Blood in Urine or Stool – Talk to your doctor if you’re bleeding from a part of your body that normally doesn’t, especially if the bleeding lasts more than a day or two, Meyers says. Bloody stool is often from hemorrhoids, but it can also be a symptom of colon cancer. Bloody urine is usually the first sign of cancer of the bladder or kidneys, says Herbert Lepor, MD, a urologist at NYU’s Langone.

Lymph Node Changes – Lymph nodes are small, bean-shaped glands around the body. Most changes in them come from common infections. But some cancers, including leukemia and lymphoma, can also cause lymph nodes to swell. It’s a good idea to see your doctor if you have a lump or swelling anywhere in your body that lasts a month or more, Meyers says.

Trouble Swallowing – Occasional trouble swallowing is nothing to worry about. But when it happens often, especially with vomiting or weight loss, your doctor may want to check you for throat or stomach cancer.

Random Weight Loss – Most unintended weight loss is not cancer, Meyers says. “It’s often caused by stress or your thyroid, but it can be a sign of pancreatic cancer,” she says. Stomach and lung cancers are also possible. Your doctor may ask for a lot of tests to look for a problem, including blood tests and imaging tests, like a CT scan.

Heartburn – Too much food, alcohol, or stress (or all three) can cause serious heartburn. Meyers suggests that you change your diet for a week or two to see if your symptoms get better.

Mouth Changes – If you smoke, watch for white or bright-red patches inside your mouth or on your lips. Both can signal oral cancer. Ask your doctor or dentist about tests and treatment.