There's a lot of good news on the cancer front these days. People with the disease are living longer. There are more cancer champions in the United States than ever before.
Then there are some types of this horrible disease that are on the increase, and esophageal cancer is one of them. It's been on the rise since the 1970s.
We wondered why and ran into some interesting - and surprising - findings.
Most think the increasing incidence of a particular type of esophageal cancer is probably tied to obesity. There are other risk factors, like smoking, drinking, and genes.
What's the story?
What's an esophagus?
Here's a little anatomy lesson for background.
The esophagus is a stomach tube that's located just behind your breast bone. It's about 10 inches long, and its job is to move food from the throat to the stomach.
This tube has several layers: mucous membrane that's moist to help food travel from the mouth to the stomach; muscle layer that pushes the food down into the stomach; and an outer layer of connective tissue.
What is esophageal cancer?
Cancer starts in an inner layer of the esophagus and works out to other layers as it grows.
There are two types of esophageal cancer:
- Adenocarcinoma - starts in the cells that secrete fluids like mucus. This type of cancer shows up in the lower part of the esophagus close to the stomach.
- Squamous cell carcinoma - usually appears in the upper and middle part of the esophagus and is technically known as epidermoid carcinoma.
Adenocarcinoma is the most common type of esophageal cancer in the United States, and has been increasing since the 1970s.
Fewer Americans are developing squamous cell carcinoma, but it's the most common type of esophageal cancer found around the world.
Symptoms of either type of this cancer include painful or difficult swallowing, pain around the breast bone area, hoarseness or cough, weight loss, indigestion and heart burn.
Who gets esophageal cancer?
There are a number of risk factors for esophogeal adenocarcinoma, including:
- Being male - men are three times more likely than women to get this cancer.
- Heavy drinking - 3+ drinks a day
- Smoking and drinking together increases the odds even more.
- Acid reflux - when stomach acid flows back up into the esophagus. Over time, this acid can damage the tissue of the esophagus and can lead to adenocarcinoma.
- Barrett esophagus - what results from continual acid reflux. This condition damages the cells in the lower esophagus and increases the risks adenocarcinoma.
Yelena Y. Janjigian, MD, assistant attending physician in the Gastrointestinal Oncology Service at Memorial Sloan-Kettering Cancer Center in New York, told dailyRx, "There are also hereditary predispositions."
"In other words, of the millions of obese people in the US that smoke and drink alcohol, only a subset of patients develop esophageal adenocarcinoma, probably because these people are genetically more susceptible to these risk factors resulting in cancer," Dr. Janjigian said.
Esophageal cancer numbers
Here's where it gets interesting.
There's no question esophageal cancer cases are increasing in the United States.
According to a study that appeared in Cancer in November, 2000 - the number of cases of adenocarcinoma jumped 350 percent between 1974 to 1994. Annual rates per 100,000 population soared from 0.7 during 1974-1976 to 3.2 during 1992-1994.
Fast forward. A look at American Cancer Society (ACS) data shows that in 2007, there were an estimated 15,560 new cases of esophageal cancer and 13,940 deaths. In 2012, that estimate has grown to 17,460 new annual cases and 15,070 deaths. This 5-year trend accounts for about a 25 percent increase, or 5 percent a year.
What's causing the increases?
"The increase in incidence of esophageal adenocarcinoma is likely attributable to the obesity epidemic affecting the Western countries, as well as gastroesophageal reflux disease, Barrett’s esophagus, tobacco use and alcohol," Dr. Janjigian said.
dailyRx Contributing Expert, Herbert C. Wolfsen, MD professor of medicine at the Mayo Medical School and Chief of Gastrointestinal Endoscopy at the Mayo Clinic in Florida, agrees with Dr. Janjigian. "We have more acid blocker drugs than ever and fewer people smoke, so presumably obesity is an increasingly important factor," Dr. Wolfsen told dailyRx.
Teasing out the numbers
Just for fun, we looked at how these numbers break down by state, based on the ACS data. If you think of obesity, smoking, and drinking as being the major risk factors for the disease, then there's a disconnect.
Here are the top five states for esophageal adenocarcinoma:
- New Hampshire, which ranks toward the bottom - 33 out of 50 - for obesity
- Maine - ranks 27th in terms of obesity.
- Massachusetts - ranks 48 out of 50 for obesity
- Rhode Island - 42nd most obese state
- Iowa - 20 out of 50 for obesity.
On a global scale, esophageal is quite common:
- For men, it's the 6th leading cancer and cancer-related cause of death
- In developed countries, esophageal cancer ranks as the 8th leading cause of cancer deaths among men.
- In developing countries, the disease is much more common - 5th leading cancer and 4th leading cause of cancer deaths in men ; 8th leading cancer and 7th leading cause of cancer deaths in women.
So what does this mean? Simple. The increase in esophageal cancer is something of a mystery.
What you can do about esophageal cancer
As with so many cancers, lifestyle plays a critical role in lowering your risk of this particularly nasty cancer.
"Improved lifestyle habits, and a diet high in cereal fiber and other nutrients may have protective effect against esophageal cancer," Dr. Janjigian said.
"Patients with persistent acid reflux that does not improve with medication, unexplained weight loss associated with swallowing problems should seek medical attention," she added.
"While we’ve made progress, advanced cases of esophageal adenocarcinoma are difficult to treat, highlighting the need for better treatments and more research efforts in this area," Dr. Janjigian concludes.