HPV DNA testing is better than cytology alone in preventing cervical cancer or detecting it early on for women over thirty, researchers reported in The Lancet Oncology. The authors explained, after reporting on the POBASCAM trial, that they now have compelling evidence in favour of routine HPV testing in national screening programs.

In an Accompanying Comment, Hormuzd Katki and Nicolas Wentzensen wrote:

“POBASCAM reinforces findings from cohort studies, clinical trials, and routine clinical practice by providing overwhelming evidence of the benefits of inclusion of HPV testing in screening programmes”

Experts already knew that HPV testing is better than cytology at identifying precancerous high-grade cervical lesions. However, before this study, nobody could be sure which method of testing was best over a 5-year screening interval.

Chris Meijer and team from the VU University Medical Centre, Amsterdam, carried out the POBASCAM trial, involving 45,000 females aged between 29 and 56 years. All of them attended routine cervical screening in the Netherlands.

The researchers wanted to find out whether HPV testing was associated with fewer high-grade lesions and cervical cancer during the second round of screening, because the first round had detected and treated the lesions. They also wanted to determine what the best age might be to start HIV testing.

Initially, the participants were selected at random to receive:

  • HPV DNA testing plus cytology, or
  • Cytology alone

Five years later, all of them had a second screening which involved both HPV and cytology testing.

The researchers found that:

  • During the first screening – Considerably more cancer precursors were identified through HPV testing compared to cytology alone
  • During the second screening (five years later) – those in the HPV testing group had considerably fewer women had CIN grade 3 or worse lesions and cervical cancer than the ones who had been in the cytology alone group

The authors explained:

“Implementation of HPV DNA testing in cervical screening leads to earlier detection of clinically relevant CIN grade 2 or worse, which when adequately treated, improves protection against CIN grade 3 or worse and cervical cancer.”

Better CIN3+ in the HPV groups was mainly due to better early detection of high-grade lesions caused by HPV16. The authors say their findings indicate that HPV testing will most likely eventually reduce death rates as well as the number of cancer-related illness.

HPV testing does not appear to be linked to over-diagnosing of regressive CIN2+ lesions in younger females either, the authors added. When they combined the data from both screening rounds, the accumulated detection of CIN2+ and CIN3+ were the same among females aged 29-33 and those aged over 33.

The authors wrote:

“Our results . . . lend support to the implementation of HPV DNA testing in programmed cervical screening starting at age 30 years.”

The authors of the Accompanying Comment wrote:

“The POBASCAM trial shows that 5 year screening intervals are safe, and that conservative management of HPV-positive women can control excess CIN grade 2 or 3 while preventing cervical cancer. However, how the POBASCAM protocol would perform in other populations that have different baseline cancer rates, compliance, and management infrastructure, is unclear.”

Written by Christian Nordqvist