Doctor and patient facing each other while doctor explains test resultsCancer refers to any one of the many related diseases that spread throughout cells in the body. There are more than 100 types of cancer. Some form tumors, while others might affect blood cells instead. Certain types of cancer may not be easy to treat, but many types of cancer are highly treatable. Some people with cancer even experience complete remission (where there is no longer any sign of cancer in the body).

If you or a loved one has been diagnosed with cancer, you may be anxious, worried, and overwhelmed. If you are taking medication or beginning chemotherapy, you might also be experiencing side effects or feeling unwell. It can be difficult, even exhausting, to process a diagnosis, but therapy can help.

Your doctor may encourage you to reach out to a social worker, therapist, or counselor, and this might be helpful for you. In therapy, you can process your feelings, explore ways to share your diagnosis with friends and family, and discuss concerns you have about the ways cancer might change your life. Some therapists are even specially trained in working with people who have cancer. GoodTherapy can help you find a counselor.

Cancer Statistics

More than 38% of the U.S. population will be diagnosed with cancer in their lifetime. Doctors are expected to diagnose more than 1.7 million new cases of cancer in 2018.

In the United States, about 163 of every 100,000 people die from cancer each year. It’s estimated that more than 600,000 people living in the U.S. will die from cancer in 2018.

Cancer is a leading cause of death worldwide. More than 14 million new cancer cases were diagnosed in 2012, and there were more than 8 million cancer-related deaths. By 2030, the number of new cancer cases diagnosed in the world each year is likely to surpass 23 million, according to experts.

There are 15.5 million cancer survivors in the United States, and the number of survivors is likely to pass 20 million by 2026. The overall cancer death rate is also declining. Between 2006 and 2015, deaths decreased among men by 1.8% and among women by 1.4%. Between 2011 and 2015, deaths decreased among children 19 and under by 1.4%.

Cancer Causes

Many people wonder what causes cancer. This question has many answers, and not all of them are backed by medical research. Reading up on the latest health news can be a good way to stay informed, but it’s a good idea to make sure any information is objective and backed by medical research. It’s also often helpful to look at the information in context.

Experts and medical researchers have studied cancer extensively and identified many substances (called carcinogens) that can lead to cancer. But not everyone exposed to these carcinogens will get cancer. Other factors, such as rate or frequency of exposure, may play a part.

Some of the more common known carcinogens include:

  • Alcohol
  • Asbestos
  • Benzene
  • Indoor coal emissions
  • Diesel exhaust
  • Formaldehyde
  • Leather dust
  • Processed meat
  • UV radiation
  • Tobacco (smoked or chewed)
  • Wood dust

Certain viruses, such as HPV or hepatitis, can increase cancer risk.

Some people have genes that increase their risk for cancer. For example, hereditary breast cancer is most often caused by a gene mutation. This mutation greatly increases the risk of developing cancer.

Other risk factors for cancer include poor diet and nutrition, alcohol overuse, inactivity, and obesity. According to the World Cancer Research Fund, about 20% of cancer diagnoses in the U.S. relate to these risk factors. Some people live in circumstances that make it difficult or impossible to reduce cancer risk factors, but it is generally possible to reduce cancer risk.

Cancer Types

There are more than 100 different cancer types. Cancer can develop in any part of the body, and cancers are often named after the part of the body they form in. Breast cancer affects cells in the breast, for example, while lung cancer develops in lung cells. Some cancers might be named after the cells that create them. Cancers often cause tumors to develop. Cancers such as leukemia affect the blood, and other cancers, such as osteosarcoma, affect the bones.

Among the most common types of cancer are:

  • Breast cancer
  • Lung cancer
  • Prostate cancer
  • Colorectal cancers
  • Melanoma
  • Bladder cancer
  • Pancreatic cancer
  • Non-Hodgkin lymphoma
  • Prostate cancer
  • Thyroid cancer

The American Cancer Society compiled the above list by determining the expected number of new cases in 2018 for each of these types of cancer. Breast cancer, with an estimate of 268,670 new cases, was the most common cancer. Lung cancer is the next most common.

