Estriol Induced Squamous Metaplasia on the Nasal Mucosa in Patients with Hereditary Hemorrhagic Telangiectasia

Abstract

The aim of this study was to evaluate by light and electron microscopy the effect of topical estriol on the nasal mucosa in patients with hereditary hemorrhagic telangiectasia (HHT). Twelve patients were instructed to apply twice daily 0.1% estriol as a nose ointment over a period of 12 months. Written consent was obtained from each patient, allowing biopsy specimens of the nasal mucosa to be taken prior to and 3, 6 and 12 months after estriol application. Metaplastic change of the nasal mucosa was observed 6 months after topical estriol application. The former ciliated columnar epithelium changed into a keratinizing squamous epithelium. The effect was reversible after discontinuation of estriol application. For the first time, we could outline the effect of topical estriol on the nasal mucosa. These histomorphological findings, and the fact that estriol is a low-potency metabolite of estradiol, make estriol a valuable agent in the treatment of HHT patients.