12 Signs of Cancer Usually Ignored By Men

Chronic coughing

A cough that lasts three weeks or more—without other symptoms, such as a cold or allergies—could be an early symptom of lung cancer. Leukemia also can lead to bronchitis-like symptoms. “If it’s different than your regular cough and if it persists, or you cough up a little blood, that’s significant,” says Dr. Markman. Some lung cancer patients report chest pain that extends up into the shoulder or down the arm.