Proof-of-concept study may eventually lead to new clinical laboratory urine tests for fast, non-invasive detection of cancer
Here is the latest example of researchers finding useful biomarkers in urine for diagnosing certain cancers. The discovery comes from the University of Michigan Health Rogel Cancer Center, where, in a proof-of-concept study, scientists developed a urine-based test that screens for circulating free DNA (cfDNA) fragments (aka, cell-free DNA) released by tumors in the head and neck. If they confirm these findings, it’s possible the technology could be adapted into a non-invasive clinical laboratory test for selected cancers.
One such cancer is human papillomavirus (HPV) which, though “widely recognized for causing cervical cancer” is “increasingly found to cause cancers in the mouth, throat, and other head and neck regions,” according to a U-M Medical School press release.
The U-M study findings could lead to an early, non-invasive test for the detection of cancer, as compared to traditional urine or blood-based liquid biopsy testing.
“In this study, we provide evidence to support the hypothesis that conventional assays do not detect ultrashort fragments found in urine since they are designed to support longer DNA fragments. Our team used an unconventional approach to develop a urine test for HPV-positive head and neck cancer ctDNA detection,” said Chandan Bhambhani, PhD (above), Research Lab Specialist Intermediate at University of Michigan and co-first author of the study, in a news release. Clinical laboratories may soon have a new urine-based test for detecting cancer. (Photo copyright: LinkedIn.)
According to the researchers, benefits of urine testing include:
Testing with urine is convenient for people who may be unable to access healthcare and phlebotomy services.
Urine has low biohazard risk and may be easily collected in large amounts, compared with blood.
Ongoing collection of urine could make way for TR-ctDNA “kinetics to be used as a high time-resolution biomarker” to monitor patients’ response to treatment.
However, urine, the researchers cautioned, must be analyzed in a different manner if it is to be comparable in efficiency to blood-based ctDNA testing.
“There have been mixed reports on the efficiency of TR-ctDNA detection compared with that of blood ctDNA. A potentially crucial factor for the analysis of TR-ctDNA is knowing the length of TR-ctDNA fragments present in urine, because this affects assay design for optimal sensitivity in TR-ctDNA detection,” the researchers explained.
New Assay Detects Ultrashort DNA Fragments
To complete their study, the U-M researchers developed an ultrashort HPV droplet digital PCR (polymerase chain reaction) assay that enabled detection of TR-ctDNA from HPV-associated oropharyngeal squamous cell carcinoma (HPV OPSCC), BioTechniques reported.
The assay was made to target the HPV16 E6 (Human papillomavirus 16) gene and to measure TR-ctDNA in patients with HPV OPSCC, the JCI Insight paper noted.
“The HPV16 E6 gene represents a highly recurrent ctDNA target in the population of patients with HPV OPSCC,” the researchers wrote in JCI Insight, adding:
Targeting ultrashort fragments was essential “for robust TR-ctDNA detection.”
Results in urine with patients with HPV OPSCC was consistent with results from plasma ctDNA.
The test, still in the discovery phase, was mailed to patients who were being treated for the disease and who reside within 100 miles of Ann Arbor, Mich. They returned urine samples for testing at the U-M lab and to get insights into possible post-treatment needs.
“Using longitudinal urine samples from a small case series, we showed proof of concept for early detection of cancer recurrence. Thus, our results indicate that by targeting ultrashort DNA fragments, TR-ctDNA becomes a viable approach for HPV OPSCC detection and potentially for cancer recurrence monitoring after treatment,” the authors wrote.
Further Studies, Possible Test Expansion
HPV infection—and especially HPV type 16—is a growing risk factor for oropharyngeal cancers, according to the National Cancer Institute.
The U-M Rogel Cancer Center scientists plan more studies to leverage the information urine may carry about an individual’s health. The researchers intend to expand the scope of their new test to other cancers including breast cancer and acute myeloid leukemia.
“The test that has been developed has detected cancer far earlier than would typically happen based on clinical imaging. As such, these promising results have given us the confidence to broaden the scope of this study, seeking to expanding distribution even further,” said J. Chad Brenner, PhD, Associate Professor of Otolaryngology-Head and Neck Surgery, U-M Medicine, and co-senior author of the study, in the news release.
The University of Michigan Health study exemplifies scientists’ commitment to new categories of biomarkers that can be used for medical laboratory tests and prescription drugs. And by focusing on urine, the researchers made it possible for patients to collect specimens themselves and send them to the medical laboratory for analysis and reporting.
Lack of regular clinical laboratory screenings in this age group at least partially to blame, researchers say
While cervical cancer rates have seen a 50-year decline overall, that trend is shifting among 30- to 40 year-olds who have experienced a near 2% increase from 2012-2019. This finding comes from a 2024 American Cancer Society (ACS) report that is eyeing the timeline of the human papillomavirus (HPV) vaccines and the lack of clinical laboratory cancer screenings as possible contributors to this new trend.
Though a 2% increase is significant, the study, which was published in CA: ACancer Journal for Clinicians, titled “Cancer Statistics, 2024,” noted that these cancers were “mostly early, curable tumors,” epidemiologist Ahmedin Jemal DVM, PhD, Senior Vice President Surveillance and Health Equity Science at ACS, and senior author of the new report, told NBC News.
To understand how the increase in cancer rates impacts this age group, consider the numbers: “About 13,800 American women are diagnosed with cervical cancer each year and 4,360 die from the disease,” NBC reported.
US vaccination programs for youths have lagged behind nations that have embraced HPV vaccination to positive results.
