Cancer: Frequently Asked Questions

What is cancer?

Your body is made up of tiny building blocks called cells. When these cells change and grow out of control, it's called cancer. The abnormal cells crowd out normal, healthy cells, making it hard for your body to work in the right way. Normal cells grow when your body needs them, and die when they are no longer needed. Cancer is made up of abnormal cells that grow even though your body doesn’t need them. In most types of cancer, the abnormal cells grow to form a lump or mass called a tumor.

What causes cancer?

Two types of factors contribute to the cause of cancer. One is a tendency or predisposition to develop cancer. The other is exposure to the triggers that start it off. Examples are cigarettes, environmental toxins, sun exposure, or liver damage.

Why do some people get cancer and not others?

Some cancers seem to be partly inherited. These include a type of eye cancer, and a small number of breast and ovarian cancers. But for most cancers, healthcare providers think that some people’s cells may be more likely to become cancer (malignant). These people may develop a cancer with relatively less exposure to a cancer trigger, such as cigarettes or the sun, than people whose cells have a higher threshold.

Do we get cancer from what we eat?

Certain eating patterns can increase or decrease your risk for cancer. The high-fat, low-fiber diet common in developed countries may play a role in about a third of all cancers. The American Cancer Society (ACS) recommends a healthy eating pattern than includes a variety of fruits and vegetables as well as whole grains. ACS recommends that people limit or not eat red and processed meat, sugar-sweetened drinks, highly processed foods, and alcohol. It's also important to stay at a healthy body weight. Ask your provider what a healthy weight is for you.

Are chemicals and pollutants causing cancer?

Exposure to specific chemicals or pollution can raise your risk for cancer. In some jobs, prolonged exposure to a few chemicals may cause certain kinds of cancers. Certain cancer-causing substances (carcinogens) have been identified and are regulated. The American Cancer Society has more information on chemicals, cancer risk, and how to limit your exposure.

Does smoking really cause cancer?

Yes. Cigarettes cause most cancers of the lung. They are a big factor in cancers of the bladder, pancreas, mouth, larynx, esophagus, and kidney. Smoking cigars is associated with risk of lung, oral, larynx, and esophageal cancer. There's also a link between secondhand smoke and cancer in both adults and children. The long-term health effects of e-cigarettes are still being studied.

Can cancer be prevented?

Healthcare providers think a lot of cancer can be prevented. Prevention methods include not smoking, preventing sun damage, practicing safe sexual behavior, and eating a healthy diet. These can reduce the incidence of cancer. Getting recommended cancer screenings can help find and treat pre-cancers and cancers early. Screenings may be done for cervical, breast, colorectal, and lung cancer. Ask your provider what screenings you may need. It's important to note that many people who get cancer don't have any known risk factors. But more could probably be prevented if more information was known, so research is very active in this field.

Why does the diagnosis seem to be so delayed in so many cases?

Cancer cells can multiply to produce literally billions of cells before a tumor becomes big enough to detect or cause symptoms. That is why prevention and some methods of screening are so important. Screening tests help find cancer before a person has symptoms.

Why isn’t there a simple, universal test for cancer?

Because cancer cells are very similar to normal cells, and a cancer begins with a very small number of cells. In a small number of cancers, certain tests can detect early changes. The best example is cancer of the cervix (the Pap test).

Also, cancer is not one disease but a category of diseases.  For example, breast cancer is much different from lung cancer, so tests to detect or diagnose it are different.

Why do people with the same cancer get different treatment and have different problems?

A lot depends on the stage of the disease and on the particular person. For instance, in breast cancer with involved lymph nodes, if you are postmenopausal, the best treatment may be a hormone tablet. If you are premenopausal, it may be chemotherapy.

Does conventional treatment work?

Surgery, chemotherapy, and radiation are examples of conventional cancer treatments. It's possible for some cancers to be cured. But the goal of cancer treatment is different for each person.. The goal may be to cure the cancer, control the cancer, or ease symptoms (palliation). Talk to your healthcare team about the goal of your cancer treatment so you know what to expect.

Does treatment cause side effects?

