乌鸦传媒

Access to vaccination and screening appeared to provide a clear benefit in the case of cervical and prostate cancers, two observational studies found.

While the incidence of human papillomavirus (HPV)-associated cancers has continued to increase since 2001, cervical cancer rates have decreased by 1% annually from 2001 to 2017, reported Cheng-I Liao, MD, of Kaohsiung Veterans General Hospital in Taiwan.

"In young women, cervical carcinoma is decreasing consistently with screening, and possibly vaccination, at the population level," he said.

In the other study by Edmund Qiao, BS, a medical student at the University of California San Diego, and colleagues, it was found that younger African-American men who undergo frequent prostate cancer screening have a lower risk of metastasis at the time of cancer diagnosis, as well as fatal disease.

These studies were presented at a press briefing in advance of the virtual American Society of Clinical Oncology (ASCO) annual meeting.

Cervical Cancer Rates Are Dropping

Liao and colleagues used data obtained from the U.S. Cancer Statistics program from 2001 to 2017. They found that there were a total of 657,317 cases of HPV-associated cancers (60% women, 40% men). Of the cases in women, the majority (52%) were cervical cancers, while oropharyngeal squamous cell carcinoma made up 80% of the cancers in men.

During that time period, the incidence of all HPV-associated cancers increased annually by 2.35% (2.71% among men and 0.77% among women). However, the incidence of cervical cancer decreased annually by 1.03%.

When Liao and colleagues evaluated cervical cancer incidence by age, they found that women ages 20-24 had a much higher decrease in incidence -- 4.63% per year -- compared with women in older cohorts. Considering that an HPV vaccine was approved in 2006 for girls and young women ages 9-26, the researchers suggested that this decrease indicates a potential effect from vaccination.

They also observed that the incidence of HPV-related cancers without standardized screening -- such as oropharyngeal, anal, and rectal squamous cell carcinoma -- increased over the study period, and projected it will surpass cervical cancer within 5 years for certain patient groups.

"This is an interesting observational study that shows we are probably getting some benefit from the HPV vaccine," commented ASCO Chief Medical Officer and Executive Vice President Julie Gralow, MD, of the University of Washington in Seattle.

However, Gralow pointed out that while cervical cancer rates may be declining in the U.S., incidence and mortality rates are exceedingly high in other parts of the world.

"In regions with certain low- and middle-income populations, cervical cancer actually has a higher rate of incidence and mortality than breast cancer," she said, adding that the is making a major push to eliminate cervical cancer as a public health problem, with a campaign focusing on a combination of screening, vaccination, and detection of cancer precursors.

PSA Screening Improves Outcomes in Younger Black Men

Qiao and colleagues found that an increased intensity of prostate-specific antigen (PSA) screening among younger African-American men resulted in a decreased risk of having a Gleason score ≥8, PSA >20 ng/mL, and metastatic disease at diagnosis, as well as prostate cancer-specific mortality.

"Taken together, these results suggest that PSA screening may improve cancer outcomes for young African-American men, although the results of this study are just one step in addressing all the other racial disparities that still exist in prostate cancer," said Qiao.

The researchers identified 4,276 African-American men ages 40-55 within the Veterans Health Administration who were diagnosed with prostate cancer from 2004 to 2017.

The entire patient cohort averaged 1.9 PSA screening tests at time of diagnosis. They were stratified into the high screening group (an average of 3.0 previous PSA tests) or low screening group (average of 0.5 previous PSA tests).

At the time of diagnosis:

• 10.7% of men in the high screening group had a Gleason score ≥8 versus 15.3% of men in the low screening group
• 7.2% of men in the high screening group had a PSA >20 ng/mL compared with 16.3% in the low screening group
• 1.4% of men in the high screening group had metastatic disease compared with 4.2% in the low screening group

They determined that PSA screening intensity at the time of diagnosis was associated with a 40% reduced risk of metastatic disease and a 25% reduced risk of prostate cancer-specific mortality.

"I think this provides information to aid in the discussion of risks and benefits [of PSA screening] in this population," said Gralow. The problem, she suggested, is that even if primary care providers and other practitioners are ready to engage in this discussion, "a lot of these healthy young men aren't getting primary care in the first place."

"So this isn't just a question of educating the primary care community in order to inform their discussions," she noted, "but also one of broader community awareness so that younger men will seek out healthcare providers to talk about this."