Questions & Answers

Short, plain-language answers to common questions — every answer is based on a National Cancer Institute resource, with a link to the original.

• Are all brain tumors cancer?No. Brain and spinal cord tumors can be benign (not cancer) or malignant (cancer).
• Are pancreatic neuroendocrine tumors different from other pancreatic cancer?Pancreatic neuroendocrine tumors are less common than the exocrine type of pancreatic cancer, but they have a better prognosis.
• Are placebos used in cancer clinical trials?Placebos are rarely used in cancer treatment trials, and if they are used, you will always be told ahead of time.
• Are thyroid nodules cancer?Thyroid nodules are common but usually are not cancer; only a small number are diagnosed as cancer.
• Can a blood test diagnose cancer?Blood and other lab tests can point to cancer, but they cannot confirm it on their own; a biopsy is often needed to be certain.
• Can a cancer screening test be wrong?Yes. Screening tests can give false-positive results (showing cancer when there is none) and false-negative results (showing no cancer when there is).
• Can a tumor marker test alone diagnose cancer?A tumor marker test is usually not enough on its own—results are combined with other tests like biopsies or imaging to diagnose cancer.
• Can colorectal cancer be prevented?Colorectal cancer often begins as a polyp, and finding and removing polyps can prevent colorectal cancer.
• Can Hodgkin lymphoma be cured?Hodgkin lymphoma can often be cured, according to the National Cancer Institute.
• Can I get palliative care while still in cancer treatment?Yes. Palliative care can be given along with cancer treatment at any point from diagnosis onward.
• Can lymphedema be prevented after cancer treatment?There is no way to fully prevent lymphedema, but steps like protecting your skin and exercising can lower your risk or keep it from worsening.
• Can men get breast cancer?Yes. Breast cancer mostly affects women aged 45 and older, but anyone with breasts can get it, though it is rare in men.
• Can metastatic cancer be treated?There are treatments for most types of metastatic cancer, often aimed at controlling its growth and relieving symptoms.
• Can nausea and vomiting from chemotherapy be prevented?Yes—antinausea medicines often prevent or relieve nausea and vomiting, and they work best when taken before treatment.
• Can you gain weight during cancer treatment?Yes—some people gain weight during treatment, more often with ovarian, breast, or prostate cancer, or from steroids and hormone therapy.
• Can you get cancer even with no known risk factors?Yes. Cancer can develop in people who have no known risk factors, and having risk factors does not mean a person will get cancer.
• Can you leave hospice if you get better?Yes—you always have the option to stop hospice care, and patients may be discharged from hospice if their condition improves or they resume cancer treatment.
• Do I need testing before targeted therapy?Often yes; most of the time your tumor is tested (biomarker testing) to see if it has a target for a drug.
• Do most people need more than one cancer treatment?Most people with cancer have a combination of treatments, though some people have only one.
• Do side effects mean chemotherapy is working?No. Side effects have nothing to do with how well chemotherapy is fighting your cancer.
• Do vitamins and supplements prevent cancer?There is not enough proof that vitamins or dietary supplements can prevent cancer, and in one trial vitamin E alone increased prostate cancer risk.
• Do you need to have cancer to join a clinical trial?Not always. Most cancer trials involve people who have cancer, but prevention and screening trials may involve people at high risk or healthy volunteers.
• Does a positive attitude cure cancer?There is no convincing scientific evidence that a person's attitude changes their risk of getting or surviving cancer.
• Does cancer always cause pain?No. Cancer often does not cause pain, which is why you should not wait to feel pain before seeing a doctor about lasting symptoms.
• Does cancer fatigue go away after treatment ends?Fatigue usually decreases after cancer treatment ends, but some people still feel it for months or years.
• Does cancer treatment always cause hair loss?No—only some chemotherapy causes hair loss, and radiation causes it only in the treated area, so ask your team about your treatment.
• Does chemo neuropathy go away?The National Cancer Institute does not give a single answer on how long treatment-related neuropathy lasts—it recommends reporting symptoms early and asking your care team how long they might last.
• Does chemotherapy always cause hair loss?Chemotherapy can cause hair loss, but it does not always, and side effects often improve after treatment ends.
• Does everyone get the same side effects from cancer treatment?No—side effects vary from person to person, even among people receiving the same type of cancer treatment.
• Does family history affect ovarian cancer risk?Yes. A family history of ovarian cancer raises the risk, and about 20% of ovarian cancers are hereditary.
• Does having a risk factor mean I will get cancer?No. A risk factor raises the chance of developing cancer, but it does not mean cancer is certain.