Many treatments are very well-tolerated. But treatment can cause side effects because cancer cells are very much like normal cells. So to kill cancer cells, you often risk damaging normal cells or tissues. This is different from other illnesses like bacterial infections for instance. Because bacteria are completely different from your body’s cells, antibiotics can kill them and not affect you very much.

Normal cells that are often damaged by cancer treatment include hair follicles, cells in the bone marrow that form new blood cells, and cells that line the mouth, digestive tract, and reproductive system. Damage to these cells cause side effects such as hair loss, fatigue, anemia, nausea, vomiting, diarrhea, and changes in sexual function and fertility. Your healthcare team can help you know what side effects to expect, when to report them, and how to manage them.

Can fatigue be prevented?

Fatigue can't be prevented because the exact cause of fatigue is not always known. But you can decrease the effect of fatigue, such as conserving energy. If your fatigue is related to low red blood cell count (anemia), there are ways to raise your level and relieve fatigue. See the information in the fatigue topic zone, and talk with your nurse or doctor so that he or she can help you to manage fatigue.

I am going to start radiation next week. What should I expect, and what can I do to decrease the fatigue?

Fatigue related to radiation treatments usually starts about the second or third week of treatment, and may continue for up to 3 months or longer afterward. It is important to take good care of yourself. This means eating a well-balanced diet, drinking lots of fluid, sleeping well at night, and doing exercise as tolerated, such as walking regularly. Once you start feeling fatigued, match your activity to how you feel. You should identify the activities or tasks that you have to do, and ask someone else to do the other tasks.

First, if you are driving yourself to your radiation treatments, see if someone else can drive you to your radiation treatments when you start feeling tired.

Second, try keeping a diary of how you feel, what makes you feel more energetic, what makes you feel more tired. Don't do the more tiring activities. Rate the activities using a simple scale, such as on a scale of 0 (full of energy) to 10 (absolutely exhausted, no energy).

Third, talk with your doctor or nurse about problems that arise, or if your fatigue is severe.

How does fatigue affect a person?

Fatigue is a real symptom. It can lead to a decrease in quality of life. Factors such as treatment, low red blood cell count (anemia), stress, problem sleeping, and poor nutrition can all add to fatigue. Still, since no one else can see your fatigue, it's common to question yourself about it. Don't. Fatigue is often a real part of cancer and its treatment. 

Fatigue affects each person differently. Plus, there are many degrees of fatigue. Some people may find that they are unable to do simple things that they used to do, such as climbing stairs without stopping or holding onto the handrail. Others may have trouble standing up in the shower, and get too tired, so a shower chair is helpful. Changes in mental processes can happen, causing “fuzzy thinking.” It may be hard to concentrate or focus on things, such as reading or watching television. Visiting with family, cooking, or other activities that you used to enjoy before starting cancer treatment may now be too exhausting. But there are tips to help conserve your energy for the activities that are important to you.

How can I ask my family to help me?

This may be one of the hardest things to do. Most family members want to help and are just waiting to do something. Often they feel helpless, and afraid to ask if they can help. By being very specific about what you would like them to do, it will make it much easier for them to help. Sometimes, a family meeting is a good way to tell family what is going on, and to organize the tasks and activities. A family meeting may also be helpful when family members may not understand that fatigue is a real problem related to cancer and its treatment. Your doctor, nurse, or a social worker can help with this, too.

When should I call my healthcare provider about my fatigue?

You should call your healthcare provider if any of these occur:

• Feel dizzy

• Lose your balance

• Have trouble sitting, standing, or walking

• Sleep all the time

• Can’t sleep at night

• Suddenly feel much more fatigued

• Hurt yourself

• Need help talking with your family about your feelings or needs

• Any new problem that you need help with

How can I get the best from my healthcare provider?

The key to getting the best from your medical team is to present your problems as clearly and accurately as you can. Make sure you clarify exactly what it is you want to know and what you need.

Can a change in diet alter the course of cancer?

Not as far as researchers know. Many cancer centers are currently involved in finding out whether a certain diet can alter the course of cancer in some selected early cases. But there is no evidence that diet supplements, vitamins, minerals, or special diets actually change the course of a cancer once it has developed.

