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Signs and Symptoms of Cancer

A sign is an objective indicator of an abnormality or problem usually detected and interpreted by a doctor. Examples include blood pressure, temperature, masses, and weight loss. A symptom is a subjective report provided by the patient. Examples include pain, lightheadedness, or headaches. Signs and symptoms may help identify a cancer in its early stages. The earlier a cancer is detected the better the outcomes tend to be. Unfortunately in some cancers, symptoms may not appear until the cancer is in an advanced stage.

Signs and symptoms of cancer may be caused by the growth of cancer itself or pressure placed on nearby organs by tumor. The cancer can also cause body-wide symptoms like fatigue because of their demands on the body's resources, changes to blood cells or the immune system, or substances released from the cancer cells.

Some general signs or symptoms may be related to a variety of cancers. These are common signs and symptoms that can be caused by a variety of factors, most harmless. They should be checked out by a doctor, especially if the symptoms last for a long time or are getting worse. General signs and symptoms of a cancer include:

  • Skin changes, including darkening, reddening, itching, excessive hair growth, and yellowing of the skin or eyes—jaundice
  • Fever
  • Persistent pain
  • Unexplained changes in weight (up or down), or change in girth
  • Excessive fatigue with or without weakness

Other signs and symptoms are related to specific cancers. These signs and symptoms can also be caused by noncancerous factors but should be checked out by a doctor. Examples include:

  • Thickening or lump in the breast or any other part of the body, including persistent swelling in the lymph nodes
  • Persistent changes in bowel or bladder habits—could be related to intestinal, bladder, or prostate cancers
  • Spitting, coughing, or vomiting blood—may indicate lung or gastrointestinal cancers
  • Unusual bleeding or discharge, including rectal or vaginal—may indicate intestinal or gynecological cancers
  • Sore that does not heal—skin sores can indicate skin cancer while mouth sores may indicate mouth cancers
  • Conspicuous changes in a wart or mole—skin cancer factor
  • Persistent indigestion or difficulty swallowing—may indicate cancer of throat or stomach

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 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, they 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.

Revision Information

  • Cancer diagnosis. Merck Manual Professional version website. Available at: Updated July 2013. Accessed May 12, 2015.

  • Signs and symptoms of cancer. American Cancer Society website. Available at: Updated August 11, 2014. Accessed May 12, 2015.

  • Symptoms. National Cancer Institute website. Available at: Accessed May 12, 2015.