Answers in a drop of blood

This article appeared in Scope magazine

Genetic testing available at the Loma Linda University Cancer Center offers the best chance of prevention or early detection in people with high risk factors , such as a strong family history.

DNA in the blood or saliva can reveal information on dozens of genes, identifying genetic abnormalities that increase the risk of cancer significantly more than the general population. The Cancer Center uses genetic testing, where indicated, for certain types of cancer, including breast, ovarian, uterine, prostate, colon and pancreatic cancers, that can all exist in families.

This test is really a case where knowledge equals power, says Sharon Lum, MD, medical director of the Breast Health Center at the Cancer Center.

"These results are achievable," she says. "They are more exploitable than most things we do in medicine."

For many cancers, the Cancer Center can test both previously diagnosed patients and those at high risk of harboring a cancerous gene . For these, the results of genetic testing may indicate the need for more frequent cancer screening than the general population, or for preventive measures. For the former, genetic testing can influence the treatment they receive to reduce the risk of cancer recurrence.

In the case of breast cancer, for example, which can strike both men and women, a patient with a BRCA1 or BRCA2 gene mutation is about five times more likely to be has cancer as BRCA 1 or 2 mutations.

Family members may also be positively impacted by the discovery of genetic mutations, revealing whether they should also be tested.

Lum chose to be tested herself because her father carries the BRCA1 genetic mutation, which increases the risk of cancer of the ovary, breast, prostate and pancreas. Fortunately, the mutation was not transmitted to him.

Genetic testing technology has evolved rapidly in recent years, making them faster and more affordable. Because it uses multigenic test panels, the Cancer Center sometimes discovers that a patient has a high risk for a different type of cancer than the one for which it was tested.

"With a drop of blood, you can literally test hundreds of different things," says Lum.

Although these tests are also available directly to consumers, Lum warns that these companies may not meet the high standards of laboratories used by hospitals, geneticists and physicians. These companies also can not provide the necessary medical follow-up.

The Cancer Center recommends that people discuss their cancer risks with a doctor. A statement to start the conversation can be simple, like "I just want to make sure we do not forget something about cancer screening."

When genetic testing is indicated, Lum says that this proves a second adage beyond "knowledge is power". Traced back to the 13th century, the 800-year-old wisdom says, "An ounce of prevention is worth a pound of healing."