Cancer

Cancer refers to any one of a large number of diseases characterized by the development of abnormal cells that divide uncontrollably and have the ability to infiltrate and destroy normal body tissue. Cancer often has the ability to spread throughout your body.

Cancer is the second-leading cause of death in the world. But survival rates are improving for many types of cancer, thanks to improvements in cancer screening, treatment and prevention.

Symptoms

Signs and symptoms caused by cancer will vary depending on what part of the body is affected.

Some general signs and symptoms associated with, but not specific to, cancer, include:

  • Fatigue
  • Lump or area of thickening that can be felt under the skin
  • Weight changes, including unintended loss or gain
  • Skin changes, such as yellowing, darkening or redness of the skin, sores that won’t heal, or changes to existing moles
  • Changes in bowel or bladder habits
  • Persistent cough or trouble breathing
  • Difficulty swallowing
  • Hoarseness
  • Persistent indigestion or discomfort after eating
  • Persistent, unexplained muscle or joint pain
  • Persistent, unexplained fevers or night sweats
  • Unexplained bleeding or bruising

When to see a doctor

Make an appointment with your doctor if you have any persistent signs or symptoms that concern you.

If you don’t have any signs or symptoms, but are worried about your risk of cancer, discuss your concerns with your doctor. Ask about which cancer screening tests and procedures are appropriate for you.

Causes

Cancer is caused by changes (mutations) to the DNA within cells. The DNA inside a cell is packaged into a large number of individual genes, each of which contains a set of instructions telling the cell what functions to perform, as well as how to grow and divide. Errors in the instructions can cause the cell to stop its normal function and may allow a cell to become cancerous.

What do gene mutations do?

A gene mutation can instruct a healthy cell to:

  • Allow rapid growth. A gene mutation can tell a cell to grow and divide more rapidly. This creates many new cells that all have that same mutation.
  • Fail to stop uncontrolled cell growth. Normal cells know when to stop growing so that you have just the right number of each type of cell. Cancer cells lose the controls (tumor suppressor genes) that tell them when to stop growing. A mutation in a tumor suppressor gene allows cancer cells to continue growing and accumulating.
  • Make mistakes when repairing DNA errors. DNA repair genes look for errors in a cell’s DNA and make corrections. A mutation in a DNA repair gene may mean that other errors aren’t corrected, leading cells to become cancerous.

These mutations are the most common ones found in cancer. But many other gene mutations can contribute to causing cancer.

What causes gene mutations?

Gene mutations can occur for several reasons, for instance:

  • Gene mutations you’re born with. You may be born with a genetic mutation that you inherited from your parents. This type of mutation accounts for a small percentage of cancers.
  • Gene mutations that occur after birth. Most gene mutations occur after you’re born and aren’t inherited. A number of forces can cause gene mutations, such as smoking, radiation, viruses, cancer-causing chemicals (carcinogens), obesity, hormones, chronic inflammation and a lack of exercise.

Gene mutations occur frequently during normal cell growth. However, cells contain a mechanism that recognizes when a mistake occurs and repairs the mistake. Occasionally, a mistake is missed. This could cause a cell to become cancerous.

How do gene mutations interact with each other?

The gene mutations you’re born with and those that you acquire throughout your life work together to cause cancer.

For instance, if you’ve inherited a genetic mutation that predisposes you to cancer, that doesn’t mean you’re certain to get cancer. Instead, you may need one or more other gene mutations to cause cancer. Your inherited gene mutation could make you more likely than other people to develop cancer when exposed to a certain cancer-causing substance.

It’s not clear just how many mutations must accumulate for cancer to form. It’s likely that this varies among cancer types.

Risk factors

While doctors have an idea of what may increase your risk of cancer, the majority of cancers occur in people who don’t have any known risk factors. Factors known to increase your risk of cancer include:

Your age

Cancer can take decades to develop. That’s why most people diagnosed with cancer are 65 or older. While it’s more common in older adults, cancer isn’t exclusively an adult disease — cancer can be diagnosed at any age.

