DNA trials may end mammograms, colonoscopies

Doc expects blood tests that predict cancer recurrences to have major effect on millions

In the not-so-distant future, a single blood test may be able to locate cancer.

Dr. Salvatore Iaquinta

At least that's the prediction of Dr. Salvatore Iaquinta, "Highway to Health" columnist for the Marin Independent Journal and a surgeon at Kaiser Permanente San Rafael.

Noting in a recent piece headlined "Closing in on cancer" that "we already have blood tests to monitor for cancer recurrences," Iaquinta forecasts the end of mammograms and colonoscopies.

Biomarkers "that expose the presence of otherwise invisible recurrences," he indicates, are already known for "certain ovarian, prostate, breast, liver and pancreatic cancers."

The same applies to some thyroid cancers.

But researchers at Johns Hopkins, he notes, have now "announced their success developing a 'liquid biopsy' — a blood test to screen for cancer DNA."

And "for patients with colon cancer, the screening test found about 90 percent of all stage 2, 3 and 4 cancers."

Iaquinta adds that it was almost as important that false positives didn't result.

And although the experimental tests for breast, lung and ovarian cancers didn't fare as well, they did find "at least 45 percent of stage 1 cancers for each of these tumor types," he writes.

Researchers at Stanford, the doctor maintains, "have done the same sort of profiling with some types of lymphoma."

And the "Institute of Cancer Research in London also found a tumor DNA for breast cancer and has announced they can detect recurrent disease eight months before standard tests reveal it."

In the meantime, a different group at Stanford "used a similar test to detect the effect of chemotherapy on women being treated for breast cancer. They found that a blood test could predict how the tumor was responding to treatment within two weeks of the start of treatment, far earlier than the standard methods."

The experimental process is not yet available to the general public and is still expensive, Iaquinta explains, "because of the cost of DNA sequencing. But like everything else tech, the price will come down as scientists find easier, faster ways to run the tests."

He concludes that "the ability to detect multiple cancers from a simple blood draw will have a profound effect on millions, and ultimately billions, of lives."

More information about experimental drugs and treatments can be found in "Rollercoaster: How a man can survive his partner's breast cancer," a VitalityPress book I, Woody Weingarten, aimed at caregivers.