When Should You Worry About a Symptom?

Everyone gets aches, lumps, coughs, and tired days. Almost all of the time, these come from ordinary causes: a virus, a pulled muscle, stress, or simply getting older, not cancer. Still, a few patterns are worth paying attention to. Catching any problem early, cancer or not, makes it easier to treat.

The National Cancer Institute says that if you have symptoms that do not get better after a few weeks, see your doctor so problems can be diagnosed and treated as early as possible. A symptom that is new for you, unexplained, or different from your normal is more worth checking than one you've had for years without change. Only a doctor can tell whether a symptom is caused by cancer or by something else, so the goal is not to self-diagnose. It is to bring the right things to the right appointment.

Cancer can show up in many different ways, which is part of why it is easy to miss. The National Cancer Institute lists examples across the body, including:

• Breast: a lump, a firm area, nipple discharge, or dimpling of the skin.
• Digestive: blood in the stool, a change in bowel habits, ongoing heartburn or indigestion, trouble swallowing, or belly pain.
• Urinary: pain or difficulty urinating, or blood in the urine.
• Skin: a new or changing mole, a sore that will not heal, or yellowing skin.
• General: unexplained weight loss or gain, ongoing fatigue, unexplained fever or night sweats, or unusual bleeding or bruising.
• Lymph nodes: new swelling or a lump in the neck, underarm, groin, or belly.
• Neurological: new headaches, seizures, vision or hearing changes, or facial drooping.

No single symptom on this list means cancer. Most of the time, each one has a far more common, benign explanation. A cough is usually a cold. A lump is often a cyst or swollen gland. The list matters because it tells you which changes are worth mentioning to a doctor, rather than shrugging off.

Cancer does not always hurt, especially early on. So the absence of pain is not a reason to wait, and the presence of pain is not proof of cancer either. If something feels off and does not settle within a few weeks, that is reason enough to ask.

Many people put off an appointment because the symptom feels too small to mention, or because they worry about wasting a doctor's time. Doctors would much rather reassure you about something harmless than have you wait on something that needed attention. There is no such thing as a silly question about your own body. Bringing up a symptom is not an overreaction. It is the entire point of having a doctor.

It also helps to remember that most people who get a symptom checked do not have cancer. The purpose of checking is not to expect the worst. It is to let a trained person, rather than a search engine, tell you what is actually going on.

A vague worry is harder to act on than a specific one. Before your visit, try to answer: When did it start? Has it changed, or stayed the same? What makes it better or worse? Have you had it before? Write the answers down. Under stress, details are easy to forget once you're in the room with a doctor, and a short note helps you say what you mean the first time.

See a doctor for any symptom that lasts more than a few weeks, keeps getting worse, or worries you, even if you cannot explain why. Bringing it up early is not overreacting. It is exactly what doctors want you to do, and most of the time, the news is reassuring. Getting checked costs you a short appointment. Waiting on something serious can cost you time that mattered.

If you are trying to make sense of one specific symptom, start with a focused guide: blood in urine, rectal bleeding, nosebleeds, changes in stool shape, vulvar itching, vaginal discharge, testicular pain, and arm or leg swelling.

Most of this page is about symptoms that give you time. A few do not.

• Call 911 or go to an emergency department if one side of the face droops, an arm or leg goes weak or numb without warning, speech turns slurred, vision drops away, or a seizure happens. Sudden chest pain, real trouble breathing, or heavy bleeding you cannot control belong here too.
• Call your care team the same day if you are coughing up blood, cannot swallow, or feel very unwell with a temperature of 100.4°F (38°C) or higher.
• Call your care team within a day or two if any symptom on this page has run past a few weeks, keeps building, or simply worries you and will not leave your mind.

• National Cancer Institute — Symptoms of Cancer.