Adenocarcinoma of the Esophagus (EPIDEMIOLOGY)
The incidence of adenocarcinoma of the esophagus has increased 300% to 500%
in the western world during the last 30 to 40 years. In 2002, approximately
half of 13100 anticipated esophageal cancers are expected to be adenocarcinoma.
The national cancer institute has reported a 5-year survival of only 11% for
this cancer.
Studies show a dose response relationship between frequency of reflux symptoms
and risk of adenocarcinoma (Lagergren J, Bergstrom R, Lindgren A, Nyren
O. Symptomatic gastroesophageal reflux as a risk factor for esophageal adenocarcinoma.
N Engl J Med. 1999; 340:825-31). In Lagergren study persons with long-standing (more than 20 years), severe (daily and nocturnal) reflux had an odds ratio
of 43.5 for esophageal adenocarcinoma. They have also shown an association
between this disease and obesity. The same group demonstrated associations
between medications that relaxes the lower esophageal sphincter (LES) and results
in more reflux and increased incidence of this carcinoma. Lagergren group calculated
that 15490 men of any age and 5570 men older than 60 years of age would need
to use the medications that relax LES more than 5 years for one person to develop
esophageal adenocarcinoma. With such a low incidence medical practice will
probably not be affected since the potential benefits of these medications
will out-weight their risk.
Although these studies report eye-catching
results for relative risk, it is the absolute risk that more accurately describes
any individual’s risk
of getting cancer. Therefore, the annual cancer incidence rate for reflux patient
older than 50 years is 6500 cases for every 10-million reflux patient at risk,
or 0.00065 cases per patient annually. Another problem in Lagergren study was
that 40% of individual with adenocarcinoma did not have at least weekly heartburn.
Translating to the more than 10 million patients with weekly reflux would have
only 3900 of the 6500 annual cases of esophageal adenocarcinoma, a risk of
only 0.00039 cases per reflux patient annually.
In Barrett esophagus the relative risk of cancer is 40-125 times higher than
general population. The absolute risk of any given patient with Barrett esophagus
developing cancer in a year is approximately 1 in 200.
Aggressive evaluation and therapy in persons with GERD is indicated to alleviate
symptoms, improve quality of life and decrease risk for cancer. Patients with
long standing severe heartburn, those with reflux who develop the alarm
symptoms of difficulty with swallowing, painful swallowing, frequent vomiting,
unexplained
weight loss, poor appetite and blood loss anemia should consult their physician
ASAP. Patients with known Barrett esophagus need to see and follow the advise
of their gastroenterologist for periodic surveillance, particularly if white
male and more than 40 years of age.
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