• Does palliative care mean giving up?No—palliative care can be given alongside cancer treatment at any point from diagnosis onward, and research shows it can improve quality of life and mood.
• Does prostate cancer grow slowly?Prostate cancer usually grows very slowly, which is why finding and treating it early does not always help a man live longer.
• Does sugar feed cancer?No—eating sugar has not been shown to make cancer worse, and cutting out sugar has not been shown to make cancer shrink or disappear.
• Does sunlight cause melanoma?UV radiation from the sun, sunlamps, and tanning booths causes damage that can lead to skin cancer, and melanoma is one type of skin cancer.
• Does the machine touch me during external beam radiation?During external beam radiation, the machine does not touch you, though it can move around you.
• How can caregivers take care of themselves?Make time for yourself each day, keep up your routine, connect with others, and protect your own health so you have strength to care for others.
• How can I cope with fear and worry about cancer?Being informed often helps most—learning the facts about your cancer and treatment can reduce fear and help you know what to expect.
• How can I eat when I have no appetite during cancer treatment?Eat small high-protein, high-calorie meals every 2 to 3 hours, and use smoothies or supplement drinks when solid food is hard.
• How can I help someone with cancer?Caregiving can mean daily tasks, medical help, coordinating care, or emotional support—and every situation is different.
• How can I manage a dry mouth during cancer treatment?Sipping water often, sucking on ice chips or sugar-free candy, using lip balm, and asking about saliva substitutes can help with dry mouth.
• How can I manage memory problems during cancer treatment?Planning your day, exercising your body and mind, and using memory aids can help manage minor memory and concentration problems.
• How can I organize important papers for my family?Organizing records, listing where papers are kept, keeping originals safe, and giving family photocopies can help ease burdens on loved ones later.
• How can I prevent falls with nerve problems from cancer treatment?Making your home safer, wearing sturdy shoes, and getting up slowly can help prevent falls when nerve problems affect balance.
• How can I prevent infection during cancer treatment?Washing your hands often, staying extra clean, and avoiding germs are key ways to help prevent infection during cancer treatment.
• How can I relieve dry, itchy skin during cancer treatment?Gentle care such as recommended moisturizers, lukewarm showers, and avoiding alcohol or fragrance products may help relieve dry, itchy skin during cancer treatment.
• How can I stay safe with numb hands and feet?The National Cancer Institute lists safety steps you may be advised to take with nerve changes, such as preventing falls, taking care in the kitchen and shower, and protecting your hands and feet.
• How do I ask others for help as a cancer caregiver?Take an honest look at what you can and can't do, and share tasks like cooking, childcare, or driving—getting help also helps your loved one.
• How do I cope with the fear that my cancer will come back?Fear of recurrence is normal and often lessens over time; talking with your team, tracking symptoms, and a follow-up plan can help.
• How do I talk to my teenager about my cancer?Encourage teens to share their feelings and ask questions, tell them as much as they want to know, and let them talk with trusted people.
• How do scientists find cancer risk factors?Most risk factors are first identified in studies that compare large groups of people who develop cancer with those who do not.
• How does radiation therapy work?Radiation therapy kills cancer cells or slows their growth by damaging their DNA.
• How does surgery treat cancer?Surgery treats cancer by removing it from the body; it can remove a whole tumor, part of one, or ease symptoms.
• How is hormone therapy given?Hormone therapy may be given as pills, as injections, or through surgery to remove hormone-producing organs.
• How is immunotherapy given?Immunotherapy may be given by IV, by mouth, as a cream on the skin, or directly into the bladder, depending on the type.
• How is targeted therapy different from chemotherapy?Targeted therapy interferes with specific proteins that help tumors grow, while chemotherapy often kills all fast-dividing cells.
• How long does a pathology report take?A pathologist typically sends a pathology report to the doctor within 10 days after the biopsy or surgery.
• How long does a stem cell transplant take?A stem cell transplant can take a few months to complete, and immune recovery takes even longer.
• How long does chemo brain last?The National Cancer Institute does not give a set timeline for chemo brain—it recommends asking your health care team when problems might start and how long they might last.
• How long does chemotherapy last?Chemotherapy schedules vary widely and are often given in cycles of treatment followed by rest.
• How long does it take for hair to grow back after chemotherapy?After chemotherapy, hair often grows back in 2 to 3 months; after radiation therapy, in 3 to 6 months.
• How many people are diagnosed with cancer each year in the US?In 2025, an estimated 2,041,910 new cancer cases were expected to be diagnosed in the United States.
• How many types of cancer are there?There are more than 100 types of cancer, usually named for the organ or type of cell where they start.
