Cancer is common, but most people survive it
About 1 in 5 people in the United States will be diagnosed with cancer at some point in their life. That makes it common enough that most families know someone who has had it. But "common" does not mean "rare" is the opposite — it means cancer happens often enough that understanding your own risk and what to do if you get a diagnosis matters for almost everyone.
The chance that cancer will be diagnosed in you depends on your age, sex, family history, and lifestyle. A 25-year-old has a much lower risk than a 65-year-old. Someone who has never smoked has a lower risk than someone who has. These numbers shift based on who you are, which is why doctors talk about risk differently for different people rather than giving one number that applies to everyone.
Key Takeaways
- About 1 in 5 Americans will receive a cancer diagnosis in their lifetime, making it a common disease but not a certain one.
- Cancer risk increases with age — most diagnoses happen in people over 55, and the risk is much lower for younger adults.
- The five most common cancers in the United States are breast, lung, prostate, colorectal, and melanoma skin cancer.
- Survival rates have improved over the past 20 years for most cancer types, and many people live for years or decades after diagnosis.
- Your personal risk depends on age, sex, family history, smoking status, and other factors — not just the overall statistics.
How many people get cancer each year
In the United States, about 1.7 million new cancer diagnoses are made each year. That number has stayed roughly stable or risen slightly over the past decade, though the reasons are mixed — some cancers are becoming more common, while screening and detection have improved for others.
The number of new diagnoses varies by cancer type. Breast cancer is the most common, followed by prostate cancer in men, lung cancer, and colorectal cancer. Skin cancer (melanoma and non-melanoma types) is also very common, though it is often treated in an outpatient setting and may not be counted the same way as other cancers in national statistics.
These numbers come from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program, which tracks cancer diagnoses across the United States. The data lags by a year or two, so the most recent complete numbers available are usually from two years prior.
Cancer risk increases sharply with age
Cancer is primarily a disease of older adults. About 90 percent of cancer diagnoses occur in people age 55 and older. A 30-year-old has a much lower chance of a cancer diagnosis in the next year than a 70-year-old, even if both have similar risk factors.
This happens because cancer develops when cells accumulate damage over time. The longer you live, the more time cells have to develop the mutations that lead to cancer. This is why age is one of the strongest predictors of cancer risk, regardless of other factors.
For younger people, cancer is still possible but less common. In people under 40, cancers like testicular cancer, cervical cancer, and certain blood cancers are more likely than in older age groups. But overall, the number of young adults diagnosed with cancer each year is much smaller than the number of older adults.
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 cancer types over the past 20 years. For some cancers, the improvement has been dramatic. For example, the five-year survival rate for melanoma skin cancer has risen from about 80 percent in the 1980s to about 93 percent today.
Survival rates vary widely by cancer type and stage at diagnosis. Colorectal cancer caught early has a five-year survival rate above 90 percent, while pancreatic cancer (which is often found at a later stage) has a five-year survival rate around 10 percent. These numbers reflect both how treatable the cancer is and how early it is usually caught.
Survival rates also depend on age and overall health. A 40-year-old and an 80-year-old diagnosed with the same cancer may have different outcomes, partly because of age-related differences in how the body tolerates treatment and recovers from it.
Risk factors you can and cannot control
Some risk factors for cancer are fixed — you cannot change your age, sex, or family history. If your parent or sibling had cancer, your own risk may be higher, especially for breast, ovarian, and colorectal cancers. Certain genetic mutations, like BRCA1 and BRCA2, significantly increase the risk of breast and ovarian cancer.
Other risk factors are tied to choices and circumstances you may be able to change. Smoking is the single largest preventable cause of cancer. Alcohol use, obesity, physical inactivity, and sun exposure all increase cancer risk. Diet, workplace exposures, and infections (like human papillomavirus, or HPV) also play a role.
Having a risk factor does not mean you will get cancer. Many people who smoke never develop lung cancer. Many people with a family history of cancer never get diagnosed. Risk factors shift the odds, but they do not determine the outcome.
Screening can find some cancers early
For some cancers, screening — testing for the disease before symptoms appear — can find cancer at an earlier stage, when it is often easier to treat. Colonoscopy screens for colorectal cancer, mammography screens for breast cancer, and Pap tests screen for cervical cancer. These tests have reduced deaths from these cancers in people who get screened regularly.
Screening is most useful when the cancer is common enough to justify testing, when early detection actually improves outcomes, and when the test itself is reasonably safe and accurate. Not all cancers have effective screening tests. Pancreatic cancer, for example, does not have a screening test that doctors recommend for people at average risk.
Your doctor can discuss which screening tests make sense for you based on your age, sex, and risk factors. Screening recommendations change as new evidence emerges, so it is worth asking about current guidelines rather than assuming what you learned years ago still applies.
What "rare" and "common" mean for cancer
When doctors call a cancer "rare," they usually mean it accounts for less than 1 percent of all cancer diagnoses. Mesothelioma (cancer of the lining around the lungs, usually caused by asbestos exposure) is rare. So are certain childhood cancers and some blood cancers. Even rare cancers, though, affect thousands of people each year in the United States.
A "common" cancer like breast cancer accounts for about 15 percent of all new cancer diagnoses. But common does not mean it happens to most people — it means that among people who get cancer, breast cancer is the most likely type.
The distinction matters because rare cancers often have fewer treatment options and less research funding. Doctors may have less experience treating them. Support groups and information resources may be harder to find. But rarity does not determine how treatable a cancer is or what the outcome will be for an individual person.
Frequently Asked Questions
What is my personal risk of getting cancer?
Your personal risk depends on your age, sex, family history, and lifestyle factors like smoking and sun exposure. Your doctor can discuss your individual risk based on these factors. Online risk calculators exist for some cancers, like breast cancer, but they are most useful as a starting point for a conversation with your doctor rather than as a definitive answer.
If cancer runs in my family, will I definitely get it?
No. Having a family history of cancer increases your risk, but it does not may provide you will be diagnosed. Many people with a strong family history never develop cancer. Your doctor can discuss whether genetic testing or more frequent screening might be right for you.
Are cancer rates going up or down?
It depends on the cancer type. Lung cancer rates have fallen as smoking has become less common. Colorectal cancer rates have fallen due to screening. Melanoma rates have risen, partly due to increased sun exposure and better detection. Overall cancer rates have been relatively stable in recent years.
Can I reduce my cancer risk?
You can reduce your risk by not smoking, limiting alcohol, maintaining a healthy weight, staying physically active, protecting your skin from sun damage, and eating a diet high in vegetables and fruits. These changes lower your risk but do not eliminate it — cancer can occur even in people who do everything right.
What does a five-year survival rate actually mean?
It is the percentage of people diagnosed with a specific cancer who are still alive five years later. It does not mean people die after five years — many live much longer. It is a snapshot of outcomes at one point in time and varies based on stage at diagnosis, age, and other factors.