An Inflammatory Polyp-Like Benign Sinonasal Mass Lesion - Respiratory Epithelial Adenomatoid Hamartoma: A Case Report.

Respiratory epithelial adenomatoid hamartoma (REAH) is an uncommon, benign glandular proliferation that arises from the surface epithelium of the nasal cavity and paranasal sinuses. Here we report a case, wherein a 62-year male from northern Kerala presented with bilateral nasal obstruction, loss of sense of smell, and bilateral nasal discharge. On examination, a polypoidal lesion was observed in the left nasal cavity, filling the entire left middle meatus. Diagnostic nasal endoscopy revealed a multilobulated polypoidal mass in the left nasal cavity extending posteriorly into the nasopharynx and causing partial occlusion of the (R) choana. Computerized tomography(CT) imaging was suggestive of a mass in (L) nasal cavity extending from the frontal sinus to the inferior turbinate and posteriorly extending into the nasopharynx. The patient underwent Endoscopic endonasal excision of the (L)nasal mass and intraoperatively the mass was seen to arise from the septum in the (L) nasal cavity posteriorly. Histopathological examination confirmed the diagnosis of REAH. This case report emphasizes the significance of including REAH in the differential diagnosis of sinonasal masses as it simulates other inflammatory disorders. Appropriate diagnosis by biopsy prevents unnecessary aggressive surgery as this benign condition mimics malignant lesions. More research is needed to understand the etiopathogenesis and diagnostic usefulness of immunohistological staining in REAH.