• How many types of cancer treatment are there?There are many types of cancer treatment, including surgery, chemotherapy, radiation therapy, immunotherapy, targeted therapy, hormone therapy, and stem cell transplants.
• Is cancer a genetic disease?Yes. Cancer is caused by changes to the genes that control how cells grow and divide, though these changes are not always inherited.
• Is cancer contagious?In general, no—cancer is not a contagious disease and does not spread from person to person like a cold or the flu.
• Is cancer that spread to the liver the same as liver cancer?No. Cancer that starts elsewhere and spreads to the liver is not called primary liver cancer.
• Is chemo brain real?Yes—the National Cancer Institute describes memory and concentration problems, sometimes called chemo brain, as a known side effect of cancer treatment.
• Is it normal to feel depressed after a cancer diagnosis?Sadness is a normal response, but depression is a treatable medical condition—see your doctor if signs last more than two weeks.
• Is it safe to take a laxative during cancer treatment?During cancer treatment, use only laxatives your doctor recommends, and avoid suppositories and enemas unless prescribed.
• Is leukemia a childhood cancer?Leukemia is the most common cancer in children under 15, but it happens most often in adults older than 55.
• Is lung cancer only caused by smoking?No. Smoking causes most lung cancers, but people who have never smoked can also develop lung cancer.
• Is melanoma the most dangerous skin cancer?Melanoma is less common than other skin cancers but much more likely to spread, and most deaths from skin cancer are caused by melanoma.
• Is palliative care the same as hospice?No. Palliative care can begin at any point during cancer treatment, while hospice begins when the sole focus is quality of life rather than cure.
• Is prostate cancer common?Prostate cancer is the most common cancer among men in the United States and the second leading cause of cancer death among men.
• Is the cancer death rate going down?Yes. In the United States, the overall cancer death rate has declined since the early 1990s.
• Should I tell my young children I have cancer?Being honest is better than pretending, because even very young children can sense when something is wrong.
• Should I wait until my pain is bad before taking pain medicine?No—take pain medicine on schedule; the best way to control pain is to stop it from starting or getting worse.
• What are advance directives?Advance directives are legal papers that tell your loved ones and doctors what to do for you if you can't tell them yourself.
• What are common signs of endometrial cancer?Signs of endometrial cancer include unusual vaginal bleeding or pain in the pelvis.
• What are good bedtime habits during cancer treatment?Good bedtime habits during cancer treatment include going to bed only when sleepy, keeping the room quiet and dark, and avoiding screens and heavy meals before bed.
• What are signs of renal cell (kidney) cancer?Signs of renal cell cancer include blood in the urine and a lump in the abdomen.
• What are the benefits of joining a clinical trial?Possible benefits include helping future patients, access to a treatment under study, and close monitoring by the research team.
• What are the early signs of lymphedema?Early signs of lymphedema can include a heavy, full, or tight feeling, swelling, and numbness or tingling in the affected area.
• What are the four types of thyroid cancer?Thyroid cancer can be described as differentiated thyroid cancer (papillary, follicular, and anaplastic) or medullary thyroid cancer.
• What are the main risk factors for cancer?The most-studied risk factors include age, alcohol, tobacco, sunlight, radiation, obesity, diet, and several others.
• What are the main risk factors for head and neck cancer?Tobacco use, heavy alcohol use, and infection with certain types of HPV are key risk factors.
• What are the main types of cervical cancer?The two main types of cervical cancer are squamous cell carcinoma and adenocarcinoma.
• What are the main types of kidney cancer?The main types of kidney cancer are renal cell cancer, transitional cell cancer, and Wilms tumor.
• What are the side effects of cancer treatment?Side effects are problems that occur when cancer treatment affects healthy tissues or organs, and they vary from person to person.
• What are the side effects of hormone therapy?Side effects depend on the type of therapy and can differ for men and women, and often include hot flashes and fatigue.
• What are the signs of anemia in people with cancer?Anemia can make you feel very tired, short of breath, or lightheaded, with signs like dizziness, headaches, a fast heartbeat, and pale skin.
• What are the signs of caregiver stress?Caregiver stress can cause fatigue, sleep problems, higher blood pressure, appetite or mood changes—see your doctor if changes last over two weeks.
• What are the symptoms of peripheral neuropathy from chemotherapy?Symptoms depend on the nerves affected and may include tingling or numbness, muscle weakness, or changes in digestion and blood pressure.
• What are the two main types of lung cancer?The two main types of lung cancer are non-small cell lung cancer and small cell lung cancer.
• What are the two most common types of esophageal cancer?The two most common types are squamous cell carcinoma and adenocarcinoma.
