What are cancer’s symptoms? 10 signs you shouldn’t ignore

One in 3 people will get cancer during their lifetimes and around 600,000 will die from it in the United States each year.  But the good news is there are things you can do to catch cancer early when it’s easiest to treat.

First, keep up to date with your cancer screenings.

Second, be aware of how your body looks and feels, and be on the lookout for changes. Cancer symptoms can be vague, and they can resemble other conditions or health concerns.

We talked to Therese Bevers, M.D., medical director of MD Anderson’s Cancer Prevention Center, about some common cancer symptoms.

Talk to your doctor if you see or feel any of the following:

Cancer symptoms

Mass/lump: If you see or feel a new lump or mass that’s been there for a few weeks or is growing, get it checked out. Many lumps are not cancer and your doctor may be able to tell you right away. Sometimes, more testing is needed. Maybe an ultrasound, CT scan or MRI.

Unexplained weight loss: Most adults do not lose weight without effort, so if you are losing weight without going on a diet or exercise program, talk to your doctor. Weight loss of 10 or more pounds that cannot be explained could be a sign of cancer. Stomach, liver and pancreas cancers can all cause loss of appetite. Colon cancer can prevent the colon from properly absorbing food and nutrients, causing weight loss.  Other cancers can cause mild nausea which may mean you eat less. But weight loss is not always a sign of cancer. It could be that you have lost your appetite or are skipping meals for other reasons like stress or depression.

Pain: Don’t ignore pain. If you have new and ongoing discomfort, get it checked out. But bear in mind that many cancers don’t hurt. So if you have a lump that hasn’t gone away, get it checked out, even if it doesn’t hurt. Most breast cancers are not painful and a growing mass that’s not painful is concerning.

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Change in bowel or bladder habits: This can mean blood in the urine or stool, or changes in the stool. For example, your stool may be pencil thin or black. Any of these could be a sign of colon cancer. For men, urinating more often can be a sign of prostate cancer, because it may mean you are not emptying your bladder fully. Having more difficulty urinating also can be a sign of prostate cancer, although more commonly is it because of another less serious condition.

For women, unless you’re pregnant or drinking more water, urinating more often can be a sign of gynecologic cancers. Take note if you also feel full, have abdominal pain and experience bloating.

Not every urinary symptom is cancer, but if you are concerned, or a problem is persistent after treatment, talk to your doctor or seek a second opinion.

Fatigue: This is more than feeling tired after a busy day. Ask yourself, does my tiredness limit my activities? If you can’t get out of bed to go to work or do something fun with friends, even if you seem to have had enough rest, that’s a concern. There are a lot of other diseases that can cause tiredness though, so fatigue is not the number one symptom of cancer. Talk to your doctor.

A sore that doesn’t heal: It doesn’t matter where it is. If you have a sore that doesn’t heal, it should be checked out. Ulcers on the nipple can be sign of breast cancer. And of course, sores on the skin that don't heal can be a sign of skin cancer.

Inside your mouth, the sore might look like an area that is whiter and doesn’t scrape off, or an area that’s redder and doesn’t go away. Both of those could be signs of oral cancer. Ask your dentist about oral cancer screening. Dentists can look for color changes and can also run their fingers all around your mouth to look for a mass.

RELATED: 10 cancer symptoms men shouldn't ignore

Change in a mole or wart – or any skin change: Everyone should be aware of how their moles, freckles and warts look. That way, if anything changes, you can tell your doctor. You can use the ABC guide to track changes in your moles.

People at higher risk of skin cancer should get a full-body skin cancer screening from their dermatologist every year. This includes people with fair skin and red hair, more than 50 moles and people who’ve been exposed to a lot of sun or tanning beds. If you have a family history of melanoma or a personal history of skin cancer, annual screenings are also recommended. Here is a full list of who is at higher risk of skin cancer.

Unusual bleeding or discharge: Seeing fluids where you don’t normally see them can be a sign of cancer. If you are a woman, this could be vaginal bleeding or discharge different from what is normal for you. It could also be bloody discharge form the nipple.

Indigestion or trouble swallowing: There are some benign throat conditions that can cause problems with swallowing, but indigestion or trouble swallowing also can be a sign of esophageal cancer. If you are having trouble swallowing, perhaps with pills or meat, talk to your doctor. If you’ve been having indigestion as well, that makes it more of a concern.

Nagging cough or hoarseness: A persistent cough or hoarseness can be a sign of lung cancer. Hoarseness can also be a sign of tumors on or near the vocal cords.

Lung cancer kills more people than any other cancer, so it’s important to watch out for these symptoms, especially if you are a smoker.

How to talk to your doctor about cancer

Physicians will often allow a few weeks to see if your symptoms improve or get worse. Even if you think your symptoms are mild, don't hesitate to talk to your doctor.

 “A clinician should evaluate your symptoms and suggest testing or treatment if needed, then ask you to come back if the problem persists or gets worse,” says Therese Bevers, medical director of MD Anderson’s Cancer Prevention Center.

Remember, any ongoing symptom should be evaluated. And be sure to follow up.