Your habits

Certain lifestyle choices are known to increase your risk of cancer. Smoking, drinking more than one drink a day for women and up to two drinks a day for men, excessive exposure to the sun or frequent blistering sunburns, being obese, and having unsafe sex can contribute to cancer.

You can change these habits to lower your risk of cancer — though some habits are easier to change than others.

Your family history

Only a small portion of cancers are due to an inherited condition. If cancer is common in your family, it’s possible that mutations are being passed from one generation to the next. You might be a candidate for genetic testing to see whether you have inherited mutations that might increase your risk of certain cancers. Keep in mind that having an inherited genetic mutation doesn’t necessarily mean you’ll get cancer.

Your health conditions

Some chronic health conditions, such as ulcerative colitis, can markedly increase your risk of developing certain cancers. Talk to your doctor about your risk.

Your environment

The environment around you may contain harmful chemicals that can increase your risk of cancer. Even if you don’t smoke, you might inhale secondhand smoke if you go where people are smoking or if you live with someone who smokes. Chemicals in your home or workplace, such as asbestos and benzene, also are associated with an increased risk of cancer.

Complications

Cancer and its treatment can cause several complications, including:

  • Pain. Pain can be caused by cancer or by cancer treatment, though not all cancer is painful. Medications and other approaches can effectively treat cancer-related pain.
  • Fatigue. Fatigue in people with cancer has many causes, but it can often be managed. Fatigue associated with chemotherapy or radiation therapy treatments is common, but it’s usually temporary.
  • Difficulty breathing. Cancer or cancer treatment may cause a feeling of being short of breath. Treatments may bring relief.
  • Nausea. Certain cancers and cancer treatments can cause nausea. Your doctor can sometimes predict if your treatment is likely to cause nausea. Medications and other treatments may help you prevent or decrease nausea.
  • Diarrhea or constipation. Cancer and cancer treatment can affect your bowels and cause diarrhea or constipation.
  • Weight loss. Cancer and cancer treatment may cause weight loss. Cancer steals food from normal cells and deprives them of nutrients. This is often not affected by how many calories or what kind of food is eaten; it’s difficult to treat. In most cases, using artificial nutrition through tubes into the stomach or vein does not help change the weight loss.
  • Chemical changes in your body. Cancer can upset the normal chemical balance in your body and increase your risk of serious complications. Signs and symptoms of chemical imbalances might include excessive thirst, frequent urination, constipation and confusion.
  • Brain and nervous system problems. Cancer can press on nearby nerves and cause pain and loss of function of one part of your body. Cancer that involves the brain can cause headaches and stroke-like signs and symptoms, such as weakness on one side of your body.
  • Unusual immune system reactions to cancer. In some cases the body’s immune system may react to the presence of cancer by attacking healthy cells. Called paraneoplastic syndromes, these very rare reactions can lead to a variety of signs and symptoms, such as difficulty walking and seizures.
  • Cancer that spreads. As cancer advances, it may spread (metastasize) to other parts of the body. Where cancer spreads depends on the type of cancer.
  • Cancer that returns. Cancer survivors have a risk of cancer recurrence. Some cancers are more likely to recur than others. Ask your doctor about what you can do to reduce your risk of cancer recurrence. Your doctor may devise a follow-up care plan for you after treatment. This plan may include periodic scans and exams in the months and years after your treatment, to look for cancer recurrence.

Prevention

Doctors have identified several ways to reduce your risk of cancer, such as:

