SIGNIFICANCE OF DNA-PLOIDY AND CELL-PROLIFERATION IN JUVENILE RESPIRATORY PAPILLOMATOSIS

The clinical course of recurrent respiratory papillomatosis (RRP) in c hildren is variable and unpredictable. At present there is no way to i dentify patients at risk for aggressive disease. The objective of this study was to evaluate whether DNA ploidy and cell proliferation analy ses can predict the clinical course in children with RRP. Two differen t methods of estimating proliferation activity were compared. Nonembed ded papilloma biopsy specimens from 18 pediatric patients were analyze d by flow cytometry providing DNA content with cell cycle analysis. Th e expression of the proliferative marker Ki-67 in papilloma tissue was quantified by immunohistochemistry. The patients were prospectively o bserved for 12 to 18 months. DNA content analysis and Ki-67 expression were compared to clinical information regarding number of disease sit es, distal tracheobronchial spread, number of recurrences, need for tr acheostomy, and disease remission. High S-phase fraction, proliferativ e index, and Ki-67 expression correlated with an aggressive clinical c ourse. DNA ploidy analysis and immunodetection of proliferative marker s may assist in predicting prognosis in children with RRP.