New Tests for Colon, Prostate Cancer Show Promise

Dennis Thompson wrote . . . . . . . . .

A pair of experimental tests could help doctors detect colon or prostate cancer with just a sample of blood or saliva.

One test examines a person’s blood for four biomarkers linked to inflammation. In a small study, it outperformed the fecal blood test now used in colon cancer screening, said lead researcher Dr. Mona Eldeeb, of Alexandria University Medical Research Institute in Egypt.

“These combined blood base markers could detect early cancer [of the] colon, especially if applied in a screening program,” she said.

The other test uses a man’s saliva to look for genetic material linked to prostate tumor growth, according to the Iranian researchers who developed it.

If approved in the United States, the tests could make screening and diagnosis for these cancers easier on patients, without the need for needle biopsy or colonoscopy, experts said.

“The exciting part of this study is that the [prostate cancer] test truly is noninvasive, requiring no need for needles as it relies on saliva that can be easily and repeatedly obtained,” said Dr. Corey Speers, a radiation oncologist at the University of Michigan’s Rogel Cancer Center in Ann Arbor.

The colon cancer test uses microscopic, color-coded beads to capture four inflammatory proteins from a blood sample. Laser technology then provides a count of the beads.

Eldeeb and her team tried the test with 35 patients with colon cancer and 52 people who were cancer-free.

They found that the proteins were at higher levels in the cancer patients, indicating that they could be used to screen for colon cancer without resorting to colonoscopy, Eldeeb said.

“This new test showed higher accurate results than the routinely used stool-based noninvasive test, and if used in combination with the fecal occult blood test gives very strong and accurate sensitivity with less need for colonoscopy,” she said.

The prostate cancer test searches saliva for eight RNA samples that indicate whether a man has developed prostate cancer or is simply suffering from age-related enlarged prostate. The research was led by Jamal Amri and Mona Alaee, from Tehran University of Medical Sciences in Iran.

The researchers tried the test on 180 men between the ages of 45 and 50, including 60 diagnosed with prostate cancer and 60 with enlarged prostate.

The study found that the saliva panel accurately sorted the men with prostate cancer from those with an enlarged prostate — something that up to now has required a needle biopsy.

“Of course, with all such preliminary studies questions still remain as to the accuracy and reliability of the test when you expand to a larger group of patients, and it isn’t yet ready for general adoption, but this represents an exciting first step,” said Speers, a spokesman for the American Society for Clinical Oncology.

He said future studies would seek to confirm these initial findings in a larger and more diverse set of men. They will also seek to determine appropriate cutoffs for levels of RNA in the saliva samples.

“We look forward to these confirmatory studies being completed,” Speers said.

Both reports were presented this week at the American Association for Clinical Chemistry (AACC) annual meeting, in Atlanta. Findings presented at medical meetings are considered preliminary until published in a peer-reviewed journal.

“These reports are very interesting early observations, and it will be exciting to see how they perform in follow-up studies,” AACC President Dr. Stephen Master said in a statement. “Of course, it’s important to note that both of these studies are preliminary, and both tests will need to be validated in larger studies before we can really know if they can be used in clinical practice or not.”

Source: HealthDay

Gut Bacteria Might be an Indicator of Colon Cancer Risk

A study published today in the journal Cell Host & Microbe reported that the increased presence of certain bacteria in a gut biome indicates a greater likelihood that colon polyps will become cancerous.

In his research, William DePaolo, associate professor at the University of Washington School of Medicine, tracked 40 patients who had undergone routine colonoscopies and had biopsies taken near the polyps to identify bacteria present at relatively higher levels compared with those of patients who were polyp-free. All the patients were between the ages 50 and 75, and 60% were women.

“The rising incidence of colorectal cancer is a major health concern, but little is known about the composition and role of microbiota associated with precancerous polyps,” the study states.

DePaolo’s research team found that a common bacteria, non-enterotoxigenic Bacteroides fragilis, was elevated in the mucosal biopsies of patients with polyps.

The research also found distinct microbial signatures distinguishing patients with polyps from those without polyps, and established a correlation between the amount of B. fragilis in the samples and the inflammation of small polyps.

Upon closer examination, DePaolo found that the B. fragilis from patients with polyps differed in its ability to induce inflammation compared to the B. fragilis from polyp-free individuals.

