Having hoarse voice for a long time can be a sign of laryngeal cancer

Voice is made by the vibration of vocal cords by the air from lungs. Voce becomes hoarse due to overuse of vocal cords. Vocal cords become red and swollen due to too much vibration like hands become red and swollen when clapping them too much. This swelling makes vocal cords difficult to vibrate, leading to hoarse voice.
 
Vocal cord polyp is something like a blood blister on one side of vocal cords. Blood vessels around vocal cords burst making hematoma there. Vocal cord polyp is not related to laryngeal cancer but the symptoms are both hoarse voice.
 
The cause of common hoarse voice is swelling of vocal cords so to prevent the swelling of vocal cords, moisturizing throat is important. Vocal cords don’t like dryness because they are mucus membrane. Keeping the room at proper humidity is important for vocal cords. In winter, about 1 litter (34 oz.) of water is lost a day by breathing. So it is better to drink a glass of water than to lick a candy because lost water is not made up by licking a candy. Common hoarse voice gets better within a few days.
 
If you have hoarse voice for more than 2 weeks, that can be laryngeal cancer. Cancer in vocal cords mostly doesn’t cure itself and the cancer cells increase making vocal cords heavy, resulting in difficulty of vibration and hoarse voice. Progression of cancer causes symptoms such as pain, difficulty of swallowing but at the beginning, hoarse voice is the only symptom. If hoarse voice continues for a long time, it is better to consult a doctor.