With so many advances, why isn't there more progress?

Researchers have made tremendous—and increasing—progress in their understanding of cancer, but the gap between understanding and treatment (between lab and bedside) is a wide one. Because stories about cancer research are often reported in the media as if that gap were small, people tend to expect big changes in treatment. This tendency is partly responsible for the widespread feeling of disappointment with the impact of cancer research.

Will there ever be a cure for cancer?

Many cancers ARE cured. Since every cancer is different, finding a single universal cure is unlikely. This is similar to there not being a single antibiotic that cures all infections. It's quite likely that researchers will make further advances in some cancers. The biggest changes in cancer may come from prevention or from other directions, such as treatments or vaccines to prevent spread after the primary cancer has been removed. Obviously nobody knows what is going to happen, but a single, sudden breakthrough that produces a universal miracle cure is very unlikely.

Will my hair grow back?

Yes, hair loss from chemotherapy is temporary. It will grow back, usually after therapy is finished. In some cases, hair can grow back during therapy. Usually the texture of the hair is different for the first year. Then, after a year or so, it usually goes back to how it was before you took chemotherapy. Hair loss from radiation therapy may be irreversible.

If I have a lot of side effects, does that mean the chemotherapy is working?

The side effects occur because the chemotherapy hurts normal cells that divide often, as well as the cancer cells. There is much that can be done to prevent or lessen the side effects that a person gets after chemotherapy.

Are the side effects of chemotherapy worse than the cancer?

Nausea and vomiting are are the worst of the side effects for many people. These often can be controlled. Fatigue is finally getting the attention it deserves, and there are many self-care tips that can help. Anemia, which can cause fatigue, can also be prevented or treated in many cases.

Does everyone with cancer get anemia?

No. Anemia is a common condition that can be caused by non-cancer (benign) conditions. Some cancers can suppress the body's ability to make blood normally. Some cancer treatments can cause anemia. Many cancer patients will never have anemia; and many people without cancer can develop anemia for other reasons.

What effect does alcohol have on anemia?

Anemia has many different types and causes. Alcohol can cause anemia by suppressing the body's ability to make blood normally. Alcohol use can also lead to conditions that increase the risk of bleeding, poor nutrition, and chronic disease that leads to anemia. If you have questions about using alcohol during cancer treatment, talk with your healthcare provider.

Why don’t I get anemia right after my chemotherapy?

The red blood cells in the body live for about 120 days, or 3 months. Chemotherapy doesn’t hurt the red blood cells that are already made and circulating in the blood. Chemotherapy injures the cells in the bone marrow that make the red blood cells. The chemotherapy prevents these cells from replacing the normal red blood cells when they are used up. That is why the anemia may not develop for a while after the chemotherapy starts.

How is anemia treated?

Treatment depends on the cause of the anemia. If the anemia is caused by not enough building blocks in the body (like iron, folic acid, or vitamin B12), the treatment includes adding these back to the body. Red blood cells can then be made, and the blood values return to normal. If the cause is chemotherapy, or sometimes radiation, then red blood cell transfusions or injections of erythropoietin can be given in some cases. Erythropoietin is a natural hormone made by the kidneys. It tells the bone marrow to make more red blood cells.

Should everyone get a second opinion?

Many people with cancer get a second opinion from another doctor. There are many reasons to get a second opinion, including if you are not comfortable with the treatment decision, if the type of cancer is rare, if there are different ways to treat the cancer, or if you are not able to see a cancer expert. Also, some health insurance companies require a second opinion before treatment begins. A second opinion can help you have more confidence in the cancer diagnosis, treatment plan, or treatment team.

How can someone get a second opinion?

You can get a second opinion in many ways:

• Your primary doctor may be able to recommend a specialist, such as a surgeon, medical oncologist, or radiation oncologist. Sometimes these doctors work together at cancer centers or programs.

• You can call the Cancer Information Service at 800-4-CANCER (800-422-6237). This service informs callers about treatment facilities, including cancer centers and other programs supported by the National Cancer Institute.

• You can get names of doctors from your local medical society, a nearby hospital, a medical school, or local cancer advocacy groups, as well as from other people who have had that type of cancer.