“The whole idea is that most people look at advanced colorectal cancer and think of the microbiome, but it’s hard to determine if the microbiome has changed and when it changed,” DePaolo said. “So we took an earlier look at the disease and asked when might the microbiome may be pushing a polyp toward cancer.”

Also, when people think of the microbiome and its role in disease, they often think of compositional changes where a potentially dangerous bacteria takes over, he added.

“What our data suggests is that, in order to survive within an environment where metabolic and inflammatory changes are occurring, a normally healthy gut and related bacteria may adapt in such a way that causes it to contribute to the inflammation rather than suppress it,” DePaolo explained.

Only 5% of the polyps in the colon actually turn out to be cancerous, he said. He said polyps seem to develop in the same areas of the colon repeatedly – and he theorized that in fact new screenings for colon cancer could look for key bacteria inhabiting the gut – and the amounts of this particular strain of B. fragilis – before pre-cancerous polyps even develop.

Colorectal cancer is the third leading cause of cancer in the United States, and its incidence is rising among younger adults. If a screening were available to test the microbes, before a polyp even appears, it could be a key factor to drive these rates down, DePaulo suggested.

The next step, he said, is to expand the study to 200 patients to determine whether a fecal sample might be used as a surrogate for the mucosal biopsy.

Source: University of Washington

Vitamin D Might Help Prevent Early-Onset Colon Cancer

Foods rich in vitamin D may help protect younger adults against colon cancer, researchers report.

While colon cancer is decreasing overall, cases among younger adults have been on the rise. The trends dovetail with a decline in vitamin D intake from foods such as fish, mushrooms, eggs and milk.

There is growing evidence of a link between vitamin D and risk of colon cancer death, but little research on whether vitamin D intake is associated with the risk of young-onset (before age 50) colon cancer.

“Because vitamin D deficiency has been steadily increasing over the past few years, we wondered whether this could be contributing to the rising rates” of colon cancer in younger people, said study co-senior author Dr. Kimmie Ng, director of the Young-Onset Colorectal Cancer Center at Dana-Farber Cancer Institute in Boston.

The study found that vitamin D intake of 300 IU per day or more — roughly equivalent to three 8-ounce glasses of milk — was associated with roughly a 50% lower risk of developing young-onset colon cancer.

Higher vitamin D intake were also associated with a lower risk of potentially precancerous colon polyps detected before age 50.

The findings are based on data from more than 94,000 women who were part of a long-term study that began in 1989. They were 25 to 42 years of age when the study began.

The study — recently published online in the journal Gastroenterology — is the first to make the connection between vitamin D levels and risk of young-onset colon cancer, researchers said.

They didn’t find a significant link between vitamin D intake and colon cancer risk after age 50, and they said more study is needed to determine if vitamin D actually provides greater protection against young-onset colon cancer than against it later on.

“Our results further support that vitamin D may be important in younger adults for health and possibly colorectal cancer prevention,” Ng said.

She said it is critical to understand the risk factors associated with young-onset colon cancer so informed decisions about lifestyle and diet can be made and high-risk individuals can receive earlier screening.

The findings could lead to recommendations for higher vitamin D intake as an inexpensive addition to screening tests to prevent colon cancer in adults under 50, researchers said.

Source: HealthDay

Too Little Sunlight, Vitamin D May Raise Colon Cancer Risk

Robert Preidt and Ernie Mundell wrote . . . . . . . . .

New research finds that countries with more cloudy days tend to have higher colon cancer rates. Lower levels of vitamin D, the “sunshine vitamin,” may be to blame.

So, boosting your vitamin D levels through exposure to sunlight could help reduce your risk of colon cancer, according to researchers at the University of California, San Diego.

“Differences in UVB [ultraviolet-B] light accounted for a large amount of the variation we saw in colorectal cancer rates, especially for people over age 45,” said study co-author Raphael Cuomo. His team published its findings July 4 in the journal BMC Public Health.

Cuomo stressed the the data cant prove cause-and-effect and is “still preliminary.” But “it may be that older individuals, in particular, may reduce their risk of colorectal cancer by correcting deficiencies in vitamin D,” Cuomo said in a journal news release.

Human skin manufactures vitamin D naturally upon contact with sunlight, and having an insufficient level of the nutrient has been tied to higher risk for a number of health issues.

What about colon cancer? To find out, the San Diego team tracked data from 186 countries to assess possible associations between local exposures to UVB light from the sun and colon cancer risk.

