On Jul. 8, 2020, a Health Trends study from researchers at Quest Diagnostics and the University of Pittsburgh Medical Center provided new evidence that the HPV screening test is significantly less likely to detect cervical cancer and precancer than cotesting, a method which combines HPV and Pap (Papanicolaou test by liquid based cytology) testing using the same specimen.

The study is significant because it is the largest to date to assess the performance of guideline-recommended cervical cancer screening methods in a diverse population of American women in real-world care settings. It reveals stark differences in the performance of the various recommended methods in detecting cancer and precancers in women 30 years of age and older.

Published online in the American Journal of Clinical Pathology, the peer-reviewed study assesses sensitivity rates of HPV alone, Pap alone and cotesting (HPV and Pap testing together) in detecting cancer and precancer of the cervix in nearly 19 million de-identified cotest results performed by Quest Diagnostics on behalf of 13.6 million women in the United States from 2010 to 2018. Of these cases, 1,259 were diagnosed with cervical cancer – twice the number of diagnosed cancer cases as the next largest study.

HPV testing identifies the genetic material of the human papillomavirus virus, which can cause cervical cancer, while Pap identifies cellular changes on the cervix that may be or become cancer. The United States Preventive Services Task Force (USPSTF) recommends screening in women 30-65 years of age every three years with Pap, every five years with cotesting or every five years with primary HPV testing.

Among the key findings:

• HPV and Pap testing alone fails to detect twice as many women who develop cervical cancer as cotesting. Of 1,615 cotests taken at any time prior to a cancer diagnosis, 86.9 percent were positive by cotesting, a non-detection rate (also known as false negative) of about 13.1 percent. By comparison, Pap and HPV testing alone had non-detection rates nearly twice as high: Pap at 26.4 percent and HPV at 28.4 percent. 
   
• Cotesting detected significantly more women who developed biopsy-confirmed adenocarcinomas, a typically aggressive form of cervical cancer, identifying 82.3 percent of this cancer compared to only 61.2 percent by HPV and 59.7 percent by Pap.
   
• HPV testing fails to identify one in five women who develop cancer when performed within a year of cancer diagnosis. Among women screened within one year of a cancer diagnosis, the non-detection rate for HPV testing alone was 22.5 percent, nearly 1.5 times higher than Pap (14.9%) and four times higher than cotesting (5.9%).
   
• Cotesting detected more women who developed biopsy-confirmed precancers than HPV or Pap alone, identifying 95.6 percent of these precancers, compared to 92.6 percent by HPV and 77.9 percent by Pap.

According to a report published in January 2020 by the American Cancer Society, cervical cancer is the second leading cause of cancer death nationally in women 20-39 years of age, causing 10 premature deaths per week in this age group.