Biomarkers are promising predictors

A lot of bad things have been happening lately. I don't know about your psyche, but I have had my share of tsunami nightmares. With no warning, a wave looms up suddenly and sweeps me, my loved ones and my favorite pillow out to sea. Personally, I like to know in advance when I need to run for the hills.

What is our early warning signals when it comes to killer diseases? Is it possible that our bodies hold secrets that can foretell an impending natural disaster such as cancer?

Medical researchers are on the case, and what they are increasingly looking for are "biomarkers," chemicals produced by the body that can indicate the very beginning stages of disease.

The National Cancer Institute recently dedicated almost $10 million to finding new biomarkers for cancer. They are being studied for all sorts of cancers -- including breast, ovarian, colon and kidney -- and for predicting both the onset of the cancer and its progression once diagnosed.

New on the cutting edge are studies targeting blood platelet substances. When measured, these markers may indicate the early presence of cancer in the body. What is exciting about this is that, if successful, these biomarkers will tip doctors off to potential cancerous tumors before they are formed.

This means that cancer can be treated preventively, much like heart disease is now treated. Medicines could be prescribed to prevent the onset of cancer by preventing the formation of blood vessels that could feed the formation of a cancerous tumor. This is greatly preferable to gunning for already-formed tumors with chemotherapy and all of its nasty side effects.

One of the biomarkers that you are probably already familiar with is the prostate specific antigen (PSA) test. It has been widely used by the medical profession to portend prostate cancer. Many men have been saved by this early warning signal.

The much-used PSA biomarker has become controversial, however. None other than Dr. Stamey, the Stanford University inventor of the test, has recently published a paper claiming that the PSA test only detects enlarged prostates, not cancer.

Many experts will agree that the PSA test is an imperfect biomarker for indicating prostate cancer and often results in unnecessary and invasive biopsies. Doctors will tell you that they have had patients with prostate cancer showing a normal PSA and others with a high PSA who are without cancer.

The fact that biomarkers are either in their infancy or imperfect only points to the fact that we cannot overly rely on high-tech science.

Staying in touch with a competent physician is important. Only he or she will be able to assess if you need to be screened for cancer. We also need to be in touch with our own bodies.

Cancer rarely signals its onset with pain, so it is important to be aware of certain tell-tale symptoms, such as: changes in bowel or bladder habits, sores that fail to heal, unusual bleeding or discharge, unusual lumps, difficulty swallowing, obvious change in a wart or mole, nagging cough or hoarseness, unexplained changes in weight.

Finding "psychic" biomarkers in our body that can predict the onset of deadly diseases may sound so "next century." But the day may not be too far off when a simple home saliva test will tell us that Big Bad Cancer Wolf lurking right outside and give us the wonderful opportunity to bolt the door.

Dr. Michael O.L. Seabaugh, a Cape Girardeau native, is a clinical psychologist who lives and works in Santa Barbara, Calif. Contact him at mseabaugh@ semissourian.com.