Cancer is common, but most people do not get it in any given year
About 1 in 5 Americans will be diagnosed with cancer at some point in their lifetime. That sounds high until you remember that "lifetime" means from birth to age 85 or older. In any single year, fewer than 1 in 100 Americans receive a new cancer diagnosis. The chance depends heavily on age — it rises sharply after 50 — and on factors like smoking history, family history, and where you live.
The most common cancers in the United States are breast cancer, lung cancer, prostate cancer, and colorectal cancer. These four account for roughly half of all new diagnoses. Skin cancer is even more common but is often not counted in these statistics because most skin cancers are caught early and have high survival rates.
Key Takeaways
- About 1 in 5 Americans will receive a cancer diagnosis in their lifetime, but this spans many decades and includes people of all ages.
- Cancer risk increases significantly after age 50, so most diagnoses occur in older adults.
- Breast, lung, prostate, and colorectal cancers together make up roughly half of all new cases.
- Survival rates have improved over the past 20 years for most cancer types, especially when caught early.
- Your personal risk depends on age, family history, smoking status, and other factors specific to you.
Why cancer becomes more common with age
Cancer develops when cells in the body start to grow in an uncontrolled way. This usually happens because of damage to the DNA inside cells — the instruction manual that tells cells how to behave. This damage builds up over time, which is why cancer is much rarer in children and young adults than in older people.
A 30-year-old has had fewer years for this damage to accumulate. A 70-year-old has had four decades more. This is why the risk of cancer roughly doubles every 10 years after age 50. It is not that something changes about aging itself — it is simply that more time has passed for the damage to occur.
How many people are living with cancer right now
About 18 million Americans are alive today who have had a cancer diagnosis at some point. This includes people currently undergoing treatment, people in remission (meaning their cancer is not detectable), and people who were treated years ago and have not had a recurrence. The number keeps growing because more people are being diagnosed and more people are surviving longer after diagnosis.
This is different from the number of new diagnoses each year. In the United States, roughly 1.7 to 1.9 million new cancer cases are diagnosed annually, though this number varies slightly from year to year. The variation depends on screening rates, population changes, and whether new cases of skin cancer are included in the count.
Which cancers are most common and least common
Breast cancer is the most commonly diagnosed cancer in the United States, followed by prostate cancer in men and lung cancer in both men and women. Colorectal cancer ranks fourth. These four cancers together account for about 50% of all new diagnoses.
Less common cancers include pancreatic cancer, ovarian cancer, and mesothelioma (a cancer linked to asbestos exposure). Some cancers are so rare that fewer than 1,000 people in the entire country are diagnosed with them each year. Rarity does not mean the cancer is less serious — some of the rarest cancers are among the hardest to treat.
| Cancer Type | Approximate New Cases Per Year (US) | More Common In |
|---|---|---|
| Breast cancer | 290,000 | Women (though men can get it) |
| Prostate cancer | 290,000 | Men |
| Lung cancer | 235,000 | Current or former smokers; both sexes |
| Colorectal cancer | 150,000 | People over 50 |
| Melanoma (skin) | 100,000 | People with fair skin and sun exposure |
Survival rates have improved for most cancers
The five-year survival rate — the percentage of people still alive five years after diagnosis — has improved for most cancers over the past two decades. For breast cancer, the five-year survival rate is now about 90%. For prostate cancer, it is about 98%. For colorectal cancer, it is about 65%.
These numbers vary depending on how early the cancer is caught. A cancer found at stage 1 (before it has spread) usually has a much better survival rate than the same cancer found at stage 4 (after it has spread to other parts of the body). This is why screening programs for breast, prostate, and colorectal cancer exist — catching cancer early makes treatment more likely to work.
What affects your personal cancer risk
Your age is the strongest predictor of cancer risk, but it is not the only one. Smoking is the single largest preventable cause of cancer. Family history matters — if a close relative was diagnosed with cancer, your risk may be higher. Obesity, heavy alcohol use, and sun exposure also increase risk for certain cancers.
Some people inherit genetic mutations that make cancer more likely. The most well-known are mutations in the BRCA1 and BRCA2 genes, which increase the risk of breast and ovarian cancer. A genetic counselor or your doctor can help you understand whether your family history suggests you should be tested for these mutations.
Where you live can also matter. Exposure to radon (a radioactive gas that seeps into some homes), air pollution, and contaminated water can increase cancer risk. Your occupation may expose you to cancer-causing substances. None of these factors guarantees you will get cancer, but they shift the odds.
How screening programs work and who should use them
Screening means testing for cancer before you have symptoms. The goal is to find cancer early, when treatment is more likely to work. Screening programs exist for breast cancer (mammography), colorectal cancer (colonoscopy or other tests), and cervical cancer (Pap smear). Prostate cancer screening with a blood test called PSA is available but more controversial because it can lead to treatment of cancers that would never have caused harm.
Different organizations recommend screening at different ages. The American Cancer Society recommends that women begin mammography at age 40 or 45 and that adults begin colorectal cancer screening at age 45. Your doctor may recommend earlier screening if you have a family history of cancer or other risk factors. Screening is not right for everyone — your doctor can help you decide whether it makes sense for you.
Frequently Asked Questions
Is cancer more common now than it used to be?
The number of new cancer cases has risen over the past 30 years, but much of this is because the population is older and larger. When adjusted for age, cancer rates have actually been relatively stable or declining slightly for many cancer types. Improved screening and detection also mean more cancers are found that might have gone unnoticed before.
If cancer runs in my family, will I definitely get it?
No. Family history increases your risk, but it does not determine your fate. Many people with a family history of cancer never develop it. A genetic counselor can help you understand your actual risk based on which relatives were affected, at what age, and what type of cancer they had.
What is the difference between incidence and mortality?
Incidence is the number of new cancer cases diagnosed. Mortality is the number of people who die from cancer. These numbers are different because many people survive cancer. Mortality rates have fallen for most cancers even as incidence has stayed relatively stable, meaning more people are living longer after diagnosis.
Can I reduce my cancer risk?
You cannot eliminate cancer risk, but you can lower it. Not smoking, limiting alcohol, maintaining a healthy weight, exercising regularly, eating a diet rich in vegetables, and protecting your skin from sun damage all reduce risk for multiple cancer types. Regular screening (if recommended for your age and risk factors) also catches cancer earlier, when it is easier to treat.
Why do some cancers have better survival rates than others?
Survival depends on how fast the cancer grows, how early it is usually caught, and how well current treatments work against it. Breast cancer has a high survival rate partly because screening catches many cases early. Pancreatic cancer has a lower survival rate because it often grows quickly and is usually found at a later stage.