In most cases, the best time to diagnose cancer is before it produces any signs or symptoms at all. But, if this is not possible, it is important to know what kind of clinical findings may indicate cancer. A sign is an objective indicator of an abnormality or problem usually detected and interpreted by a physician. Examples include blood pressure, temperature, masses, and weight loss. A symptom is a subjective report provided by the patient. Examples include pain, dizziness, and headache. According to the National Cancer Institute, the most common signs and symptoms of cancer include:

  • Thickening or lump in the breast or any other part of the body, including persistent swelling in the lymph nodes
  • Conspicuous change in a wart or mole
  • Sore that does not heal
  • Nagging cough or hoarseness
  • Persistent changes in bowel or bladder habits
  • Persistent indigestion or difficulty swallowing
  • Unexplained changes in weight (up or down), or change in girth
  • Unusual bleeding or discharge

Certainly, in most cases these symptoms are not caused by cancer. They may be due to infections, benign tumors, or other medical problems. However, if you are experiencing any of these symptoms, your doctor should be the one to make the determination.

Your doctor will take a complete medical history and perform a routine physical examination. The history will include important information such as a detailed description of your current symptoms, past and ongoing illnesses, family history of cancer, or exposure to known or suspected cancer causing agents. During the physical exam, your doctor will carefully check for any suspicious abnormalities such as masses, alterations in the skin texture or color, or an unusual swelling in the lymph nodes or other organs. To learn more about the possible causes of cancer, see the causes of cancer section in Cancer 101.

Your doctor will combine all the information from your history and physical exam to determine the likelihood of cancer. Based on this assessment, he or she may either perform specific tests designed to detect the cancer or, if a cancer diagnosis is unlikely, teach you what signs and symptoms to look for in the future.