Contemporary cohort cross-sectional study. Introduction: Despite its importance for an accurate diagnosis, histology differences among nasal polyps and its clinical implications are rarely reported in the literature. The existing papers classify polyp samples without concern for prior treatments, which could influence the results attained. AIMS: carry out a morphological study, through light microscopy, of nasal polyps' structural alterations in the absence of any type of prior treatment and histologically classify it in relation to studies published in the literature. MATERIALS AND METHODS: We studied 89 patients with nasosinusal polyps without prior treatment. Polyp samples were collected by outpatient biopsy and analyzed through light microscopy after dyeing with hematoxylin-eosin. RESULTS: Samples were classified in the following way: Edematous or eosinophilic polyp 65 cases (73%); fibro-inflammatory polyp: 16 cases (18%); Polyp with Sero-mucinose gland hyperplasia: 06 cases (6.7%) and polyp with stroma atypia: 2 cases (2.3%). DISCUSSION: eosinophilic pattern prevailed in the patients with nasosinusal polyps of the population studied. This pattern is similar to the ones found in the major studies, which, however, do not mention prior treatment. CONCLUSION: after analyzing the polyps' histological characteristics, we noticed that the untreated polyps present a predominantly eosinophilic pattern.
biopsy; histological classification; light microscopy; nasal polyp
