is best treated by as mention by you is argon plasma coagulation is absolutely right, but non surgical management is prednisolone
60 mg as enema twice a day(dissolve 60mg of prenisolone in water and pour in to rectum as enema) .
Present lump in left side neck under ear i dont think so its metastatic lymphadenopathy
from prostate cancer
primary disease. but in doubt you must undergo FNAC(FINE NEEDLE ASPIRATION CYTOLOGY) IT definitely give clue whether it's infection or component of cancer.