This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ear, Subject name: ENT
[{'content': 'An elderly man had long-standing ear discharge and now presented with facial palsy, pain in the ear which is worse at night and a friable polyp in the ear with tendency to bleed. The likely diagnosis is: \nSelect and explain. \nA. CSOM with polyp, B. Malignant otitis externa, C. Carcinoma of middle ear, D. Glomus tumour', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Carcinoma of middle ear occurs in cases of long-standing ear discharge - the chronic irritation is probably its causative factor.Glomus tumour presenting as a polyp bleeds profusely on touch but the bleeding polyp or granulation tissue which is also friable is typical of carcinoma.Nocturnal pain is again a feature of carcinoma and differentiates it from CSOM. Features which should alert an otolaryngologist to possibility of carcinoma of middle ear include:Severe nocturnal painFriable granulations or a polyp with tendency to bleedFacial paralysisOtitis externa refractor) to treatment.', 'role': 'assistant'}]