Efficient treatment of paraffin-embedded cervical tissue for HPV DNA testing by HC-II and PCR assays.

ABSTRACT

BACKGROUND AND OBJECTIVES: High-risk human papillomaviruses (HR-HPVs) are the primary cause of cervical cancer. In order to meet with clinical requirements, a direct capture test with signal amplification (HC-II), able to detect the 13 prevalent HR-HPVs, has been developed and validated for cytological specimens. STUDY DESIGN: the use of HC-II assay with formaldehyde-fixed paraffin-embedded cervical biopsies, for retrospective studies or to support histological findings, was investigated by analysing three different sample treatments. The efficacy of this test was compared with a reference PCR-ELISA, using MY09/11 and GP5+/6+ consensus primers and the use of a single extraction method for both HC-II and PCR-ELISA assays was validated. RESULTS: protease treatment of dewaxed biopsy sections allowed an optimal performance of HC-II and has also been validated for PCR-ELISA. Overall, on the analysis of 50 cervical samples HC-II and PCR-ELISA assays showed a high concordance (K=0.80). Compared with PCR-ELISA, the HC-II had a sensitivity of 86.4% and a specificity of 92.9%. The results showed that short amplimers are necessary for a sensitive PCR-ELISA from formaldehyde-fixed paraffin-embedded biopsies, while HC-II showed a relatively low sensitivity for HPV18 within the HR probe pool. CONCLUSIONS: HC-II can be a valid tool for the diagnosis of HPV infection in biopsy material. The possibility to use the same specimen preparation material for both HC-II and PCR-ELISA allows HC-II positive specimens to be further processed by PCR-ELISA if specific genotyping is needed.