Below are 12 early warning signs that doctors often encourage people not to ignore.

1. Unexplained Weight Loss

Losing weight without dieting or exercise—especially more than 5–10% of your body weight—can sometimes be linked to cancers affecting metabolism, such as stomach, lung, or pancreatic cancer.

2. Persistent Fatigue

Extreme tiredness that doesn’t improve with rest may signal that the body is fighting an underlying problem. Cancer cells can drain energy by altering how nutrients are used.

3. Ongoing Pain With No Clear Cause

Pain that lasts for weeks or months—especially in bones, head, or abdomen—should be checked. Persistent pain is the body’s way of saying something isn’t right.

4. Changes in Skin

Watch for:

New moles or changes in existing ones

Yellowing, darkening, or redness

Itching that won’t go away

Wounds that heal very slowly

These may sometimes be linked to internal or skin-related cancers.

5. Unusual Lumps or Swelling

Lumps under the skin—especially in the neck, breast, armpit, or groin—should always be evaluated, even if they aren’t painful.

6. Long-Lasting Cough or Hoarseness