• What are the two types of cells pancreatic cancer starts in?Pancreatic cancer can start in two kinds of cells in the pancreas: exocrine cells and neuroendocrine cells, such as islet cells.
• What are the two types of uterine cancer?The two types of uterine cancer are endometrial cancer, which is common, and uterine sarcoma, which is rare.
• What are the types of cancer clinical trials?The main types are treatment, prevention, screening, and supportive or palliative care trials, each answering a different research question.
• What are the types of leukemia?Leukemia has several types, including acute and chronic forms defined by the blood cell involved and how fast the cancer grows.
• What are the types of radiation therapy?The two main types are external beam radiation and internal radiation, which can use a solid or liquid source.
• What can I do about taste changes during cancer treatment?Marinades, herbs, tart flavors, and non-metal utensils can help when cancer treatment changes how food tastes; changes often improve after treatment.
• What cancers does hormone therapy treat?Hormone therapy is used to treat prostate and breast cancers that use hormones to grow.
• What causes almost all cervical cancers?Long-lasting infection with HPV (human papillomavirus) causes almost all cervical cancers.
• What causes anemia during cancer treatment?Cancer treatments like chemotherapy and radiation, and cancers that affect the bone marrow, can lower red blood cells and cause anemia.
• What do positive and negative margins mean on a pathology report?A negative (clean) margin means no cancer cells at the edge of removed tissue; a positive (involved) margin means cancer cells were found there.
• What does cancer prevention mean?Cancer prevention is action taken to lower the chance of getting cancer, such as avoiding known causes and making healthy lifestyle changes.
• What does central nervous system tumor mean?A central nervous system (CNS) tumor is a tumor of the brain or spinal cord.
• What does it mean to be a cancer survivor?A person is a cancer survivor from the time of diagnosis through the rest of life, including those living with cancer and those free of it.
• What does the stage of a cancer mean?The stage describes the extent of a cancer—how large the tumor is and whether it has spread—and helps doctors plan treatment.
• What does TNM staging mean?In the TNM system, T describes the main tumor, N describes nearby lymph nodes with cancer, and M describes whether the cancer has spread.
• What foods help with nausea during cancer treatment?Cold foods, bland starchy foods, and ginger foods and drinks are easy on the stomach and may ease nausea during treatment.
• What happens in a phase 1 clinical trial?In a phase 1 trial, researchers test whether a new treatment is safe, what its side effects are, and the highest dose people can tolerate, in a small group.
• What helps with memory problems during cancer treatment?Planning your day, exercising your body and mind, and using lists and planners can help manage minor memory problems during cancer treatment, according to the National Cancer Institute.
• What is a biopsy?A biopsy is a procedure in which a doctor removes a sample of abnormal tissue so a pathologist can examine it, often the only way to confirm cancer.
• What is a plasma cell neoplasm?A plasma cell neoplasm occurs when abnormal plasma cells form cancerous tumors in bone or soft tissue.
• What is a polyp in colorectal cancer?A polyp is a growth inside the colon or rectum, and colorectal cancer often begins as one of these growths.
• What is a stem cell transplant?A stem cell transplant restores blood-forming stem cells destroyed by high doses of chemotherapy or radiation therapy.
• What is chemo brain?Chemo brain is a term for memory or concentration problems—sometimes a mental fog—that can happen with some cancer treatments.
• What is graft-versus-host disease?Graft-versus-host disease can occur after a donor transplant when the donor's white blood cells attack the recipient's cells.
• What is immunotherapy?Immunotherapy is a type of cancer treatment that helps your immune system fight cancer.
• What is minimally invasive surgery?Minimally invasive surgery uses a few small cuts and a camera called a laparoscope, and usually has a shorter recovery than open surgery.
• What is neutropenia during chemotherapy?Neutropenia is a low number of neutrophils, a white blood cell that fights infection, and it raises infection risk during chemotherapy.
• What is targeted therapy?Targeted therapy is a cancer treatment that targets proteins that control how cancer cells grow, divide, and spread.
• What is the difference between a plasmacytoma and multiple myeloma?The difference is the number of tumors: one tumor is a plasmacytoma, multiple tumors are multiple myeloma.
• What is the difference between a screening test and a diagnosis?Screening tests look for cancer in people without symptoms and are not meant to diagnose cancer; an abnormal result usually leads to more tests.
• What is the difference between benign and malignant tumors?Benign tumors do not spread into nearby tissue, while malignant (cancerous) tumors can invade nearby tissue and spread to distant parts of the body.
