Cancer Essentials
Start here. It really is this short.
Most cancer information is written for people who already understand it. This is the other thing: 15 short pages, in plain words, that answer the questions people actually ask first. What is this cancer? What should I watch for? What raises the risk? Is there a test before symptoms start? And which of the things I have heard are simply not true?
Every page fits on one screen or two. Every fact on it comes from a US federal health agency, named at the bottom of the page with a link. Where those agencies say the evidence is thin or unsettled, we say that too, instead of rounding it up into advice.
Ten common cancers
One short page each. What it is, what to watch for, what raises risk, and whether there is a test for it before symptoms start.
- Breast CancerEarly breast cancer usually has no symptoms at all. That is the whole reason screening exists.
- Lung CancerSmoking causes most lung cancer. It does not cause all of it, and people who never smoked get it too.
- Prostate CancerMost prostate cancer grows very slowly. NCI says finding and treating it early may not help men live longer, which is why screening here is a decision, not a default.
- Colon and Rectal CancerThis one is different from the others. It usually starts as a growth that can be found and removed before it ever becomes cancer.
- Melanoma and Skin CancerSkin cancer is the most common cancer of all. Melanoma is the least common of the main types and the most likely to spread.
- Bladder CancerBlood in the urine is the main sign, and it is often painless. That is exactly why it gets ignored.
- Kidney CancerNCI says there may be no signs at all in the early stages. Many kidney cancers are found by accident, on a scan ordered for something else.
- Non-Hodgkin LymphomaIt is not one disease. Non-Hodgkin lymphoma is a group of cancers of the lymph system, and NCI says the outlook depends on which type it is.
- Uterine CancerBleeding after menopause is the sign that matters most. It is also the reason two-thirds of these cancers are caught early.
- Pancreatic CancerNCI says this one is difficult to diagnose early. The organ is hidden, the early symptoms are quiet, and there is no screening test.
The causes we can do something about
Most cancer risk is not in anyone's control. These four things are, at least partly, and federal sources are clear about them.
- TobaccoSmoking causes cancer in at least a dozen parts of the body, not just the lungs. And quitting helps at every age, including late.
- Vaccines That Prevent CancerTwo ordinary vaccines prevent infections that cause cancer. This is the closest thing to a cancer vaccine that exists, and it already sits in every pediatrician's fridge.
- Weight, Alcohol, and FoodAlcohol and body weight have strong, well-established links to cancer. Most other food claims you have heard do not, and NCI says so.
- Sun and UVCDC says too much UV from the sun or tanning beds causes most skin cancers. Sunscreen is one layer of protection, not a force field.
What people get wrong
Common beliefs about cancer, and what federal health agencies actually say about each one.
When short is not enough
These pages are the doorway, not the whole library. Each one links to longer articles at the bottom. If you would rather be guided, try a learning path. If you have just had a diagnosis, start at Just diagnosed. For prevention in more depth, see Prevention, and for myths in more depth, Cancer myths.
Children and teenagers have their own version of this, written to be read by them: Kids & Teens.