Case 143. HPV-16 infection (severe dysplasia) (38 y-o F)
    Cervical smear and biopsy from a sexually active woman with colposcopic abnormality    
Key words : 
human papillomavirus, severe dysplasia, cervical intraepithelial neoplasia-3    
sexually transmitted infection
Clusters of dyskaryotic cells of parabasal type are observed in a Papanicolaou-stained preparation.   Restaining of the bleached pap smear (in situ hybridization for HPV, type 16 genome) shows dot-like reactivity in the nucleus of some dyskaryotic cells.
Cervical biopsy discloses dysplastic squamous mucosa with mild and focal surface differentiation (HE).   A few superficially located atypical cells reveal dot-like signals for HPV, type 16 genome in the nucleus (non-isotopic in situ hybridization).
HPV, type 16 genome-positive location in severe dysplasia ultrastructurally corresponds to part of chromatin, indicative of the integration of the oncogenic viral DNA into host cell DNA (pre-embedding method for in situ hybridization using a paraffin section).