• What is the difference between Hodgkin and non-Hodgkin lymphoma?Hodgkin and non-Hodgkin lymphoma are the two main types of lymphoma; Hodgkin can often be cured, while the outlook for NHL depends on the specific type.
• What is the difference between intestinal and diffuse stomach cancer?Intestinal and diffuse describe how stomach adenocarcinoma cells look under a microscope.
• What is the difference between palliative care and hospice?Palliative care can begin at any point during cancer treatment and go along with it, while hospice begins when curative treatment is no longer the goal and the sole focus is quality of life.
• What is the main risk factor for bladder cancer?Using tobacco, especially smoking cigarettes, is a major risk factor for bladder cancer.
• What is the most common type of liver cancer in adults?Hepatocellular carcinoma is the most common type of primary liver cancer in adults.
• What is the most common type of stomach cancer?Nearly all stomach cancers are adenocarcinomas, which start in the mucus-making cells of the stomach lining.
• What is thrombocytopenia in cancer treatment?Thrombocytopenia is a low platelet count that can happen with some cancer treatments and lead to easier bleeding and bruising.
• What questions should I ask before joining a clinical trial?Ask about the trial's purpose, its risks and benefits, your rights and privacy, the costs, and how it could affect your daily life.
• What should I eat during cancer treatment?During treatment you often need extra protein and calories, so a good cancer diet may differ from a typical healthy diet.
• What should I eat when I have diarrhea from cancer treatment?During treatment-related diarrhea, clear liquids, small meals, low-fiber foods, and foods high in sodium and potassium may help, while some foods should be avoided.
• When are mouth problems from cancer treatment serious?Mouth problems are more serious when they interfere with eating and drinking, which can lead to dehydration or malnutrition.
• When should I call my doctor about a rash during immunotherapy?Call your doctor about a severe, extensive, blistering, or painful rash during immunotherapy, especially one involving the eyes or mouth.
• When should I see a doctor about possible cancer symptoms?See a doctor if symptoms do not get better after a few weeks; do not wait to feel pain, because cancer often does not cause pain.
• Where does bladder cancer start?Bladder cancer starts in the bladder, and almost all bladder cancers begin in the cells that line the inside of the bladder.
• Where does breast cancer start?Breast cancer starts in the breast and can begin in the milk ducts, the milk-making lobules, the nipple, or other breast tissue.
• Where does cancer most often spread?Cancer can spread almost anywhere, but the most common sites are the bone, liver, and lung.
• Where in the body do head and neck cancers form?They form in the mouth, throat, voice box, sinuses and nasal cavity, and salivary glands.
• Where in the esophagus does cancer start?Esophageal cancer starts on the inside lining of the esophagus and grows outward.
• Which cancers have tumor marker tests?Tumor marker tests are used for a wide range of cancer types—some markers are linked to one cancer, others to several.
• Why can't I sleep during cancer treatment?Sleep problems during cancer treatment can be caused by treatment side effects, medicines, long hospital stays, stress, and other factors.
• Why do my hands and feet tingle during chemo?Tingling in the hands and feet during cancer treatment can happen when treatment damages sensory nerves—a condition called peripheral neuropathy, per the National Cancer Institute.
• Why do tumor marker levels go up and down?Tumor marker levels can change for several reasons, including noncancerous conditions and how a tumor is responding to treatment over time.
• Why does cancer treatment make you so tired?Cancer fatigue is extreme tiredness caused by the cancer, its treatments, and related side effects, and it isn't fully relieved by rest.
• Why does chemotherapy cause constipation?Constipation is a common side effect of some types of chemotherapy, and other treatment-related medicines can add to it.
• Why does chemotherapy cause diarrhea?Chemotherapy can cause diarrhea because it destroys rapidly dividing healthy cells that line the digestive tract along with cancer cells.
• Why does chemotherapy cause easy bleeding and bruising?Some treatments like chemotherapy lower platelets—the cells that help blood clot—so you may bruise and bleed more easily.
• Why does immunotherapy cause side effects?Immunotherapy side effects often happen when the revved-up immune system also acts against healthy cells.
• Why is metastatic breast cancer in the lung not called lung cancer?Metastatic cancer keeps the name of the original cancer, so breast cancer that spreads to the lung is called metastatic breast cancer, not lung cancer.
• Why is ovarian cancer often found late?Ovarian cancer may cause no early signs or symptoms, so it is often advanced when signs finally appear.
• Will I become addicted to pain medicine for cancer?Most people with cancer who take strong pain medicine use it safely; needing more or having withdrawal symptoms is not the same as addiction.
• Will I feel pain during cancer surgery?Anesthesia keeps you from feeling pain during surgery, though the cuts can be painful as they heal afterward.