The rapidly climbing obesity rates in the United States have created a higher risk of esophageal cancer linked to reflux disease. And this has some surgeons wondering if a currently popular procedure to remove the esophagus is as safe in obese patients.
According to a new study at the University of Michigan Health System, obese patients who underwent a procedure called transhiatal esophagectomy primarily for esophageal cancer had outcomes similar to their lean counterparts.
"The type of patient who currently develops esophageal cancer has changed dramatically in the last 20 years. Esophageal cancer used to be primarily squamous cell carcinoma found in people who drank alcohol and smoked excessively. In association with the horrendous epidemic of obesity in this country, we have seen a 350 percent increase of adenocarcinoma over the last 30 years.
This is related to more gastroesophageal relux and Barrett's esophagus in these patients," says Mark Orringer, M.D., John Alexander Distinguished Professor of Surgery at the U-M Medical School.
Orringer and lead study author Christopher Scipione, a U-M medical student, will present the study results Tuesday, Jan. 30, at the Society of Thoracic Surgeons 43rd annual meeting in San Diego.
Adenocarcinoma of the esophagus is often the result of chronic reflux disease. When acid continuously backs up into the esophagus, it wears down the natural lining. This can cause a condition called Barrett's esophagus in which the body replaces the normal esophageal lining with one similar to that found in the intestines. People who develop Barrett's are at a higher risk of developing adenocarcinoma.
Transhiatal esophagectomy, or THE, is an operation in which most of the esophagus is removed without the need to open the chest, and swallowing is restored by pulling the stomach to the neck and connecting it there to the remaining esophagus. THE is used to treat esophageal cancer and Barrett's esophagus with severe precancerous changes. It was originally developed at the University of Michigan as a surgical alternative to removing the esophagus by going through the chest, a much more difficult operation for the patient.
The researchers sought to determine if THE is a safe procedure for the growing number of obese patients requiring esophageal surgery. They pulled the records of 133 profoundly obese patients who had this surgery at U-M between 1977 and 2006. Profound obesity was defined as a body mass index of 35 or more. Those 133 patients were matched to a randomly selected control group of non-obese patients undergoing the same procedure. Both groups were matched for factors including gender, age, year of operation and pre-existing medical conditions.
After comparing measures such as hospital length of stay, infection and mortality, the researchers found both groups had comparable outcomes. This suggests the THE procedure is safe to perform in obese patients. The study authors stress, however, that the results may be influenced by the high volume of patients U-M surgeons see for this procedure. U-M surgeons perform 120 to 150 transhiatal esophagectomies each year and have completed more than 2,000 of these procedures in total. Because the procedure in obese patients is more demanding on surgeons, the results may not be the same in hospitals that see relatively few patients in need of an esophagectomy.
"Profoundly obese patients undergoing a THE at a high-volume center can have surprisingly and acceptably low morbidity and mortality rates, similar to those of non-obese individuals matched for co-morbidities," says Orringer, head of the U-M Section of Thoracic Surgery and co-director of the Thoracic Oncology Program at the U-M Comprehensive Cancer Center.
Currently about 85 percent of esophageal cancers removed in this country are adenocarcinomas, most related to obesity and reflux disease, and 15 percent are squamous cell carcinomas, typically due to smoking or alcohol consumption. Two decades ago, those numbers were reversed.
"Reflux is an extraordinarily common problem now, and it's because we're a fat society. If heartburn is persistent or chronic, patients should have a thorough exam and endoscopy to see if they have developed Barrett's esophagus, which carries an increased risk of cancer and signals the need for close surveillance with periodic endoscopies and biopsies," Orringer says.