GoodRx Guide
Cancer
Comprehensive information for you or a loved one — including treatment options and discounts on popular medications.
But sometimes these DNA mutations allow the cell to bypass those safety checkpoints. And so it starts to grow and divide uncontrollably, and it becomes cancerous.
As the number of cells increases, they can grow into a tumor. And that tumor can start to invade surrounding tissues. This invasion is what makes a tumor malignant (cancerous) instead of benign (noncancerous).
Sometimes cells from the tumor can even break off and travel to other areas of the body. This is how cancer spreads — or becomes metastatic. Those traveling cancer cells can then set up shop in other organs and start to form new tumors. These are called metastasis.
What causes cancer?
There is no single thing that causes cancer. In some cases, it can start with a genetic predisposition. In other words, some people inherit genes from their parents that make them more likely to develop specific types of cancer.
But genetics are only part of the story. Life and the environments people live in come into play and can tip the scales. And, in many cases, these have a bigger role than any genetic risk.
The cancer risks people face throughout life include:
Aging
Radiation
UV (ultraviolet) rays from the sun
Smoking cigarettes
Alcohol
Viral infections, like HPV (human papillomavirus) or hepatitis C
The most common types of cancer
The most common types of cancer in the U.S. are:
Of these, lung cancer has the highest death rate. It accounts for 23% of cancer-related deaths in the U.S. Here are the other types of cancer that are most deadly:
Colon and rectal cancer (9% of cancer-related deaths)
Pancreatic cancer (8%)
Female breast cancer (7%)
Prostate cancer (5%)
Liver and bile duct cancer (5%)
Diagnosis
A cancer diagnosis is a different journey for everyone.
Screening tests can detect some cancers. These tests are designed to pick up on early signs of cancer — or precancer — before it becomes a bigger problem. Examples include:
Mammogram for breast cancer
Colonoscopy for colon cancer
Pap smear for cervical cancer
Prostate-specific antigen (PSA) test for prostate cancer
In some cases, testing for another condition reveals a sign of cancer before it starts to cause any symptoms. This can happen when a chest X-ray shows a spot that looks like it could be lung cancer. Or someone’s blood counts might show a sign of leukemia. And, of course, sometimes people develop new symptoms from cancer that lead to the diagnosis — like pain from a growing tumor, unexplained weight loss, or new jaundice.
Once a test result reveals a possible cancer, there are usually several more rounds of testing to figure out if it is cancer, what kind of cancer it is, and how far it has spread. This often requires:
More blood tests
CT scans or MRIs to get a closer look at the tumor
Biopsy of the tumor
Treatment
Cancer treatment is a big and rapidly changing world. Cancer specialists work closely with people to develop treatment plans that are highly individualized to the person and their cancer, other medical conditions, and personal preferences. So there’s a lot of variation in treatment from person to person.
Most people receive a combination of two or more of the following treatments:
Radiation: This treatment uses high-energy beams to destroy cancer cells. The radiation beams are directed at the tumor to avoid damage to the surrounding tissue.
Surgery: This is an option for some tumors. Sometimes removal happens after treatment with radiation or chemotherapy to shrink the tumor.
Chemotherapy: This refers to medications that are designed to kill cells that are rapidly dividing — like cancer cells. Unlike radiation or surgery, chemotherapy is delivered to the whole body. So it kills cancer cells wherever they may be.
Hormone and targeted therapy: These are medications that block cell receptors that help the cancer grow. In other words, they cut off the cancer’s food supply. For example, many breast cancers grow in response to estrogen. So some breast cancer medications block these estrogen receptors.
Immunotherapy: This includes some of the newest cancer treatments. These medications help your own immune system identify and kill the cancer cells. So they basically recruit and build your body’s anticancer army.
Prevention
Cancer is not always preventable. But there are still steps you can take to reduce your risk. Cancer prevention starts with proper screening, so that you can catch early signs of cancer before it starts.
Your primary care provider is a great first stop for this. They can help you understand which cancers you’re at risk for because of your age, ethnicity, or personal medical history. This also includes learning about cancers that run in your family.
Knowing your individual risk helps to pinpoint which cancer screening tests you need. There are many different cancer screening exams and tests out there. And some tests are recommended for everyone, like colonoscopies for colon cancer. Others are only necessary when someone has a higher risk, like lung CT scans for people with a smoking history.
But cancer prevention is not all about detection. There are also lifestyle changes you can make that will help reduce your risk. These vary for different types of cancer, but some of the common ones include:
Cutting back on smoking
Avoiding or reducing alcohol use
Following a diet that’s high in fruits, vegetables, and healthy proteins
Exercising regularly
Living with cancer
Living with cancer requires support across many different aspects of your life. And the best treatment plans go well beyond killing the cancer. They address the importance of social support and mental health, financial challenges, transportation, and home-care needs.
If you or someone you care about is living with cancer, it helps to reach out to the many support systems that can make it easier to get through the day. A few examples include:
Family and friends
Cancer support groups
Caregiver support groups
Therapists and mental health professionals
Social workers, who can help with things like financial concerns, transportation to and from appointments, and home healthcare
Many cancer treatment centers have a team of people ready to help you navigate the challenges throughout your journey.
Common concerns
Many times, cancer does not cause any symptoms in the early stages. This is why screening tests are so helpful. As cancers grow, they can start to cause many different types of symptoms (depending on the type).
Some common symptoms include:
Extreme fatigue or weakness
Complete loss of appetite or significant weight loss
New, unexplained pain that won’t go away
Abnormal bleeding, such as bruising, blood in the urine, or black stools
There’s no single “best” food group to prevent cancer. But your diet does make a difference.
Research suggests that plant-based foods seem to be most effective at lowering cancer risk. A plant-based diet is one that’s high in fruits, vegetables, beans, and whole grains. Other high-impact changes you can make include avoiding processed meat and lowering alcohol intake.
Many cancer specialists are hesitant to use the word “cure.” This is because even after treatment — when there are no longer any signs of cancer in the body — a small number of cancer cells may remain undetected. And these cells can lead to cancer recurrence in the future. This is where the idea of remission comes in.
When someone is in “complete remission,” it means there are no longer detectable signs of cancer in the body. People who are in remission often get yearly testing to look for any signs of recurrence. In some cases, a person is considered “cured” when they have been in complete remission for more than 5 years.
References
American Society of Clinical Oncology. (2021). Body weight and cancer risk.
Centers for Disease Control and Prevention. (2022). An update on cancer deaths in the United States.
National Cancer Institute. (2022). Cancer-causing substances in the environment.
National Cancer Institute. (2022). Common cancer types.
