[Human papilloma virus (HPV) typing in preneoplastic and neoplastic lesions of the uterine cervix in the IX region-Chile]

Abstract

Background: Uterine cervical cancer (UCC) is an important public health problem in Chile. Although HPV infection has been established as the main cause of UCC, little is known of its frequency and distribution in our population.

Aim: To determine the presence and frequency of viral genotypes in uterine cervical specimens with preneoplastic and neoplastic lesions.

Material and methods: Two nested consensus PCRs followed by identification of amplified product by dot-blot hybridization and restriction fragment length polymorphism (RFLP) were used to analyze 175 biopsies.

Results: Detection of HPV was 40% in cases without histological lesion, 88% in low grade lesions, 89% in high grade lesions (HGL) and 93.5% in invasive carcinoma. Of all HPV positive cases, 89.5% were classified as high risk and only a 4.9% of HPV cases were of low risk type. Six percent of cases had multiple infections. Distribution of viral genotypes according to RFLP was: HPV33 (25.3%), 16 (18.7%), 52 (13.3%), 31 (12%), 35 (6.6%), 18 (2.7%).

Conclusions: Most HPV found in biopsies with HGL and UCC were of high risk genotype. The elevated presence of high risk HPV in patients without cervical lesions may be a factor that explains the high percentage of UCC cases in our region. Most common viral types were: HPV16, 31, 33 and 52. Viral detection and typing may provide valuable information for patient selection and follow up and for allocation of resources.