Comparison of FFPE histological versus LBP cytological samples for HPV detection and typing in cervical carcinoma

Human papillomavirus (HPV) infection is closely associated with cervical cancer. This study analyzed HPV genotype prevalence in 75 cases of formalin-fixed paraffin embedded (FFPE) tissue samples from patients diagnosed with cervical cancer. Genotype prevalence was assessed using Reverse Blot Assay (REBA) and quantitative polymerase chain reaction (qPCR), which target the HPV L1 and HPV E6/E7 genes, respectively. HPV DNA chip tests were also performed using liquid based preparation (LBP) cytological samples from the same patients who provided the FFPE histological samples. We observed a slight difference in HPV genotype distribution as assessed by DNA chip versus REBA. One possible explanation for this difference is that normal regions could be mixed with lesion regions when cytological samples are extracted from each patient with cancer. For the detection of moderate dysplasia, the main target of diagnosis, this difference is anticipated to be greater. We also made several unexpected observations. For example, HPV multi-infection was not detected. Moreover, the rate of HPV positivity varied radically depending on the cancer origin, e.g. squamous cell carcinoma versus adenocarcinoma. Our results imply that it is important to determine whether cytological specimens are suitable for HPV genotyping analysis and cervical cancer diagnosis. Future research on the mechanisms underlying cervical cancer pathogenesis is also necessary.