Enlarged adenoid and adenoidectomy in adults: endoscopic approach and histopathological study. Adenoid enlargement is uncommon in adults and because examination of the nasopharynx by indirect posterior rhinoscopy is inadequate, many cases of enlarged adenoid in adults are misdiagnosed and accordingly maltreated. This study was conducted on 35 cases of enlarged adenoid aged between 20 and 42 years. The nasal endoscope was utilized to identify the adenoid mass. Adenoidectomy under transnasal endoscopic control was performed and all the excised material was sent for histopathological examination. Adenoidectomy resulted in marked improvement in 94 per cent of cases without major complications. Histopathological examination revealed non-specific inflammatory reaction in 15 cases (43 per cent), pure reactive changes, predominantly follicular hyperplasia, in two cases (6 per cent) and mixed pattern in 18 cases (51 per cent). Endoscopic follow-up for an average 17 months identified recurrence in only two patients. It was concluded that enlarged adenoid tissue in adults has some histopathological differences from that in children and adenoidectomy under transnasal endoscopic control is safe and reliable. 