New Test Better Than Current Methods for Detecting Recurrence of Colorectal Cancer
Dec. 6, 1999 (Cleveland) -- The presence of a specific protein may predict
the recurrence of colorectal cancer better than laboratory tests currently do,
according to a study published in the Dec. 6 issue of the journal Annals of
This is good news for patients with colorectal cancer who have had surgery
to remove their cancer, according to senior author Scott A. Waldman, MD, PhD,
FCP, especially since current laboratory testing for this cancer is far from
"The current state-of-the-art for staging colorectal cancer is good, but
it is not perfect. This imperfect approach sometimes results in patients being
diagnosed with a lower stage of disease than they actually have. This is not a
reflection of errors but, rather, the insensitivity of the current standard
techniques being employed," says Waldman. "However, there are new tools
being developed [that] harness the power of molecular biology to increase the
sensitivity to detect microscopic deposits of cancer hidden in tissues. ...
This information will be used to better predict the risk of developing
recurrent disease in the future and to more accurately identify patients who
could benefit from receiving chemotherapy."
Waldman and his colleagues at Thomas Jefferson University in Philadelphia
studied 21 patients who had undergone surgical removal of their colorectal
cancer. Of the 10 patients who had recurring cancer within three years of
surgery, the protein, known as guanylyl cyclase C messenger RNA (GCC mRNA), was
found in the lymph nodes of all of them. Moreover, it didn't show up in any of
the samples taken from the 11 patients who were disease-free for six years or
more after surgery.
These results were surprising, even to Waldman. "We expected that some
of the patients who developed recurrences would exhibit microscopic disease
using this test, but not all of them. As most folks in science and medicine
would say, it is never 100%! So these results really got my attention," he
The test used by the authors of this study is currently being developed into
a blood test that can detect microscopic deposits of cancer cells in patients
with colorectal cancer, says Waldman, in hopes of using GCC mRNA to detect any
cancer recurrences much earlier than previously possible.
- The current standard for testing for colorectal cancer is not always
- Researchers have developed a more sensitive test to predict the recurrence
of colon cancer, by looking for a specific protein called GCC mRNA.
- In a study of 31 patients who had undergone surgical removal of colon
cancer, the new test was 100% accurate in predicting who had recurrences and
who remained disease-free.