Cancer is a large group of diseases with one thing in common: They happen when normal cells become
cancerous cells that multiply and spread. Your genes send instructions to your cells — like when to start
and stop growing, for example. Normal cells follow these instructions, but cancer cells
Cancer is the second most common cause of death in the U.S. But fewer people are
dying of cancer now than 20 years ago. Early detection and innovative treatments are
curing cancer and helping people with cancer live longer .
Types of cancer
There are over 100 types of cancer. Healthcare providers categorize them according to where
they start in your body and the type of tissue they affect. There are three broad cancer
classifications:
Solid cancers: This is the most common type of cancer, making up about 80% to 90% of all
cases. This includes carcinoma that forms in epithelial tissue (like your skin, breast, colon and
lungs) and sarcoma that forms in bone and connective tissues.
Blood cancers: These are cancers that start in your blood cells or lymphatic system. Examples
include leukemia, lymphoma and multiple myeloma.
Mixed: Cancers that involve two classifications or subtypes. Examples include carcinosarcoma
and adenosquamous carcinoma.
How common is cancer?
Cancer is the second most common cause of death worldwide. Researchers estimate that in
2024, over 2 million people living in the U.S. will receive a cancer diagnosis, and over 611,000
people will die from the disease.
About 1 in 4 people will develop cancer at some point during their lifetime.
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The most common cancers in the U.S. are:
Breast cancer .
Lung cancer .
Prostate cancer.
Colorectal cancer.
Blood cancers .
Anyone can develop cancer, but cases vary based on race and sex. According to the 2022 Annual
Report on Cancer, the disease:
, Affects slightly more men than women.
Affects people over 60 more than any other age group.
Affects more Black men than those in other racial groups.
Affects more women who are American Indian or Alaska Natives than those in other racial
groups.
Symptoms and Causes
What are the symptoms of cancer?
Symptoms of cancer vary from person to person. They depend on what type of cancer you have
and how advanced it is.
General cancer symptoms may include:
Fatigue .
Fever that occurs mostly at night.
Loss of appetite.
Night sweats.
Persistent pain.
Skin changes, particularly moles that change shape and size or new moles.
Unexplained weight loss .
In some cases, cancer may cause additional organ-specific symptoms. These may include:
Blood in your pee or in your stool.
Changes in the shape, color or size of a skin mole.
Coughing up blood .
New lumps or bumps.
This isn’t an exhaustive list. And having these symptoms doesn’t necessarily mean you have
cancer.
Cancer is a complicated disease. Different types cause different symptoms. It’s also possible to
have cancer for years without knowing it. Other times, it can cause obvious symptoms that get
worse very quickly.
A good rule of thumb is to let a healthcare provider know any time there’s a change in your body
that lasts for more than two weeks.
What causes cancer?
Cancer is a genetic disorder. But that doesn’t necessarily mean it’s inherited. It happens when
genes that manage cell activity mutate (change). They create abnormal cells that divide and
multiply, eventually disrupting how your body works.