A standardized list of cancer warning signs promotes early detection as a public health strategy. Organizations like the American Cancer Society created this list to empower individuals to recognize potential bodily changes that warrant professional evaluation. Recognizing these signs helps identify cancer at an earlier, more treatable stage. This list is a guide intended to prompt a conversation with a healthcare provider about persistent or unusual symptoms, not a diagnostic tool.
The Seven Warning Signs of Cancer
The seven classic warning signs are grouped using the mnemonic “CAUTION” to help people remember them. Each letter represents a distinct change in bodily function or appearance that could be an early indicator of cancer. These signs focus on noticeable physical changes that are not typical for the individual and do not resolve.
Change in Bowel or Bladder Habits (C)
A persistent alteration in how often or how easily a person urinates or passes stool can be significant. This includes chronic constipation or diarrhea lasting several weeks, or a change in stool size or shape. Bladder changes might involve pain during urination, a frequent urge, or blood in the urine. These symptoms may suggest cancers affecting the colon, rectum, bladder, or prostate.
A Sore That Does Not Heal (A)
Any sore on the skin or in the mouth that takes an unusually long time to heal should be examined. A non-healing lesion persisting for several weeks could indicate skin or oral cancer. This sign is concerning if the sore also bleeds easily, grows larger, or becomes painful.
Unusual Bleeding or Discharge (U)
Unexpected bleeding from any body opening or unusual discharge needs medical attention. Examples include unexplained vaginal bleeding between periods or after menopause, blood in the stool or urine, or bloody discharge from a nipple. This symptom can be associated with cancers of the colon, cervix, uterus, bladder, or kidney.
Thickening or Lump in the Breast or Elsewhere (T)
The discovery of a new lump or area of thickening tissue anywhere in the body is a common warning sign. Though many lumps are benign cysts or fatty tumors, a firm, painless mass that grows over time should be immediately evaluated. This sign is most frequently associated with breast cancer, testicular cancer, or soft tissue sarcomas.
Indigestion or Difficulty Swallowing (I)
Persistent indigestion, heartburn, or a sensation that food is getting stuck in the throat can be symptoms of concern, especially if they are new or worsening. This difficulty, medically termed dysphagia, can indicate a problem in the esophagus, stomach, or pharynx. If these issues do not improve with common remedies or last for more than a few weeks, professional assessment is required.
Obvious Change in a Wart or Mole (O)
A change in the size, shape, color, or texture of a mole or wart is a possible indicator of melanoma, a serious form of skin cancer. The ABCDE rule helps identify concerning changes: Asymmetry, Border irregularity, Color variation, Diameter greater than six millimeters, and Evolving appearance. Any mole that starts to itch, bleed, or change rapidly should be checked by a dermatologist.
Nagging Cough or Hoarseness (N)
A cough or hoarseness lasting an extended period, typically four weeks or longer, without an obvious cause like a respiratory infection, can be a warning sign. This persistent irritation can be linked to cancers of the lung, larynx, or thyroid. A chronic cough that is particularly deep or produces blood should be investigated, along with prolonged changes to the voice.
Recognizing That Symptoms Are Not a Diagnosis
While the “CAUTION” signs are an important alert system, noticing one does not automatically mean a person has cancer. Many common, non-serious conditions share the same symptoms, making it easy to mistake a benign issue for something more concerning. For example, a nagging cough is more likely caused by allergies, asthma, or a cold than by lung cancer.
A lump found in the breast is often a benign cyst, and blood in the stool may be due to hemorrhoids. The temporary presence of a symptom is less concerning than its persistence or worsening over time. If a symptom lasts for several weeks and does not resolve, a medical opinion becomes necessary.
A definitive cancer diagnosis relies on professional medical testing, including imaging scans, blood work, or a biopsy. A biopsy involves removing a small tissue sample for examination under a microscope by a pathologist. This is the only way to confirm the presence of malignant cells and determine the specific type of cancer.
Next Steps After Noticing a Change
The appropriate action after recognizing a persistent change is to schedule an appointment with a healthcare provider promptly. When preparing for this visit, track the symptom’s characteristics, such as when it started, how often it occurs, and if anything makes it better or worse. Being specific about the duration and severity ensures the provider has necessary details for a thorough evaluation.
Bring a list of all current medications, including over-the-counter drugs or supplements, as these can influence symptoms or interact with tests. Be honest about any concerns, even if they seem minor. The provider’s role is to investigate the change and determine its cause.
Awareness of warning signs works alongside routine preventative screenings, such as mammograms, colonoscopies, and Pap tests. These screenings are designed to detect cancer before symptoms appear, offering the best chance for early and effective treatment. Symptom awareness and routine screening are complementary strategies for maintaining health.