Reseachers uncover new findings about esophageal cancer
A recent study led by researchers at Dana-Farber Cancer Institute reveals new findings on esophageal adenocarcinoma, a cancer whose incidence has increased dramatically in recent years. The research comes with a possible explanation for this alarming increase in the incidence of esophageal adenocarcinoma.
Statistics show that over the last 30 years the incidence of esophageal cancer increased approximately about 600 times in the United States of America. It is believed that an important risk factor for esophageal adenocarcinoma is gastroesophageal reflux disease. Gastroesophageal reflux disease involves the presence of stomach acid into the esophagus, which damages the lining of the esophagus. This condition can sometimes result in Barrett’s esophagus which is a premalignant condition for esophageal cancer.
Adam Bass, MD, of Dana-Farber and the Broad Institute, who is co-senior author of the paper, said that esophageal adenocarcinoma, especially those located at the junction between the esophagus and stomach, was extremely rare 40 years ago but now there are about 15,000 new cases that occur each year in the United States. He pointed out the fact that unfortunately esophageal adenocarcinoma is a cancer with poor prognosis as 5-year survival rate is only 15%. Although the incidence has risen dramatically in recent decades, in terms of treatment there have not been many improvements. Bass explained that the purpose of the study was to find other genetic abnormalities that cause this type of cancer, to find new methods of early diagnosis and more effective treatment.
It is not clear why the incidence of esophageal adenocarcinoma has increased so much in recent years, although there are several assumptions in this regard. It seems that an important factor in the development of this cancer is obesity, especially in men. It seems that obesity causes increased abdominal pressure which causes lower esophageal sphincter incontinence.
To find out more about the genetic basis of cancer of the esophagus researchers conducted a study in which they analyzed specific sections of DNA from 149 patients with esophageal adenocarcinoma. In addition, in 15 of these patients researchers sequenced the entire genome. Gad Getz, PhD, of the Broad Institute and Massachusetts General Hospital, co-author of the study, said the study revealed a pattern of DNA changes that has never been seen before. These DNA changes are in fact some mutations that occur in esophageal cells and it seems that these mutations are caused by reflux of stomach acid. “Identifying the mutated genes within these tumors will help us understand the underlying biology of the disease,” said Bass.