Certain types of cancer are more likely to affect different age groups. For example, children under the age of 14 are most likely to be diagnosed with leukemia, lymphomas, or brain or central nervous system tumors. Young adults are more likely to be diagnosed with sarcomas or Hodgkin lymphoma, but leukemia is also common in teens and young adults. Some cancers, such as testicular or ovarian cancer, are specific to sex assigned at birth.

Cancer is a serious health concern. Some types of cancer may be fatal, but many types of cancer are treatable. Cancer treatment depends on the type of cancer someone has and the cancer stage, which describes how much the cancer has spread throughout the body. Doctors work with the people they treat to determine the best approach for the type of cancer they have.

Treatment might include surgery, immunotherapy, transplants, chemotherapy, or radiation therapy. Cancer treatment is most effective in the early stages of cancer. It’s important for people experiencing certain symptoms to see a doctor right away.

Cancer Symptoms

There are many symptoms of cancer, and they usually depend on where the cancer is. Signs of cancer can also indicate any number of other health conditions. It’s important to discuss any strange or worrisome symptoms with a doctor right away.

Common symptoms of cancer include:

  • Fatigue or general weakness
  • Unexplained weight loss or weight gain
  • A cough that doesn’t go away
  • Breathing problems
  • Bruising
  • Unexplained pain in the muscles or joints
  • Changes to skin color
  • Changes in moles, new moles
  • Lumps under the skin
  • Unexplained or unusual bleeding

If symptoms persist for more than a week or two, it may be wise to see a doctor. Symptoms may not be due to cancer, but if they are, early treatment is often most successful.

Cancer Prevention

There is no cure for cancer, and there is no vaccine that prevents all cancers. But there are currently two FDA-approved cancer prevention vaccines. They help protect against specific types of cancer.

  • The HPV (human papillomavirus) vaccine can help prevent cervical and anal cancers, as well as genital warts. Since the HPV vaccine was first recommended for teenage girls in the U.S., HPV infection has declined by about 64%.
  • The hepatitis B vaccine protects against the hepatitis B virus, which can lead to liver cancer.

A person’s risk for cancer depends on many factors. These include genetics, lifestyle, and environmental factors. Some risk factors cannot be changed. However, there are steps people can take to reduce the risk of developing cancer.

  1. Avoid known carcinogens. Some common carcinogens that are often easily avoided include alcohol, cigarette smoke, and UV rays. It’s recommended that men have no more than two drinks per day and women have no more than one drink per day.
  2. Be active. Getting enough physical activity can help reduce cancer risk. A study looking at 1.44 million people from the U.S and Europe found that people who spent leisure time being physically active had a lower risk for 13 cancers.
  3. Choose nutritious foods. Eating plenty of fresh fruits and vegetables, avoiding processed foods or foods high in sugar and fat, choosing whole grains, and limiting red meats can help reduce cancer risk by promoting whole-body health as well as a healthy weight. Foods believed to help lower cancer risk include broccoli, carrots, beans, berries, and nuts.

Cancer Month

In the United States, many different cancer awareness campaigns are recognized throughout the year. These are often referred to as cancer awareness months, or simply cancer months. People might wear a cancer ribbon to represent their (or a loved one’s) battle with cancer.

These campaigns include (but are not limited to):

  • National Cancer Prevention Month (February)
  • National Colorectal Cancer Awareness Month (March)
  • National Cancer Control Month, Testicular Cancer Awareness Month (April)
  • National Minority Cancer Awareness Week (second week of April)
  • Bladder Cancer Awareness Month, Cancer Research Month, Melanoma/Skin Cancer Detection and Prevention Month (May)
  • Sarcoma Awareness Month (July)
  • Childhood Cancer Awareness Month, Gynecologic Cancer Awareness Month, Blood Cancer/Leukemia and Lymphoma Awareness Month, National Ovarian Cancer Awareness Month (September)
  • National Breast Cancer Awareness Month (October), National Liver Cancer Awareness Month (October)
  • Lung Cancer Awareness Month, Pancreatic Cancer Awareness Month (November)


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