The incidence of advanced prostate cancer in the United States “continues” to increase every year for 5 years after the United States Prevention Service Task Force (USPSTF) controversially suggested in 2012 opposes prostate specific antigen (PSA) screening in men of all ages, new research shows.
But a biostatistics expert not involved in the study said the USPSTF recommendations were not entirely to blame because “you need 5 to 7 years of minimum time lag to influence PSA screening,” and suggested that other factors come into play.
In the new study, Ahmedin Jemal, DVM, PhD, from the American Cancer Society and colleagues reported that for the 2012-2016 period there was a statistically significant increase every year in the incidence of regional stage disease (with an absolute 11% per year) and in distant stage disease ( absolute 5% per year).
At the same time, there is an annual decrease in the incidence of local prostate cancer in men 50 years or more.
The new study is the first to report data until the end of 2016.
Two trends – an increase in advanced cancer and a decrease in early cancer – have been occurring for 10 years, more or less, but with a steady and sharp increase in advanced disease from 2010 to 2012, the findings show.
“This data illustrates the trade-off between higher screening rates and more early diagnosis of disease (possible overdiagnosis and overtreatment) and lower screening rates and more (possibly fatal) end-stage disease,” comment the authors.
That research published online today at Journal of the National Cancer Institute.
Several previous studies have reported changes in the pattern of events following the USPSTF recommendations on PSA screening for men aged 75 or over in 2008 and all men in 2012, but the data is not later than 2015.
“We have seen clues about this change in recent years and now we have further confirmation,” said Ahmad Shabsigh, MD, urological oncologist at Ohio State University Comprehensive Cancer Center, who were asked for independent comments.
“What is surprising is that every year,” Shabsigh said Medscape Medical NewsRefers to an increased incidence of advanced cancer.
“Seeing it clearly in this study is sad,” Shabsigh added.
The study period began in 2005, but did not cover the years after 2018, when the USPSTF recommendations changed again and suggested that “individual” screening for men 55-69, and that men aged 70 years and over should be issued.
US cancer registration data, which are the source of current research, are not yet available to assess the impact of this latest change.
End with Vision?
There has been a decline in the proportion of men who underwent PSA testing in the US in recent years, the study’s authors point out.
The rate of routine PSA testing among men aged 50 and older decreased from 40.6% in 2008 to 38.3% in 2010, and fell to 31.5% in 2013, a percentage held again in 2015, per survey data reported nationally alone.
The study authors say that the cause of the increase in advanced cancer is uncertain because of the descriptive nature of their study.
But Andrew Vickers, PhD, a biostatistician at the Sloan Kettering Cancer Center Memorial in New York City, said the rise in advanced cancer and the decline in early stage cancer reported in this study was “suggestive of a causal relationship” and “screening”. effect.”
Vickers argues that there are “a number of trends that appear together at the end [2000s] influence [PSA] filtering.”
For example, two randomized clinical trials for PSA screening first reported “unfavorable” results in 2009, which were during the period covered by this study, and reduced enthusiasm for screening.
European Random Screening Study for Prostate cancer (ERSPC) and US-based Prostate, Lung, Colorectal and Ovarian (AS) Cancer Screening Tests reported little or no effect on mortality, the main results of the trial.
It would surprise me if we had reached the lowest point …
Medscape Medical News asking Vickers to speculate about how long the incidence of advanced prostate cancer will continue to increase in the United States.
“It will surprise me if we make it to the lowest point [and reached peak increases in advanced cancers] or if we have more time to go, “he said.” My prediction is that if nothing has changed we might see some further improvement in [the incidence of] advanced disease. “
What needs to change? Vickers marks the list of “golden rules”.
First, doctors need to get approval for all PSA tests.
Second, PSA tests should not be given to older men “who will not benefit,” such as men 75 years and older with comorbidities such as heart disease.
Third, PSA testing must be restricted to younger men.
Fourth, doctors need to be more restrictive about biopsies. “In the past if you had a high PSA, you would get a biopsy,” he said, adding that this approach produced many invasive tests in men with low-grade disease. By using additional tests such as 4Kscore or Prostate Health Index or MRI, doctors can limit biopsies in men with a higher chance of developing high-level cancer. Vickers admitted there was a conflict of interest at this point, because he was the patent holder of 4Kscore.
Fifth, do not treat men who are highly unlikely to benefit, especially men with Gleason grade 6 disease. Use active supervision for these people, he said. “By using our existing knowledge, I believe we can truly change the hazard-to-benefit ratio from PSA screening. We will drastically reduce overdiagnosis and overtreatment,” he said.
In addition, Vickers believes that urologists need to educate local internists and general practitioners and recognize that screening and subsequent treatment “are done wrong for a long time.” At the same time, urologists must explain that patients will not be biopsied “unless there is very good reason to believe that they have a high risk of high-level disease.”
Vickers concluded: “We can reduce the danger and maintain the benefits of screening.”
This research was supported by the American Cancer Society. Jemal and Shabsigh do not disclose relevant financial relationships. Vickers states that he is the patent holder of 4Kscore.
Journal of the National Cancer Institute. Published online May 20, 2020. Abstract
For more on Medscape Oncology, join us at Indonesia and Facebook