1. Samson, Kurt

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A large analysis of cancer data has found that the cervical cancer rate has edged lower over the last 17 years, especially since the introduction of human papillomavirus (HPV) screening and vaccination. However, the incidence of other HPV-associated cancers is rising and could soon surpass cervical cancer, a researcher told a press briefing held in advance of the 2021 ASCO Annual Meeting (Abstract 104).

HPV-Related Cancers.... - Click to enlarge in new windowHPV-Related Cancers. HPV-Related Cancers

Between 2001 and 2017, the incidence of cervical cancer decreased annually by 1 percent, and accounted for 52 percent of all HPV-related cancers in the U.S.


"It is likely that the significant decrease in cervical cancer incidence results from clear guidelines for cervical cancer screening and may also reflect promotion and acceptance of vaccination, particularly in younger women," said lead author Cheng-I Liao, MD, of Kaohsiung Veterans General Hospital, in Kaohsiung, Taiwan.


However, at the same time, the incidence of other HPV-related cancers, for which there is no standardized screening, increased significantly, the investigators found. This is especially true for oropharyngeal, anal, and rectal squamous cell carcinoma, according to the report. If the trajectory continues at this pace, these cancers are projected to surpass cervical cancer within 5 years for certain at-risk groups.


Study Details

The analysis included data on 657,317 individuals from the United States Cancer Statistics program from 2001 to 2017. Incidence trends were calculated for HPV-associated cancers, including oropharyngeal squamous cell carcinoma (SCC), anal and rectal SCC, vulvar SCC, vaginal SCC, cervical carcinoma, and penile SCC.


The scientists also evaluated age-specific cervical cancer incidence for individuals in the age group that ranged from 20 to 24 years. When compared to older cohorts, women in this younger group had a disproportionately greater decrease in the incidence of cervical cancer-4.63 percent per year-the investigators found.


In 2006, the HPV vaccine was first approved for girls and young women ages 9-26 years. In 2011, recommendations for HPV vaccination were extended to boys ages 11-12 years. Today, the vaccine is approved for everyone up to age 45; however, there are no widely followed guidelines for other cancers that are known to be associated with HPV. These include oropharyngeal, vulvar, vaginal, penile, anal, and rectal cancers.


The researchers found that the incidence of HPV-related cancers without standardized screening guidelines dramatically increased in women over the 17-year period. The overall annual increase in incidence of oropharyngeal, anal, rectal, and vulvar cancers among women was 1.3 percent per year.


The prevalence, especially in rates of anal and rectal cancers, is expected to continue to grow and to surpass that of cervical cancer in every age group over 50 by 2025, Liao noted.


The overall annual increase in HPV-related cancers increased by 2.36 percent per year in men, with the greatest increase in the incidence of oropharyngeal cancer. In men, the incidence of oropharyngeal cancer accounted for 81 percent of all HPV-related cancers from 2001 to 2017-a nearly fivefold higher incidence compared to women.


"Without standardized screening, HPV-related cancers, such as oropharyngeal cancers and anal rectal cancers, are increasing," said Liao. "In order to reduce these trends and achieve success comparable to what we're seeing with cervical cancer, we must develop effective screening strategies and determine vaccine efficacy in these patient populations."


Statistically, the overall incidence of HPV-related cancers for women over the 17-year period was 13.68/100,000, of which 52 percent were cervical cancer, or 7.12/100,000 in the year 2017. The incidence of cervical cancer decreased at an annual percent change of 1.03 percent. In contrast, incidence of oropharyngeal cancers rose by 0.77 percent, anal and rectal cancers by 2.75 percent, and vulvar cancers increased by 1.27 percent.


For older women, the incidence of anal and rectal cancer approached that of cervical cancer. In those over 80, the incidence of cervical cancer was 6.95 (annual percentage of change [APC] 2.90%), compared to 6.36 for anal and rectal cancer (1.23% APC). Using a projection model, the incidence of anal and rectal cancer is expected to surpass that of cervical cancer by year 2025 for every age group over 55.


For men, the incidence of all HPV-related cancers was 11.0/100,000 in the year 2017; 81 percent were associated with oropharyngeal cancer.


Those at greatest risk of oropharyngeal cancer were older men ages 65-69 years with an incidence of 36.5/100,000 and annual percent increase of 4.24 percent (p< 0.001). The intersectionality of age and race showed that White men ages 65-69 years had the highest incidence of oropharyngeal at 41.6/100,000.


The researchers next plan to analyze the rates of HPV testing and vaccination from other databases to get additional information.


Commenting on the study, ASCO President Lori J. Pierce, MD, FASTRO, FASCO, said the study provided both good and bad news.


"The decrease in cervical cancer is welcome news and may reflect intensive efforts to screen and vaccinate patients at risk," she noted. "Clearly, this study shows that we still have a great deal of work to do in order to reverse the increasing incidence rates of other HPV-related cancers. Further resources and research should be conducted to address the lack of screening or vaccination in these preventable cancers."


Kurt Samson is a contributing writer.