Human papillomavirus in respiratory recurrent papillomatosis associated to pulmonary malignant transformation

Recurrent respiratory papillomatosis (RRP) is a rare, proliferative, chronic and benign infectious disease of the upper airways with human papillomaviruses 6 (HPV6) and HPV11 being the major causative agents. Clinically, RRP manifests as recurring exophytic papillomas in the upper airways that can spread to the lung and, in some cases, progress to pulmonary squamous cell carcinoma. In this work, we examined the HPV genomic diversity found in RRP lesions, both in cases of malignant transformation and in frequently recurring cases that did not undergo transformation. Our goal was to investigate a possible link between viral genetic diversity and disease phenotype, or clinical presentation. The results from 9 clinical samples indicate that the HPV11_A2 sublineage is as important as age for prognosis in young individuals with severe RRP. Furthermore, we do not report large deletions or duplications but rather certain nucleotidic variations/polymorphisms at the genomic level of HPV6 and 11 in the investigated samples.