Know the signs

Symptoms & early detection

Most symptoms turn out to be something minor. Knowing which changes deserve a doctor's visit — and which screenings to keep up with — is one of the most powerful things you can do for your health.

First, a reassurance: most of the symptoms below are far more often caused by something other than cancer. The point of knowing them isn't to worry — it's to know when a change deserves a conversation with your doctor.

General signs worth a doctor's visit

See a healthcare provider about any of these if they are new, unexplained, or last more than a few weeks:

  • Unexplained weight loss — losing 10 pounds or more without trying.
  • Fatigue that doesn't improve with rest — deep tiredness that interferes with daily life.
  • A lump or thickening anywhere on the body, especially the breast, testicle, neck, or armpit.
  • Changes in a mole — asymmetry, uneven borders, color changes, growth, or a sore that won't heal.
  • Persistent cough or hoarseness lasting more than three to four weeks, or coughing up blood.
  • Changes in bowel or bladder habits — ongoing constipation, diarrhea, narrow stools, blood in stool or urine.
  • Difficulty swallowing or persistent indigestion.
  • Unusual bleeding or discharge — including bleeding between periods or after menopause.
  • Persistent pain with no clear cause, especially bone pain or headaches that change over time.
  • Night sweats or fevers that keep returning without an infection.

Why "early" matters so much

For most cancers, the single biggest factor in survival is how early the disease is found. A stage I cancer is often curable with straightforward treatment; the same cancer at stage IV is much harder to treat. That is the entire logic of screening — finding cancer before it causes symptoms at all.

Screening tests that save lives

ScreeningLooks forGenerally recommended for
MammogramBreast cancerWomen, typically starting at 40–50; discuss timing with your doctor
Colonoscopy / stool testsColorectal cancerAdults starting at 45
Pap test + HPV testCervical cancerWomen 21–65
Low-dose CT scanLung cancerAdults 50–80 with a significant smoking history
PSA blood testProstate cancerMen — an individual decision to discuss with your doctor, often from 50
Skin checksSkin cancer / melanomaEveryone — self-checks monthly, professional checks as advised

Exact ages and intervals depend on your personal and family history — your doctor can tailor a screening plan to you.

When to seek care urgently

Go to urgent care or the emergency department for sudden severe symptoms: significant bleeding, sudden severe pain, difficulty breathing, new confusion, or a fever during chemotherapy (call your oncology team immediately — this can be an emergency).

Trust your instincts. You know your body better than anyone. If something feels wrong and a first appointment doesn't resolve your concern, it is always okay to ask again or seek a second opinion.