More Options for Cervical Cancer Screening

Laboratorians  may see a rise in the volume of human papillomavirus (HPV) tests to screen for  cervical cancer. In revised guidelines, the United States Preventive Services  Task Force (USPSTF) for the first time is recommending  standalone high-risk (hrHPV) testing?as  one of several options for women ages 30 to 65 years.  The task force in 2012  broke new ground by offering a cotesting option with Pap and HPV every 5 years  for women in this age group. The 2018 update went a step further, proposing  multiple options that include hrHPV every 5 years as well as two previous  recommendations: Pap every 3 years or cotesting every 5 years. All of these  options are similarly effective in detecting cervical cancer, according to task  force member Carol Mangione, MD, MSPH.

Younger  women should continue to get tested with Pap every 3 years. “We determined that  the benefits of continuing Pap smears every three years for women ages 21-29  were greater than for switching to HPV testing alone because most HPV infections  in this age group will resolve spontaneously,” Mangione explained  to CLN  Stat.   For some women, the Pap will continue to be the preferable screening option,  depending on individual circumstances. “Women should discuss with their doctor  which testing strategy is best for them,” she said.

The  task force published?its  recommendations in the Journal  of the American Medical Association (JAMA) following  an extensive review?of  clinical and cohort studies that compared various screening combinations for  cytology and hrHPV, and a decision  analysis?that  evaluated screening intervals, harms and benefits of different screening  methods, and optimal ages and intervals for screening.

Investigators  defined benefit as the years of life gained from cervical cancer prevention,  whereas harm was defined as the number of invasive tests and procedures  performed, Lee A. Learman, MD, PhD, professor of obstetrics and gynecology at  Florida Atlantic University’s Schmidt College of Medicine, and author of a  related editorial?on  the USPSTF’s recommendations, told CLN  Stat.

Four  studies identified in the review found that primary hrHPV testing detected  higher rates of stage 3 (or worse) cervical intraepithelial neoplasia compared  with the standalone Pap test in the first round of testing. In comparing the  Pap, hrHPV and cotesting methods, the latter two methods were associated with  higher colposcopy and false-positive rates, “which could lead to more treatments  with potential harms,” authors of the review cautioned.

Overall,  the clinical literature suggests that hrHPV is a more sensitive test than Pap  testing in identifying both stage 2 and 3 cancers, the task force indicated in  its recommendation statement. “The USPSTF concludes with high certainty that the  benefits of screening every 3 years with cytology alone, every 5 years with  hrHPV testing alone, or every 5 years with both tests (cotesting) in women aged  30 to 65 years outweigh the harms,” the task force concluded in its  recommendations statement. The anticipation is hrHPV testing every 5 years for  women in the 30 to 65 age cohort could reduce cervical cancer mortality from  8.34 to 0.29 deaths per 1,000 women.

In  other recommendations, the task force discouraged screening in women older than  age 65 with a previous history of screening, in women younger than 21, and in  women without a cervix, due to evidence suggesting that it would offer little to  no benefit.

USPSTF’s  latest recommendations represent the growing credibility of HPV testing as a  screening tool for cervical cancer. Various  studies?   have reported on the test’s superiority to Pap testing as a more sensitive and  less expensive alternative. Most recently, a study?published  in the JAMA found  that HPV testing was more efficient than Pap testing in identifying  precancers.

The  2018 guidelines “continue the trend of decreasing participant burden by  lengthening screening intervals, making the ‘annual Pap’ a historical artifact,”  Learman and Francisco A. R. Garcia, MD, MPH, wrote in the related  editorial.

HPV  testing every 5 years is an attractive option for patients who want to avoid  pelvic exams and Pap smears, Learman told CLN  Stat.  That said, it will take a long while before HPV testing replaces cervical  cytology, if ever. “The Pap test is well-known and accepted by patients and  women’s healthcare providers, and there would need to be powerful incentives to  move away from it,” he observed. “Switching from Pap tests annually to every  three years has been the USPSTF recommendation since 2012, but patient and  provider preferences have been hard to change. I expect the same phenomenon will  delay implementation of primary HPV screening every 5 years.” 

The  editorialists underscored the need to expand access to these screening tools to  indigent communities that receive sporadic and fragmented care at safety net  healthcare facilities. “For the public health planner, the more inclusive  screening menu provides a greater range of options creating more opportunities  to tailor approaches to target populations,” they wrote. In the 2018 guidelines,  the task force called for more research to improve access to screening and  treatment across different populations and reduce disparities.

https://www.aacc.org/publications/cln/cln-stat/2018/september/20/more-options-for-cervical-cancer-screening