January 31, 2007 — The incidence of esophageal cancer has risen dramatically in the United States, as obesity has reached epidemic proportions and led to increases in chronic reflux disease, researchers from the University of Michigan told the Society of Thoracic Surgeons 43rd Annual Meeting, in San Diego, yesterday.
The team also reported that a surgical technique developed at the university — transhiatal esophagectomy, which avoids opening up the chest cavity — is as safe and successful in their hands in patients who are profoundly obese as in leaner patients. "But you must bear in mind that we are a high-volume center, and our surgeons are performing 150 to 200 of these operations each year," the head of the team, Mark Orringer, MD, told Medscape in an interview. "These results are not generalizable to a community hospital where a surgeon performs maybe 1 or 2 of these procedures a year."
Obesity Has Changed Nature of Esophageal Cancer
"The nature of esophageal cancer has changed, and the incidence rates have virtually flipped over," Dr. Orringer commented. "Whereas 20 years ago, most esophageal cancer was squamous cell carcinoma in people who drank alcohol and smoked excessively and only a small portion was adenocarcinoma, now the majority of cases, about 85%, of esophageal cancer are adenocarcinomas resulting from reflux disease and the obesity epidemic."
Obesity increases the risk of gastroesophageal reflux, and the acid that backs into the esophagus wears away the squamous cell lining. Eventually, the body starts to replace it with Barrett's mucosa, which greatly increases the risk of cancer, Dr. Orringer explained.
The incidence of adenocarcinomas has increased by about 350% in the past 30 years, closely following the "horrendous epidemic of obesity that we've been seeing, both in the United States and in Europe."
Surgical treatment involves removal of most of the esophagus, and the standard approach is to enter via the pulmonary cavity. The technique of transhiatal esophagectomy, developed at the University of Michigan during the mid-1970s, involves incisions in the neck and the upper abdomen but leaves the pulmonary cavity intact, which decreases both morbidity and mortality.
However, obesity is a relative contraindication for abdominal hiatus hernia surgery, and Dr. Orringer's team wondered whether the increasing size of the patients they were operating on was putting them at risk. At yesterday's meeting, one of the team, medical student Christopher Scipione, presented the results of an analysis to show that safety and the success rate were not affected. The outcomes in 133 patients with a body-mass index (BMI) greater than 35, classified as profoundly obese by the World Health Organization, were similar to those for a group of nonobese controls (BMI 18.5 – 30) who were "very carefully matched for tumor type and size, comorbidity, and age and sex," said Dr. Orringer.
"However, this not to say that the operation is the same in the fatter patients," he commented. The operation is more difficult and takes longer to perform in profoundly obese patients (5 to 6 hours rather than 3 to 3.5) and is physically more demanding and stressful for the surgeon. Also, it requires specially developed instruments, such as extra long retractors and scissors, he said. "Surgery is a manual skill, and we have an experienced team of surgeons who do a lot of these operations," he emphasized. "We found that, in our hands and with appropriate instrumentation, the morbidity and outcomes were similar in profoundly obese patients."
Society of Thoracic Surgeons 43rd Annual Meeting: Abstract 77. Presented January 30, 2007.
Medscape Medical News © 2007
Cite this: Zosia Chustecka. Huge Rise in Esophageal Cancer Rates Because of Obesity - Medscape - Jan 31, 2007.