Throat problem. Stay for so long?

I am having problem of throat problem since 7-8 months 1. Feels something stuck one side only 2. Swallowing difficulty one side left 3. Ear pain 4. Post nasal drip 5. Frequent clearing throat 6. Sometimes small amount of blood 7. Little hoarseness Went to 5 ENT's and 6 General physician , did all test from LFT, CBC, ECHO, THYROID, ENDOSCOPY, XRAY, HIV 1&2, RENAL, ANA, ETC. AND MANY MORE ENT's told it's Pharyngitis and Tonsillitis did all sort of antibiotics but not relief , nowadays constant pain in the nasopharynx area again I went to ENT and he told it's Tonsillitis. I am afraid I am suffering from CANCER, but Doctors are reluctant ... HOW CAN TONSILLITIS OR PHARYNGITIS STAY FOR SO LONG ? I AM DEPRESSED AND FEELS LIKE DYING