Researchers are exploring new ways to detect and treat colon cancer, starting even before cancerous tumors form.
Individuals undergoing colonoscopies may soon be able to swallow a dye pill to help doctors better detect precancerous polyps, known as adenomas.
And a DNA vaccine paired with an antibody that boosts its immune effect may not only help your body fight back against late-stage colorectal cancer, it could also work to prevent cancers from forming in the first place.
Both approaches combine proven therapies in hopes of boosting their overall effectiveness against a disease that kills more than 50,000 people in the United States every year.
Both of these advancements will be unveiled at the Digestive Disease Week conference, which begins Saturday in Washington, D.C.
Catching colon cancer early
Early detection is key to preventing colorectal cancer deaths.
A dye called Methylene Blue MMX is sometimes used as part of colonoscopy procedures for high-risk patients.
The dye, sprayed on the colon wall during the colonoscopy, helps make precancerous polyps and cancerous tumors (carcinomas) more visible.
However, the dye is somewhat cumbersome to prepare and use.
So, researchers are testing a new method of dye administration: a swallowable pill.
The study found that adenomas and carcinomas were found in 56 percent of patients undergoing colonoscopies who swallowed a total of eight dye pills during their colonoscopy prep period. That compared with 47 percent of those who received colonoscopies minus the dye pill — an increase in adenoma detection rate (ADR) of about 9 percentage points.
Past studies have estimated that every 1 percent increase in ADR equates to a 3 percent decline in the incidence of colorectal cancer and a 5 percent decline in colon cancer fatalities.
Gastroenterologists were also able to spot more flat and smaller (less than 5 millimeter) lesions using the dye pill. Less than 6 percent of patients experienced side effects beyond the common, harmless discoloration of feces and urine, researchers reported.
“This is an important advance that should improve the quality of colonoscopies and reduce the risk for colon cancer,” Dr. Michael B. Wallace, professor of medicine and director of the Digestive Disease Research Program at the Mayo Clinic in Jacksonville, Florida, told Healthline.
Future research will compare the effectiveness of the pill to the sprayable dye, which Wallace noted is “not used very often” and only with high-risk patients, such as those with a genetic predisposition to colon cancer and those with chronic colitis.
The pill, on the other hand, has potential to be used as a routine part of all colonoscopies, Wallace said.
And while the sprayable dye is expensive — a typical treatment can cost around $450 — the pill could be covered as prescription medication under a patient’s health insurance.
A total of 1,205 colonoscopy patients took part in the study.
Aries Pharmaceuticals, the company that markets the sprayable Methylene Blue MMX, also developed the pill. It’s already in use to deliver time-released doses of drugs such as Uceris, which treats ulcerative colitis, directly to the colon.
Treating colon cancer at later stages
In the second study, researchers are combining an existing DNA vaccine, which sparks the body’s immune response against polyps and tumors, with an antibody approved by the U.S. Food and Drug Administration (FDA) that removes the “brakes” on your immune system that normally limit attacks on cancer cells.
Researchers say the combination therapy could benefit patients with late-stage colorectal cancer and perhaps be administered to high-risk patients to prevent polyps from forming in the first place.
“Immunology is taking center stage in the treatment of cancer,” Robert Ramsay, PhD, a lead researcher in the study and professor at the Peter MacCallum Cancer Centre at the University of Melbourne in Australia, told Healthline.
A similar combination of so-called “checkpoint immunotherapy” has been highly successful at treating melanoma, the deadliest form of skin cancer, he noted.
The vaccine and antibody approach can prompt an immune response on both cancerous tumors in the bowel and the metastatic tumors that they spawn.
“Once cancer has spread to other parts of the body, patients with colorectal cancer have few other viable options; therefore, this treatment could be life-changing for these patients,” said Toan Pham, a study researcher, PhD candidate, and research fellow at the Peter MacCallum Cancer Centre, in a press statement.
Like a vaccine against communicable diseases, the colon cancer vaccine could also be administered preventively to high-risk patients, such as those with a condition called familial adenomatous polyposis who developed multiple colon polyps.
It could even be given to patients who’ve had a precancerous polyp removed during routine colonoscopy.
“In the future there might be a vaccine you can take to avoid getting another polyp,” said Ramsay.
Ramsay added that, if successful, the combination therapy for colon cancer could have broader implications.
“We dream that we can expand the scope of this approach to other kinds of cancer,” said the 30-year veteran cancer researcher. “I’ve never been more excited about cancer management than I am right now.”
The dye study is about to enter phase III clinical trials, the final step before seeking FDA approval for use.
The vaccine and antibody combination will soon be tested on humans for the first time.