  • Stop smoking. If you smoke, quit. If you don’t smoke, don’t start. Smoking is linked to several types of cancer — not just lung cancer. Stopping now will reduce your risk of cancer in the future.
  • Avoid excessive sun exposure. Harmful ultraviolet (UV) rays from the sun can increase your risk of skin cancer. Limit your sun exposure by staying in the shade, wearing protective clothing or applying sunscreen.
  • Eat a healthy diet. Choose a diet rich in fruits and vegetables. Select whole grains and lean proteins. Limit your intake of processed meats.
  • Exercise most days of the week. Regular exercise is linked to a lower risk of cancer. Aim for at least 30 minutes of exercise most days of the week. If you haven’t been exercising regularly, start out slowly and work your way up to 30 minutes or longer.
  • Maintain a healthy weight. Being overweight or obese may increase your risk of cancer. Work to achieve and maintain a healthy weight through a combination of a healthy diet and regular exercise.
  • Drink alcohol in moderation, if you choose to drink. If you choose to drink alcohol, do so in moderation. For healthy adults, that means up to one drink a day for women and up to two drinks a day for men.
  • Schedule cancer screening exams. Talk to your doctor about what types of cancer screening exams are best for you based on your risk factors.
  • Ask your doctor about immunizations. Certain viruses increase your risk of cancer. Immunizations may help prevent those viruses, including hepatitis B, which increases the risk of liver cancer, and human papillomavirus (HPV), which increases the risk of cervical cancer and other cancers. Ask your doctor whether immunization against these viruses is appropriate for you.

Common Cold

The common cold is an illness affecting your nose and throat. Most often, it’s harmless, but it might not feel that way. Germs called viruses cause a common cold.

Often, adults may have two or three colds each year. Infants and young children may have colds more often.

Most people recover from a common cold in 7 to 10 days. Symptoms might last longer in people who smoke. Most often, you don’t need medical care for a common cold. If symptoms don’t get better or if they get worse, see your health care provider.

Illnesses of the nose and throat caused by germs are called upper respiratory tract infections.

Symptoms

Most often, common cold symptoms start 1 to 3 days after someone is exposed to a cold virus. Symptoms vary. They can include:

  • Runny or stuffy nose.
  • Sore or scratchy throat.
  • Cough.
  • Sneezing.
  • Generally feeling unwell.
  • Slight body aches or a mild headache.
  • Low-grade fever.

The mucus from your nose may start out clear and become thicker and yellow or green. This change is normal. Most often, it doesn’t mean that you have a bacterial illness.

When to see a doctor

For adults. Most often, you don’t need medical care for a common cold. But see your health care provider if you have:

  • Symptoms that get worse or do not get better.
  • Fever greater than 101.3 degrees Fahrenheit (38.5 degrees Celsius) that lasts more than three days.
  • Fever returning after a fever-free period.
  • Shortness of breath.
  • Wheezing.
  • Intense sore throat, headache or sinus pain.

For children. Most children with a common cold don’t need to see a health care provider. Get medical care right away if your child has any of the following:

  • Fever of 100.4 degrees Fahrenheit (38 degrees Celsius) in newborns up to 12 weeks.
  • Rising fever or fever lasting more than two days in a child of any age.
  • More-intense symptoms, such as headache, throat pain or cough.
  • Trouble with breathing or wheezing.
  • Ear pain.
  • Fussiness or drowsiness that isn’t typical.
  • No interest in eating.

Causes

Many viruses can cause a common cold. Rhinoviruses are the most common cause.

A cold virus enters the body through the mouth, eyes or nose. The virus can spread by:

  • Droplets in the air when someone who is sick coughs, sneezes or talks.
  • Hand-to-hand contact with someone who has a cold.
  • Sharing objects with the virus on them, such as dishes, towels, toys or telephones.
  • Touching your eyes, nose or mouth after contact with the virus.

Risk factors

These factors can increase the chances of getting a cold:

  • Age. Infants and young children have a greater risk of colds than other people, especially if they spend time in child care settings.
  • Weakened immune system. Having a long-term illness or weakened immune system increases your risk.
  • Time of year. Both children and adults are more likely to get colds in fall and winter.
  • Smoking. Smoking or being around secondhand smoke increases the risk of catching a cold.
  • Exposure. Being in crowds, such as at school or on an airplane, increases the chance of getting a cold.

