Detection and typing of papillomavirus DNA in formaldehyde-fixed paraffin-embedded tissue

Clinical specimens from nine patients with papillomatosis of the vocal cords and three patients with vocal cord polyps were evaluated for the presence of human papillomavirus (HPV) DNA using two complementary molecular hybridization techniques. In one method, involving polymerase chain reaction (PCR) amplification, HPV DNA sequences were replicated in vitro from tissue DNA extracted from paraffin sections prior to hybridization. Polymerase chain reaction amplification was compared with the standard method of Southern blot hybridization. Results of the two techniques for all nine laryngeal papillomas agreed completely: five patients harbored HPV type 6 and four HPV type 11. Both PCR amplification and Southern blot hybridization found two of the three polyps to be free of HPV infection, while PCR detected HPV type 18 in one polyp specimen that was reported negative by Southern blot hybridization, suggesting a greater sensitivity of PCR. Our results demonstrate that PCR amplification is as reliable and at least as sensitive as Southern blot hybridization. Moreover the PCR technique opens the way to the undertaking of a whole variety of retrospective studies using formaldehyde-fixed paraffin-embedded tissues.