Cut Inflammation, Cut Cancer Risk?

< Apr. 18, 2007 > -- Two studies presented at the American Association for Cancer Research 2007 annual meeting suggest that reducing inflammation may help to prevent cancer.

Both studies were conducted by researchers at the Mayo Clinic.

One study found that women who regularly used aspirin developed fewer cancers than women who did not use the anti-inflammatory medication.

Another study found that there may be an association between lung inflammation seen in asthma and increased risk of breast cancer spreading to the lungs.

Both studies offer hope that managing inflammation can help control cancer.

Regular Aspirin Use and Cancer Risk

The first study looked at more than 22,500 cancer-free postmenopausal women who took part in the Iowa Women's Health Study. The study participants provided information on aspirin and non-steroidal anti-inflammatory medication (NSAIDs) use.

NSAIDs include commonly used over-the-counter (OTC) medications such as ibuprofen and naproxen.

A decade later, women who regularly used aspirin were 16 percent less likely to have developed cancer and 13 percent less likely to have died of cancer than women who did not use aspirin, the researchers found.

This same benefit was not seen in women who regularly used NSAIDs other than aspirin, say the researchers at the Mayo Clinic in Rochester, Minn.

And while aspirin helped protect former and "never smokers" from cancer, that was not the case for women who were active smokers.

The findings do not mean that women should toss aside their NSAIDs or start taking aspirin on a regular basis, the researchers say.

"This is just one study. However, it does provide provocative evidence that regular aspirin use may play a role in preventing the most common chronic diseases in western countries, namely cancer and heart disease," says study lead author Dr. Aditya Bardia.

Previous studies have evaluated whether aspirin or other NSAIDs prevent specific cancers, such as breast cancer. "But this study is unique because we were able to evaluate comprehensive endpoints such as total cancer incidence and cancer mortality, which are more clinically relevant outcomes for patients," Dr. Bardia says.

Breast Cancer Spread, Asthma May Be Linked

In the second study, researchers at the Mayo Clinic in Arizona found that there may be an association between lung inflammation seen in asthma and increased risk of breast cancer spreading to the lungs.

The study, which was conducted in mice and supported by an ongoing examination of breast cancer patient records, suggests that breast cancer patients with asthma may be able to reduce the risk of cancer spread by using inhaler medications.

"A link between pulmonary inflammation and lung metastasis would not only have significant effects on patients' diagnosis and care, but will also immediately affect the way breast cancer patients are treated," says study author Dr. Anna Taranova, a senior research fellow.

"Those with asthma might be able to reduce their risk of lung metastasis, and increase their survival, with aggressive corticosteroid treatment," she says.

This connection between asthma-linked lung inflammation and cancer spread may also occur in other types of cancers, Dr. Taranova says.

She adds, "We suspect that the relationship between lung inflammation and metastasis will not be limited to breast cancer patients."

The researchers are now working with epidemiologists at Mayo Clinic Rochester to determine if breast cancer patients with lung metastasis had higher than normal rates of asthma.

To date, they have found "productive and provocative results," Dr. Taranova says: over 20 percent of women with breast cancer who developed lung metastasis also appear to have had a previous diagnosis of asthma. The typical frequency of asthma occurrence in US women is, at most, eight percent, she says.

"Our long term goal is to continue this detailed retrospective study of breast cancer patients, eventually translating these studies into a multi-center prospective examination of cancer patients," Dr. Taranova says. "We want to define the specific parameters that link lung metastasis and pulmonary disease."

Always consult your physician for more information.

Risk Factors for Cancer

Some cancers, particularly in adults, have been associated with certain risk factors.

A risk factor is anything that may increase a person's chance of developing a disease. A risk factor does not necessarily cause the disease, but it may make the body less resistant to it.

Persons who have an increased risk of developing cancer can help to protect themselves by scheduling regular screenings and check-ups with their physician and avoiding certain risk factors. Cancer treatment has been proven to be more effective when the cancer is detected early.

The following risk factors and mechanisms have been proposed as contributing to the development of cancer:

• Lifestyle and environmental factors such as smoking, high-fat diet, exposure to ultraviolet light (UV radiation from the sun), or exposure to chemicals (cancer-causing substances) in the work place over long periods of time may be risk factors for some adult cancers. Most children with cancer, however, are too young to have been exposed to these lifestyle factors for any extended time.

• Family history, inheritance, and genetics may play an important role in some adult and childhood cancers. It is possible for cancer of varying forms to be present more than once in a family. Some gene alterations are inherited. However, this does not necessarily mean that the person will develop cancer. It indicates that the chance of developing cancer increases. It is unknown in these circumstances if the disease is caused by a genetic mutation, other factors, or simply coincidence.

• Exposures to certain viruses, such as the human papillomavirus (HPV) and human immunodeficiency virus (HIV; the virus that causes acquired immune deficiency, or AIDS), and the herpes virus have been linked to an increased risk of developing certain types of cancers. Possibly, the virus alters a cell in some way. That cell then reproduces an altered cell and, eventually, these alterations become a cancer cell that reproduces more cancer cells. Cancer is not contagious and a person cannot contract cancer from another person who has the disease.

• Environmental exposures such as pesticides, fertilizers, and power lines have been researched for a direct link to childhood cancers. There has been evidence of cancer occurring among non-related children in certain neighborhoods and/or cities. Whether prenatal or infant exposure to these agents causes cancer, or whether it is a coincidence, is unknown.

Always consult your physician for more information.