1. A Persistent Cough or Hoarseness
A cough that hangs around for more than three weeks — particularly one with no clear respiratory cause, deserves attention. Ongoing respiratory symptoms, including a cough lasting more than three weeks, hoarseness, or unexplained shortness of breath, are among the primary warning signs of lung-related cancers.
The ACS Cancer Facts and Figures 2025 identifies lung cancer warning signs as including a persistent cough, sputum streaked with blood, chest pain, a hoarse voice, worsening shortness of breath, and recurrent pneumonia or bronchitis — symptoms that usually don’t appear until the cancer is advanced. Because these signs tend to show up late, catching them early matters even more.
A hoarse voice that has lasted more than a couple of weeks without an obvious cause, like a cold or a lot of speaking, is also worth reporting to a doctor. It can point to cancers of the larynx or thyroid, not just the lungs.