The prevalence of human papilloma virus infection in sinonasal inverted papilloma specimens classified by histological grade
Methods: Fifty-seven paraffin-embedded specimens of Korean population were available for study. Each specimen was graded according to a four-stage histological grading system (stages I and II, benign IP; stage III, dysplastic IP; stage IV, carcinoma arising from IP). A representative section of IP specimen was isolated through laser capture microdissection (7.5- to 10-m laser spot size). Subsequently, DNA extraction and HPV genotyping with the HPV DNA chip test (Biomed Lab Co., Seoul, Korea) was performed. The HPV DNA chip contained 22 type-specific probes that consisted of 15 high-risk subtypes and 7 low-risk subtypes.
Results: Histological grading was as follows: 5, grade I; 23, grade II; 22, grade III; and 7, grade IV. Seven of 57 specimens (12.3%) showed HPV DNA. All of the HPV+ cases showed HPV DNA in early grade (grades I and II) IP lesions. No higher grade (grades III and IV) IP tumors showed HPV DNA. Among the seven HPV+ cases, five were high-risk subtypes and two were unspecified subtypes.
Conclusion: HPV infection, mainly high-risk subtypes, occurs in benign IP as an early event during the multistep tumorigenesis of IP. Cumulative other genetic insults may be required to progress from benign IP (grades I and II) to dysplastic IP (grade III) and carcinoma arising from IP (grade IV).
Document Type: Research Article
Affiliations: 1: Department of Pathology, Medical Research Institute, Pusan National University School of Medicine, Busan, Korea 2: Department of Otorhinolaryngology, Medical Research Institute, Pusan National University School of Medicine, Busan, Korea 3: Cleveland Clinic Head and Neck Institute, Cleveland, Ohio
Publication date: 2007-11-01