Esophageal cancer causes and risk factors stop heartburn

The incidence of both types of esophageal cancer varies significantly around the world. The highest incidence of squamous cell carcinoma of the esophagus is in what’s been coined the Asian Esophageal Cancer Belt. This region includes areas such as Turkey, Iran, Kazakhstan, and central and northern China. The incidence is also very high in southeastern Africa.

Squamous cell carcinomas of the esophagus are roughly five times more common in people who smoke. Smoking is not, however, a risk factor for esophageal cancer in all parts of the world. For example, in China, it appears that smoking plays only a small role; dietary factors appear more important.

Like smoking, alcohol intake is a significant risk factor for squamous cell carcinoma of the esophagus in some parts of the world but not others.

Heavy alcohol intake is associated with a 1.8- to 7.4-fold increase in risk. Low to moderate alcohol intake, according to a 2018 study, is actually associated with a lower risk of developing the disease than for those who abstain.

The combination of smoking and drinking is the most significant risk factor for squamous cell carcinoma and is thought to account for around 90 percent of cases worldwide. The risk is higher than would be expected if you were to add up the risk of smoking plus heavy drinking alone (instead of being additive, the risk is multiplied).

Achalasia is a condition in which the muscular band around the lower part of the esophagus (the lower esophageal sphincter) doesn’t relax properly to allow food to leave the esophagus and enter the stomach. This results in food remaining in and stretching the lower esophagus. Achalasia is associated with a high risk of esophageal cancer, with cancer often occurring 15 to 20 years after the diagnosis.

Radiation therapy to the chest for conditions such as breast cancer or Hodgkin’s disease may increase risk. While women who have had radiation after a mastectomy have an elevated risk, this does not appear to be the case for women who have radiation to remaining breast tissue after a lumpectomy.

Drinking very hot beverages (much warmer than a typical cup of coffee) has long been thought to carry an increased risk. A 2018 study supported this belief, though drinking tea at high temperatures was a risk only when combined with excessive alcohol intake or smoking.

Speaking of beverages, you may have heard that soda can cause esophageal cancer by way of related heartburn. This possible connection was debunked by a study from the National Cancer Institute and subsequent studies that not only found no increased risk of squamous cell carcinoma or adenocarcinoma but potentially just the opposite.

Diet—especially a diet low in fruits and vegetables, and high in red and/or processed meat—is associated with a higher risk of both types of esophageal cancer, but the link is stronger with squamous cell carcinoma. With meats, the method of cooking also appears to be important, and cooking or grilling at high temperatures is associated with greater risk. Betel and areca nuts have also been associated with the development of esophageal cancer.

Human papillomavirus (HPV), the virus that causes cervical as well as some other cancers, may possibly be related to the development of squamous cell carcinoma. While researchers are uncertain if the virus is causative, it has been found in up to a third of esophageal cancers in Asia and parts of Africa. Thus far, HPV does not appear to be linked with esophageal cancer in the United States. Adenocarcinoma

Adenocarcinomas occur most often in the lower third of the esophagus and begin in glandular cells. Ordinarily, the lower third of the esophagus is lined with squamous cells, but chronic damage (such as chronic acid reflux) results in the transformation of these cells so that they appear more like the cells that line the stomach and intestines. Over time, these cells may become precancerous cells and then cancer cells. Adenocarcinomas have now surpassed squamous cell carcinomas in the United States, the United Kingdom, Australia, and Western Europe.

Acid reflux, or gastroesophageal reflux disease ( GERD), is a significant risk factor for esophageal adenocarcinoma, with roughly 30 percent of these cancers thought to be linked to the condition. It’s thought that between 0.5 percent and 1 percent of people with GERD will develop esophageal cancer.

Barrett’s esophagus is a condition in which the normal cells of the lower esophagus (squamous cells) are replaced with glandular cells like those present in the stomach and intestines. It is usually found in people who have longstanding chronic acid reflux and occurs in 6 percent to 14 percent of people with chronic GERD. Though estimates vary, roughly 1 in 100 to 1 in 200 people with Barrett’s esophagus will develop esophageal cancer each year. Like adenocarcinoma, Barrett’s esophagus is increasing in the United States.

Some studies (but not all) have shown a reduction in the risk of esophageal adenocarcinoma in people who have Barrett’s esophagus who have taken non-steroidal anti-inflammatory drugs (such as Advil, ibuprofen, proton pump inhibitors (such as Prilosec, omeprazole), or statin drugs (such as Lipitor, atorvastatin).

Being overweight or obese increases the risk of adenocarcinoma of the esophagus. According to a 2015 review, people who are overweight (body mass index of 25 to 29) are about 50 percent more likely to develop cancer, while those who are obese (body mass index of 30 or higher) are roughly twice as likely to develop esophageal cancer. Having type 2 diabetes may also increase risk, but it’s uncertain whether this is related to diabetes itself or co-occurring obesity.

Some medications are associated with either an increased or decreased risk of adenocarcinoma of the esophagus. The use of bisphosphonates (used for osteoporosis) may increase risk, as may the use of estrogen-only hormone replacement therapy. In contrast, the use of aspirin is associated with a decreased risk.