Change in Specimen Requirements for High-Risk HPV Testing
Since 2003, Mayo Medical Laboratories has performed #83344 Human Papillomavirus (HPV) Detection-High Risk Types using the Qiagen Digene Hybrid Capture 2 (hc2) High-Risk HPV DNA Test kit–a nucleic acid hybridization assay with signal amplification that utilizes microplate chemiluminescent detection. For many years, this assay was the only US Food and Drug Administration (FDA)-approved method for the detection of HPV DNA of high-risk genotypes associated with the development of cervical cancer. The hc2 assay is well established in the laboratory and the clinical setting and is routinely used for optimal diagnosis and treatment of cervical disease for women at Mayo Clinic and those in the care of Mayo Medical Laboratories clients.
Recently, we instituted an improved method of DNA extraction for detection of high-risk HPV from female cervical and vaginal samples using the hc2 method. The new extraction method necessitates the following changes to our sample requirements:
ThinPrep: Submit 8 mL of sample for testing. This is a 2 mL increase from our previous volume requirements, but falls well within the amount routinely received by our laboratory for testing. If the full amount is not submitted, there may be insufficient volume for complete testing. In our experience, if only 2.5 mL of sample are received, approximately 3% will be reported as “Equivocal”, whereas a sample volume of 6 mL will result in “Equivocal” results in <1% of samples. An 8 mL sample allows for complete testing in the majority of cases.
SurePath: Submit the residual enriched cell pellet from the BD SurePath Cell Enrichment Process with 2 mL of added SurePath media. Although this is a change from the specimen that we currently accept, the enriched cell pellet provides the highest yield of HPV DNA. We will no longer accept nonenriched samples.
Digene Specimen Transport Media (STM) with Brush: As of March 15, 2010, we will no longer accept STM specimens for HPV nucleic acid testing. This media is not supported by automated extraction platforms. Instead, we encourage clients to submit a pre- or post-cytology specimen in ThinPrep or SurePath media as directed above. Clients collecting anal samples in STM media may send testing to Mayo Medical Laboratories for referral to our partner reference laboratory.
HPV screening is only available for cervical and vaginal specimens. Other specimen types are not acceptable for this purpose.