Clinically significant RRP is defined as 1) a history of symptomatic breathing, swallowing, and/or voice problems; 2) the presence of wart-like lesions in the upper aerodigestive tract; and 3) histopathology demonstrating pedunculated masses with finger-like projections of nonkeratinized stratified squamous epithelium supported by a core of highly vascularized connective tissue stroma.
A brief review of the clinical epidemiology and disease course will be presented.
The disease is rare; the incidence is approximately 1 per 100000 per year. RRP is diagnosed in both children and in adults and the disease course is variable. In the overwhelming majority of cases, the disease is caused by only two types of vaccine-preventable HPV: 6 or 11. While HPV (even if limited to type 6 and 11) is relatively common it is unknown why so few people develop RRP. The vast majority of the population either clear the virus or maintain subclinical colonization. Affected individuals often experience a heavy disease burden, undergoing many operations, and diminished quality of life due to chronic hoarseness which is often permanent.
The incidence of RRP for children born to mothers with condyloma acuminata is greatly increased in relative terms even if not in absolute terms. RRP is relatively more common among first-born children, born by vaginal delivery to a young mother (< 20 y). For adult-onset RRP, the risk factors are different: male gender and increased number of lifetime sexual partners.
Disease course in children can be very aggressive with early age of onset being associated with a more aggressive course. Regardless of age, person-to-person variability overwhelms our ability to predict a child’s clinical course. Most children experience a decrease in disease aggressiveness until going into remission a mean of 4 years after diagnosis. Adults generally experience a more indolent course and there is an association between HPV 11 and a more aggressive course. Malignant transformation and pulmonary involvement are life-threatening complications although uncommon.
RRP is a rare but potentially devastating disease caused by two “low risk” HPV types better known for causing genital warts. The epidemiologic risk factors are well described and conceivably are markers of HPV exposure by two different predominant mechanisms: vertical transmission for juvenile-onset and sexual transmission for adult-onset.