do exist. It is anticipated that the device eventually will be used for cryoablating tissue lesions related to other maladies in the upper and lower gastrointestinal tract.

To date, Dr. Johnston has successfully used CryMed’s device to treat 28 patients with Barrett’s at the National Naval Medical Center with no recurrence of the ailment after as many as eighteen months from the initial treatment.

CryMed recently completed a successful $3.7 million equity offering in which BIOMEC was the lead investor.

BIOMEC Inc. is a Cleveland headquartered biomedical device company established in 1998 with the specific objective of accelerating promising technology from major medical and academic institutions, national laboratories, and from internal proprietary developments to successful commercial products.

http://www.biomec.com/news/news_release.asp?id=37