I am 23 yes old male. I had sore throat for last 5yrs or more. It never created any trouble for me, but recently I was suffering from cold and flu, till then my voice has changed a lot. After taking homeopathic treatment for last 3/4 weeks, my voice has improved a bit, but I still have the sore throat. I noticed that whenever I try drink water from a bottle continously by holding it tilted upside-down water goes into the air intake tube. I can t drink like that anymore. And I also noticed that I can t hold breath while keeping my mouth open. The air passes everytime I open my mouth. Can this be a signal of any kind of cancer? My Father died last February by lung cancer & he had same kind of symptoms like me.