Human papillomavirus genotype distribution in cervical samples collected in routine clinical practice at the Nantes University Hospital, France

Abstract

Objective: The objective was to assess the human papillomavirus (HPV) overall and type-specific prevalence in smears collected during routine clinical practice.

Design: HPV genotyping and smears were performed independently between 2000 and 2006 for routine clinical follow-up (primary screening and follow-up) in the University Hospital of Nantes, France.

Population: All women with a cytological sample collected no more than 12 months before HPV genotyping were included.

Methods: PCR was performed with MY09/MY11 primers and genotyping by sequencing PCR product.

Main outcome measures: Overall and genotype-specific HPV prevalence were assessed according to cytological diagnosis.

Results: A total of 1,255 women were included (mean age 37.5 years). The proportion of high-risk (HR) HPV positive samples increased according to cytological diagnosis severity from 8% in normal specimens to 21% in atypical squamous cells of undetermined significance, 49% in low-grade squamous intraepithelial lesion and 75% in high-grade squamous intraepithelial lesion (HSIL) (p < 0.001). Among 980 women with normal cytology, the overall HPV prevalence varied according to age from 44% below 20 years to about 10% above 35 years (p < 0.001). The most prevalent HPV genotype in all cytological diagnoses was HPV 16. HPV 53 appeared as the second most common genotype in normal cytological samples (10.9% of HPV positive samples) but its prevalence decreased in HSIL to less than 4%.

Conclusion: The proportion of HR HPV positive women increased according to cytological diagnosis severity. HPV 16 appeared as the most commonly encountered genotype even when the diagnosis was normal. Its prevalence increased with diagnosis severity hereby confirming that HPV 16 is more aggressive than other genotypes.

Fig. 1

Inclusion algorithm

Fig. 2

Distribution of high-risk and low-risk HPV genotypes according to age in women with normal cytological diagnosis (n = 980)

Fig. 3

Prevalence of most frequently encountered HPV genotypes in cervical samples with normal cytological diagnosis (a), ASCUS (b), LSIL (c) and HSIL (d). Red bars indicate high-risk genotypes, blue bars low-risk genotypes. Prevalence is given as the proportion of each specific HPV genotype among HPV positive samples

Fig. 4

Prevalence of most frequently encountered HPV genotypes in cervical samples with normal histological diagnosis (a), CIN1 (b), CIN2 (c) and CIN3 (d). Red bars indicate high-risk genotypes, blue bars low-risk genotypes. Prevalence is given as the proportion of each specific HPV genotype among HPV positive samples