Complications

These conditions can occur along with your cold:

  • Middle ear infection. This is the swelling and build-up of fluids in the space behind the eardrum. It may be caused by a virus or bacteria. Typical signs and symptoms include earaches or the return of a fever following a common cold.
  • Asthma. A cold can trigger wheezing, even in people who don’t have asthma. For people with asthma, a cold can make it worse.
  • Sinusitis. In adults or children, a common cold that lasts a while can lead to swelling and pain in the sinuses. These are air-filled spaces in the skull above the eyes and around the nose. A virus or bacteria may cause sinusitis.
  • Other illnesses. A common cold can lead to illnesses of the lungs, such as pneumonia or bronchitis. People with asthma or weakened immune systems have an increased risk of these conditions.

Prevention

There’s no vaccine for the common cold. You can take these steps to slow the spread of the virus and prevent illness:

  • Wash your hands. Wash your hands well and often with soap and water for at least 20 seconds. If soap and water aren’t available, use an alcohol-based hand sanitizer with at least 60% alcohol. Teach your children the importance of hand-washing. Try not to touch your eyes, nose or mouth with unwashed hands.
  • Clean and disinfect. Clean and disinfect surfaces that are touched often. These include doorknobs, light switches, electronics, and kitchen and bathroom countertops. This is especially important when someone in your family has a cold. Wash children’s toys often.
  • Cover your cough. Sneeze and cough into tissues. Throw away used tissues right away, and then wash your hands. If you don’t have a tissue, sneeze or cough into the bend of your elbow, and then wash your hands.
  • Don’t share. Don’t share drinking glasses or silverware with other family members.
  • Stay away from people with colds. Avoid close contact with anyone who has a cold. Stay out of crowds when possible. Try not to touch your eyes, nose and mouth when you’re in crowds.
  • Review your child care center’s policies. Look for a child care setting with good hygiene practices and clear policies about keeping sick children at home.
  • Take care of yourself. Eat well, exercise and get plenty of sleep to help you stay healthy.

Common cold symptoms cartoon style infographic illustration

What is WART?

Common warts are small, grainy skin growths that occur most often on your fingers or hands. Rough to the touch, common warts also often feature a pattern of tiny black dots, which are small, clotted blood vessels.

Common warts are caused by a virus and are transmitted by touch. It can take a wart as long as two to six months to develop after your skin has been exposed to the virus. Common warts are usually harmless and eventually disappear on their own. But many people choose to remove them because they find them bothersome or embarrassing.

Symptoms

Common warts usually occur on your fingers or hands and may be:

  • Small, fleshy, grainy bumps
  • Rough to the touch
  • Sprinkled with black pinpoints, which are small, clotted blood vessels

When to see a doctor

See your doctor for common warts if:

  • The growths are painful or change in appearance or color
  • You’ve tried treating the warts, but they persist, spread or recur
  • The growths are bothersome and interfere with activities
  • You aren’t sure whether the growths are warts
  • You are an adult and numerous warts begin to appear, which may indicate the immune system is malfunctioning

Causes

Common warts are caused by the human papillomavirus (HPV). The virus is quite common and has more than 150 types, but only a few cause warts on your hands. Some strains of HPV are acquired through sexual contact. Most forms, however, are spread by casual skin contact or through shared objects, such as towels or washcloths. The virus usually spreads through breaks in your skin, such as a hangnail or a scrape. Biting your nails also can cause warts to spread on your fingertips and around your nails.

Each person’s immune system responds to the HPV virus differently, so not everyone who comes in contact with HPV develops warts.

Risk factors

People at higher risk of developing common warts include:

  • Children and young adults, because their bodies may not have built up immunity to the virus
  • People with weakened immune systems, such as those with HIV/AIDS or people who’ve had organ transplants

Prevention

To reduce your risk of common warts:

  • Avoid direct contact with warts. This includes your own warts.
  • Don’t pick at warts. Picking may spread the virus.
  • Don’t use the same emery board, pumice stone or nail clipper on your warts as you use on your healthy skin and nails. Use a disposable emery board.
  • Don’t bite your fingernails. Warts occur more often in skin that has been broken. Nibbling the skin around your fingernails opens the door for the virus.
  • Groom with care. And avoid brushing, clipping or shaving areas that have warts. If you must shave, use an electric razor.