They found a significant association between lower UVB exposure and higher rates of the cancer among people ages 0 to over 75. After accounting for factors such as skin pigmentation, life expectancy and smoking, the association between lower UVB and risk of colorectal cancer remained significant for those older than 45, Cuomo’s group said.

They noted that other factors that may affect UVB exposure and vitamin D levels — such as use of vitamin D supplements, the clothing people wear and even air pollution — weren’t included in the study.

Dr. Elena Ivanina, a gastroenterologist at Lenox Hill Hospital in New York City, called the findings “provocative.” She wasn’t involved in the research.

“It is difficult to draw any steadfast conclusions from this study, but it certainly raises a thought-provoking consideration of the role that vitamin D plays in colorectal cancer formation,” Ivanina said. She said it might add a bit more impetus for anyone already “contemplating a move to a sunnier climate.”

Source: HealthDay

Study: Lots of Sugary Drinks Doubles Younger Women’s Colon Cancer Risk

Denise Mann wrote . . . . . . . . .

Rates of colon cancer among young Americans are on the rise, and a new study suggests that drinking too many sugary beverages may be to blame — at least for women.

Women who drank two or more sugar-sweetened beverages such as soda, fruity drinks or sports and energy drinks per day had double the risk of developing colon cancer before the age of 50, compared to women who consumed one or fewer sugary drinks per week.

“On top of the well-known adverse metabolic and health consequences of sugar-sweetened beverages, our findings have added another reason to avoid sugar-sweetened beverages,” said study author Yin Cao, an associate professor of surgery at the Washington University School of Medicine in St. Louis.

The study included more than 95,000 women from the ongoing Nurses’ Health Study II. The nurses were aged 25 through 42 when the study began in 1989 and provided information on their diet every four years for nearly 25 years.

Of these, 41,272 reported on what, and how much, they drank in their teen years. During 24 years of follow-up, 109 women developed colon cancer before turning 50.

Having a higher intake of sugar-sweetened drinks in adulthood was associated with a higher risk of the disease, even after researchers controlled for other factors that may affect colon cancer risk such as a family history. This risk was even greater when women consumed sodas and other sugary drinks during their teen years.

Each daily serving in adulthood was associated with a 16% higher risk of colon cancer, but when women were aged 13 to 18, each drink was linked to a 32% increased risk of developing colon cancer before 50, the study found.

But substituting sugar-sweetened drinks with artificially sweetened beverages, coffee or milk was associated with a 17% to 36% lower risk of developing colon cancer before age of 50, the study found.

“Reducing sugar-sweetened beverage intake and/or replacing sugar-sweetened beverages with other healthier beverages would be a better and wiser choice for long-term health,” Cao said.

The new study was not designed to say how, or even if, drinking sugary beverages causes colon cancer risk to rise, but some theories exist. People who consume sugary beverages are more likely to be overweight or obese and have type 2 diabetes, all of which can up risk for early-onset colon cancer. The high-fructose corn syrup in these drinks may also promote the development of colon cancer in its own right, Cao said.

The research does have its share of limitations. Participants were predominantly white women, and as a result, the findings may not apply to men or women of other ethnicities.

The study was published online in the journal Gut.

Researchers not involved with the new study are quick to point out that only an association was seen, and that more data is needed to draw any definitive conclusions about the role that sugary drinks play in promoting early-onset colon cancer.

“Clearly more research is needed before we can give this a stamp of approval and say with confidence that this association is actually causation,” said Dr. Will Bulsiewicz, a Mount Pleasant, S.C.-based gastroenterologist. “No one thinks sugar-sweetened beverages are health-promoting [and] you should reduce your sugar-sweetened beverage intake as much as possible.”

Dr. Patricio Polanco, an assistant professor in the division of surgical oncology in the department of surgery at UT Southwestern Medical Center in Dallas, agreed.

“Sugar-sweetened beverages cause a bunch of other conditions such as obesity and type 2 diabetes, and now we have more data that they could be related to colon cancer, too,” Polanco said.

Exactly why colon cancer is on the rise in younger people is not fully understood. Lifestyle factors such as higher rates of obesity and possibly greater consumption of sugar-sweetened beverages may play a role. “We still believe there may be some genetic contribution that has not yet been characterized,” he said.

The best way to protect yourself from colon cancer is to undergo regular screening, Polanco stressed.

Due to the rise in colon cancer in young people, the American Cancer Society now recommends regular screening at age 45 for people at average risk for the disease.

Source: HealthDay