Colorectal Cancer Archive

Ask the doctors

Q. I have hemorrhoids. Could this increase my risk of colon cancer?

A. In short, no. Hemorrhoids don't cause or increase your risk for colon or rectal cancer. However, the two conditions may be mistaken for one another because they can produce similar symptoms, such as rectal bleeding, itching, and pain.

The US Preventive Services Task Force has updated its lung cancer screening guidelines, to open up the screening to a wider range of people based on their age and smoking history, with the goal of detecting more cancers and reducing deaths.

Research we're watching

Move your body more and skip the alcohol to reduce your risk of cancer, says the American Cancer Society in its new cancer prevention guidelines. The updated recommendations, published online June 9, 2020, by CA: A Cancer Journal for Clinicians, also recommend cutting down on sugar and red meat, based on a review of the most recent scientific evidence.

Specifically, the new guidelines say that instead of exercising moderately for 150 minutes a week or doing 75 minutes of vigorous activity, adults should try to squeeze in 150 to 300 minutes of moderate activity or 75 to 150 minutes of vigorous activity — and that the higher number should be the target. As for diet, people interested in reducing their risk of cancer should aim to eat more plants, including whole (not refined) grains and at least two-and-a-half cups of colorful fruits and vegetables each day, and less sugar and meat (specifically limiting processed and red meat whenever possible). In the past, the ACS recommended moderate alcohol intake, but the new guideline says it's better to avoid alcohol altogether if possible. People who do drink should still stick to the previous recommended limits: no more than one drink a day for women and two drinks a day for men.

News briefs

Eating a diet high in foods tied to inflammation — such as processed meat, sweets, and refined grains — is associated with many health problems, including an increased risk for colon cancer, heart disease, stroke, or diabetes. A Harvard study published online May 7, 2020, by Gastroenterology found another potential risk: Crohn's disease, a condition characterized by areas of inflammation throughout the large and small intestines. Researchers evaluated 30 years' worth of self-reported diet information from more than 208,000 men and women. Diets were scored based on foods that promote inflammation. Compared with people who had the lowest inflammatory diet scores, people with the highest scores had a 51% higher risk for developing Crohn's disease. The risk for Crohn's doubled among people who went from a low- to a high-inflammatory diet during the study. The study is observational and doesn't prove that an inflammatory diet causes Crohn's disease. But with so many other risks associated with foods that promote inflammation, it's important to eat as many foods that fight inflammation as possible. In other words, focus on whole, unprocessed foods with no added sugar — such as vegetables, fruits, whole grains, legumes (beans, lentils), fish, poultry, nuts, seeds, a little bit of low-fat dairy, and olive oil.

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Blood testing to detect early cancer may be closer to reality than ever before.

When it comes to most cancers, the sooner they're found, the better. "Identifying cancer in its earlier stages offers improved chances for treating it before it can grow and spread," says Dr. Brian Wolpin, director of the Gastrointestinal Cancer Center at Harvard-affiliated Dana-Farber Cancer Institute.

Unfortunately, there are not reliable tools to screen for most cancers. Examples of effective screening tests that do exist now include colonoscopies that look for polyps and early colorectal cancers, as well as imaging tests like mammograms for early signs of breast cancer and chest CT scans for localized lung cancer among former or current smokers.

News briefs

First it was certain blood pressure and heartburn drugs; now some medications used to treat type 2 diabetes are being recalled because of cancer concerns. The FDA warned in late May and early June 2020 that some lots of extended-release metformin may contain unacceptable levels of N-nitrosodimethylamine (NDMA), a possible cancer-causing chemical. At least five manufacturers are now issuing voluntary recalls of the medications. But if you take extended-release metformin, don't just stop on your own. Not all extended-release metformin products are affected by the voluntary recalls, and stopping any medication that controls blood sugar can be very dangerous. The FDA advises that you check in with your doctor or pharmacist. Ask if your medication is affected by the recall; if so, ask if you should switch to another version of the drug.

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Research we're watching

A new tool to identify people who might be at higher risk for pancreatic cancer could help doctors find cases earlier, when they are most treatable. Researchers from the Harvard T.H. Chan School of Public Health created a risk model that did a better job than current models of finding people at high risk for the disease. It takes into account clinical and genetic factors as well as blood levels of biomarkers (substances that could potentially indicate disease). To test the model researchers used data from four large clinical studies. They applied the tool to 500 known pancreatic cancer patients and more than 1,000 people without cancer. The researchers then assessed how well the tool would have predicted the risk of pancreatic cancer. Pancreatic cancer, which is the third leading cause of cancer death in the United States, is challenging to treat because most people already have advanced disease when they are diagnosed. It's hoped that identifying people who are at high risk will eventually allow doctors to screen these individuals to find cancers when they are smaller and more curable.

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In the journals

Scientists continue to explore the health benefits versus risks of aspirin therapy. One new analysis suggests that taking aspirin may protect against several types of digestive tract cancers. The results were published online April 1, 2020, by Annals of Oncology.

Researchers examined 113 observational studies of cancer in the general population. They found that individuals who took aspirin regularly — at least one or two tablets a week — had significantly lower rates of cancers of the bowel, stomach, gallbladder, esophagus, pancreas, and liver, compared with people who did not take aspirin.

Most people understand the risks of sun exposure, even if they do not regularly wear sunscreen, but getting younger people to pay attention to this concern can be difficult. A study chose a novel approach to this problem by appealing to teenagers’ vanity and focus on their appearance.