Signal-amplified colorimetric in situ hybridization for assessment of human papillomavirus infection in cervical lesions

Detection and typing of human papillomavirus (HPV) infection may have a maj or impact in cervical-screening and fallow-up. In this study various commer cially available techniques for the detection of HPV were evaluated. HBV-st atus was determined in 86 samples of cervical cancer by PCR and direct sequ encing, catalyzed signal amplified colorimetric DNA in situ hybridization ( CSAC- ISH) (GenPoint system, DAKO), immunohistochemistry CMC) and in 12 sel ected cases also by conventional, non-amplified ISH, Twenty-one samples of cervical intraepithelial neoplasias grade III (CIN III) were investigated b y CSAC-ISH, conventional ISH and by IHC, in corresponding PAP smears HPV-de tection and typing was performed by CSAC-ISH and Hybrid Capture test II (HC ), In additional 20 PAP smears HPV typing was performed using HC and a nave l immunocytochemical system for HPV detection and-typing. CSAC-ISH showed g ood correlation with PCR analysis in cervical cancers: In 87% of PCR positi ve cases, HPV infection was also detected by CSAC- ISH (66/76). HPV 16 was detected in 75% of PCR-positive cases (44/59), HPV 18 in 71% of PCR positiv e cases (5/7). CSAC-ISH detected HPV 31 in only 29% of PCR positive cases ( 2/7), and HPV 33 in 64% of PCR-positive cases (23/36), Nevertheless, CSAC-I SH- false negative cases for MPV 31 or 33 were nearly always combined infec tions with other HPV types, which were detectable by CSAC-ISH in most cases . CSAC-ISH revealed HPV infection in 20 of 21 HC-positive cervical smears, while in corresponding biopsies (CIN III) CSAC-ISH detected 100% of HBV inf ections. Conventional, nonamplified ISH showed significantly lower sensitiv ity compared with CSAC-ISH, and immunocyto- and -histochemistry were of ver y low sensitivity for detection of HPV. CSAC-ISH is an easy-to-handle metho d for detection and typing of cervical HPV infection, and shows sufficient sensitivity for clinical practice.