Recurrent respiratory papillomatosis (RRP) is a rare disease due to chronic Human Papillomavirus infection, occurring in childhood (JoRRP) or in adults (AoRRP). PRR is characterized by a progressive obstruction by papillomas mostly affecting upper airway and more rarely lower respiratory tract (LRT), including lungs. This study describes the characteristics of Jo and AoRRP LRT at adulthood.

French and Quebecers? national retrospective study of the clinical, histological, therapeutic and prognostic characteristics with RRP-LRT.

Among the 67 patients (pts), 17 (25%) were JoRRP and 50 (75%) AoRRP. The mean age at diagnosis was 5 yrs for JoRRP and 54 yrs for AoRRP. ENT involvement was observed in all JoRRP and in 23 (46%) AoRRP. Lung involvement was observed in 11 (76%) JoRRP and 2 (4%) AoRRP. Mean latency duration between ENT and lung involvement was 26 yrs in JoRRP and 4 yrs in AoRRP. Lung CT-scan findings were cysts in 11 pts (74%) and nodules/mass in 2 (13%), predominating in the lower lobes. 13 pts (19%) had malignant transformation to squamous cell carcinoma in the trachea (n=3) and the lung (n=10). Associated factors with lung involvement were female gender, JoRRP, HPV-11, repeated desobstruction and tracheostomy while they were JoRRP, HPV-16 and presence of ENT or lung involvements for malignant transformation. Overall mortality was 9%, JoRRP form, lung involvement and malignant transformation being prognostic factors (p<0.05).

In this largest cohort of RRP LRT, the high frequency of lung involvement and malignant transformation, justify targeted screening measures and preventive therapeutic strategy.