Signs of cancer can appear long before diagnosis, study shows |
Research into genetic mutations suggests the possibility of tests that would detect cancer earlier
Feb 5, 2020
The Guardian – Early signs of cancer can appear years or even decades before diagnosis, according to the most comprehensive investigation to date of the genetic mutations that cause healthy cells to turn malignant.
The findings, based on samples from more than 2,500 tumours and 38 cancer types, reveal a longer-than-expected window of opportunity in which patients could potentially be tested and treated at the earliest stages of the disease.
The work was carried out as part of the Pan-Cancer Analysis of Whole Genomes project, the most comprehensive study of cancer genetics to date.
“What’s extraordinary is how some of the genetic changes appear to have occurred many years before diagnosis, long before any other signs that a cancer may develop, and perhaps even in apparently normal tissue,” said Clemency Jolly, a co-author of the research based at the Francis Crick Institute in London.
“Unlocking these patterns means it should now be possible to develop new diagnostic tests that pick up signs of cancer much earlier,” said Peter Van Loo, co-lead author, also of the Crick Institute. “There is a window of opportunity.”
The discovery that the seeds of cancer are often sown many years before the first symptoms arise will not change cancer screening in the immediate term.
But it points to the possibility that those at risk could be spotted far earlier.
The study revealed that about half of the earliest mutations occurred in just nine genes, meaning there is a relatively small pool of common genes that serve as triggers for cells to diverge from healthy development to a path towards cancer.
It might be possible, in future, to pick up such mutations using so-called liquid biopsies – genetic tests that detect mutations in free-floating DNA carried in the blood that can indicate the presence of tumours elsewhere in the body. Read more.
GETTING CANCER – NOT WHAT WE WANT FOR YOU
Cancer prevention: 7 tips to reduce your risk
Concerned about cancer prevention? Take charge by making changes such as eating a healthy diet and getting regular screenings.
By Mayo Clinic Staff
You’ve probably heard conflicting reports about cancer prevention. Sometimes a specific cancer-prevention tip recommended in one study is advised against in another.
Often, what’s known about cancer prevention is still evolving. However, it’s well-accepted that your chances of developing cancer are affected by the lifestyle choices you make.
So if you’re interested in preventing cancer, take comfort in the fact that simple lifestyle changes can make a difference. Consider these cancer-prevention tips.
1. Don’t use tobacco
Using any type of tobacco puts you on a collision course with cancer.
- Smoking has been linked to various types of cancer — including cancer of the lung, mouth, throat, larynx, pancreas, bladder, cervix and kidney.
- Chewing tobacco has been linked to cancer of the oral cavity and pancreas. Even if you don’t use tobacco, exposure to secondhand smoke might increase your risk of lung cancer.
- Avoiding tobacco — or deciding to stop using it — is an important part of cancer prevention.
If you need help quitting tobacco, ask your doctor about stop-smoking products and other strategies for quitting.
2. Eat a healthy diet
Although making healthy selections at the grocery store and at mealtime can’t guarantee cancer prevention, it might reduce your risk. Consider these guidelines:
- Eat plenty of fruits and vegetables. Base your diet on fruits, vegetables and other foods from plant sources — such as whole grains and beans.
- Avoid obesity. Eat lighter and leaner by choosing fewer high-calorie foods, including refined sugars and fat from animal sources.
- If you choose to drink alcohol, do so only in moderation The risk of various types of cancer — including cancer of the breast, colon, lung, kidney and liver — increases with the amount of alcohol you drink and the length of time you’ve been drinking regularly.
- Limit processed meats. A report from the International Agency for Research on Cancer, the cancer agency of the World Health Organization, concluded that eating large amounts of processed meat can slightly increase the risk of certain types of cancer.
- In addition, women who eat a Mediterranean diet supplemented with extra-virgin olive oil and mixed nuts might have a reduced risk of breast cancer. The Mediterranean diet focuses mostly on plant-based foods, such as fruits and vegetables, whole grains, legumes, and nuts. People who follow the Mediterranean diet choose healthy fats, such as olive oil, over butter and fish instead of red meat.
3. Maintain a healthy weight and be physically active
Maintaining a healthy weight might lower the risk of various types of cancer, including cancer of the breast, prostate, lung, colon and kidney.
Physical activity counts, too. In addition to helping you control your weight, physical activity on its own might lower the risk of breast cancer and colon cancer.
Adults who participate in any amount of physical activity gain some health benefits. But for substantial health benefits, strive to get at least 150 minutes a week of moderate aerobic activity or 75 minutes a week of vigorous aerobic activity. You can also do a combination of moderate and vigorous activity. As a general goal, include at least 30 minutes of physical activity in your daily routine — and if you can do more, even better.
4. Protect yourself from the sun
Skin cancer is one of the most common kinds of cancer — and one of the most preventable. Try these tips:
- Avoid midday sun. Stay out of the sun between 10 a.m. and 4 p.m., when the sun’s rays are strongest.
- Stay in the shade. When you’re outdoors, stay in the shade as much as possible. Sunglasses and a broad-brimmed hat help, too.
- Cover exposed areas. Wear tightly woven, loose fitting clothing that covers as much of your skin as possible. Opt for bright or dark colors, which reflect more ultraviolet radiation than do pastels or bleached cotton.
- Don’t skimp on sunscreen. Use a broad-spectrum sunscreen with an SPF of at least 30, even on cloudy days. Apply sunscreen generously, and reapply every two hours — or more often if you’re swimming or perspiring.
- Avoid tanning beds and sunlamps. These are just as damaging as natural sunlight.
5. Get vaccinated
Cancer prevention includes protection from certain viral infections. Talk to your doctor about vaccination against:
- Hepatitis B. Hepatitis B can increase the risk of developing liver cancer. The hepatitis B vaccine is recommended for certain adults at high risk — such as adults who are sexually active but not in a mutually monogamous relationship, people with sexually transmitted infections, people who use intravenous drugs, men who have sex with men, and health care or public safety workers who might be exposed to infected blood or body fluids.
- Human papillomavirus (HPV). HPV is a sexually transmitted virus that can lead to cervical and other genital cancers as well as squamous cell cancers of the head and neck. The HPV vaccine is recommended for girls and boys ages 11 and 12. The U.S. Food and Drug Administration recently approved the use of vaccine Gardasil 9 for males and females ages 9 to 45.
6. Avoid risky behaviors
Another effective cancer prevention tactic is to avoid risky behaviors that can lead to infections that, in turn, might increase the risk of cancer. For example:
- Practice safe sex. Limit your number of sexual partners and use a condom when you have sex. The more sexual partners you have in your lifetime, the more likely you are to contract a sexually transmitted infection — such as HIV or HPV.
- People who have HIV or AIDS have a higher risk of cancer of the anus, liver and lung.
- HPV is most often associated with cervical cancer, but it might also increase the risk of cancer of the anus, penis, throat, vulva and vagina.
- Don’t share needles. Sharing needles with people who use intravenous drugs can lead to HIV, as well as hepatitis B and hepatitis C — which can increase the risk of liver cancer.
If you’re concerned about drug misuse or addiction, seek professional help.
7. Get regular medical care
Regular self-exams and screenings for various types of cancers — such as cancer of the skin, colon, cervix and breast — can increase your chances of discovering cancer early, when treatment is most likely to be successful. Ask your doctor about the best cancer screening schedule for you. SOURCE.