Proliferative activity and cytometric characteristics in polyps of the nasal cavity and paranasal sinuses

Although several investigations have revealed the influence of cytokines, a llergy, and environmental factors in polyp development, the etiology of nas al polyps is still unknown. To estimate the biology of this common disease the operative specimens of 50 patients who underwent surgery for polyps of the nasal cavity and the paranasal sinuses were examined; of these, 10 pati ents had recurrent disease and 23 patients had an allergy. The investigatio ns included routine histology and quantitative DNA measurements, along with immunohistochemical identification of proliferation markers (i.e., MIB-1; proliferating cell nuclear antigen, PCNA). Histologically, most polyps reve aled an infiltration with lymphocytes, eosinophilic granulocytes, and plasm a cells. Twenty-five percent had a squamous metaplasia of the respiratory e pithelium. Quantitative DNA analysis demonstrated diploid stemlines and lac k of aneuploid cells with a DNA content exceeding 5c in most cases. Immunoh istochemical detection of proliferation markers showed low proliferation ra tes in all cases. In 27 polyps no MIB-1 expression was detected, and in 7 p olyps no PCNA expression was detected. The polyps of the 23 patients with p roven allergic diathesis did not reveal higher scores for the parameters of DNA analysis (i.e., ploidy status and percentage of aneuploid cells) and p roliferation scores. Nasal polyps of 10 patients with recurrent disease dis played higher scores for proliferation markers, and in five cases aneuploid cells with 5c exceeding rate (5cER) of 1.5-11.7% were detected According t o these results, polyps of the nasal cavity and paranasal sinuses showed lo w proliferation scores and were diploid. The data demonstrated that there w as no increase of proliferation activity or ploidy shift toward aneuploidy in patients with allergy. Nevertheless, in recurrent disease some increase in proliferation activity and some changes in the parameters of the DNA ana lysis occurred, indicating more aggressive behavior of recurrent polyps in single cases.