Australia, for example, has vaccinated a high proportion of its youth since the vaccine was first released in 2006. In 2023, the nation created its National Strategy for the Elimination of Cervical Cancer in Australia program and expects cervical cancer to be fully eliminated there by 2035.
For lab professionals, this demonstrates how new technologies like the HPV test and vaccine can alter how individuals are screened for diseases, and how vaccines can reduce and even eliminate diseases that were once common.
“We need to make sure we are not forgetting about that generation that was a little too old for HPV vaccination,” Jennifer Spencer, PhD (above), Assistant Professor, Department of Population Health and Department Internal Medicine, Dell Medical School, University of Texas at Austin, told NBC News. “The onus is on the healthcare system to think about who is slipping through the cracks,” she added. Lack of clinical laboratory screenings among the 30-40 age group may be contributing to the increase in cervical cancer rates. (Photo copyright: Dell Medical School.)
Lack of Clinical Laboratory Screenings
Research points to a lag in cervical cancer screenings as a possible cause for the recent rise in cases. Timely screening allows doctors to both identify and remove any worrisome lesions before they become cancerous, Jennifer Spencer, PhD, Assistant Professor of the Department of Population Health, Dell Medical School, University of Texas at Austin, told NBC News.
Screenings for women ages 21-65 have fallen 15% since 2000, according to data from the National Cancer Institute. Also, more than half of women with cervical cancer have “either never been screened or haven’t been screened in the past five years, according to the Centers for Disease Control and Prevention,” NBC reported.
The US Preventative Services Task Force recommends that women 21-29 years of age should receive Pap smears every three years. Women 30-65 years of age should do the same, or every five years with an HPV test or combo test.
Despite a decrease in cervical cancer, 29% of women in their 20s are overdue to get screening, NBC noted. This was the age group most likely to be lagging on getting screened. Spencer says that this delay in screening could explain the resulting increase in cervical cancer among the 30-40 age group.
Causes for Lack in Screenings
Regardless of age group, women who were uninsured, in a rural area, non-white, or identifying as lesbian, bisexual, or gay were also more likely to be overdue on screenings, according to Spencer’s study.
In addition, women who just moved to the United States may have missed their screenings, thus increasing risk, epidemiologist Nicholas Wentzensen, MD, PhD, Deputy Director, Senior Investigator, and Head of the Clinical Epidemiology Unit at the National Cancer Institute, told NBCNews.
Additionally, Spencer found in her research that confusion exists by both patients and doctors on when cervical screening should take place. Some participants in her study did not have screening recommended by their doctors, while others simply did not recognize it was necessary.
“When women in one of Spencer’s studies were asked why they hadn’t been screened recently, they commonly said that they didn’t know they needed to be screened or that a health provider hadn’t recommended it. Only 1% [of] women ages 21 to 29 said they had skipped screening because they had received the HPV shot,” NBC News reported.
A 2022 Journal of American Medicine (JAMA) report also looked at screenings as a possible cause. Those researchers found that “only 73% of women with abnormal screening results received follow-up care,” NBC reported.
“If the increase (in cases) is real, it could be a result of missed screening opportunities at earlier ages, as suggested by the increase in squamous cell carcinoma and localized disease. It may also stem from a decrease in screening at younger ages,” the JAMA study authors wrote.
HPV Vaccine and Cervical Cancer Prevention
The HPV vaccine is another important area of research to be considered. Approved in 2006, HPV vaccines were beneficial because HPV “causes six types of cancer, including cervical cancer,” NBC reported.
Women in their early 20s at that time were the first generation to benefit from HPV vaccines, NBC noted. It may be that they continue to benefit in a decrease in cervical cancer among their cohort.
Countries that have emphasized HPV vaccines and stringent screenings in their cancer prevention efforts are reaping the benefits of that policy.
Though cancer screening and the HPV vaccine are important first steps women should take to prevent cervical cancer, follow-through clinical laboratory testing and diagnosis is crucial, Spencer added. This would include additional testing and treatment for any abnormal results of the cancer screening.
However, according to Spencer, “only 73% of women with abnormal screening results received follow-up care,” NBC reported.
Healthcare policymakers today are emphasizing the need for providers to identify and close gaps in care as a way to improve patient outcomes and help control the cost of care. Women who are overdue for a cervical cancer screening test—whether an HPV test or Pap smear—have this care gap. This creates an opportunity for clinical labs to add value.
Clinical laboratories could be helpful during this period by looking at patient files to note which patients are overdue for screenings and then alerting their doctors. Medical labs also could work directly with doctors to establish a program to reach out to patients. Labs would thus be adding value as well as benefitting patients.
By emphasizing HPV vaccinations while having clinical laboratories continue to perform Pap smears, Australia’s rate of cervical cancer has dropped notably
There is currently a global push to completely eradicate cervical cancer and Australia is leading the way with increased funding. It is also focusing on hard-to-reach and underserved populations. Australia is hoping to be first in the world to accomplish this feat by 2035.
For a number of decades, the Pap smear has been the primary screening tool for cervical cancer, as most pathologists and clinical laboratory managers know. However, today it plays a lesser role due to the effectiveness of HPV (human papillomavirus) diagnostic testing, which was put into cervical cancer screening guidelines in 2004.
Then came the first HPV vaccine in 2006. Australia was one of the first nations to implement HPV vaccination programs. By 2010, Australia was working to vaccinate every child. Now, 14 years later, the pool of adults vaccinated against HPV in that nation is causing the rates of cervical cancer to fall.
That means much less cervical cancer test volume for cytotechnologists and cytopathologists, freeing them up to devote their skills to other diagnostic tests.
As the country continues to funnel resources into hitting a zero cancer status, the additional drive will “connect Australia’s world-leading cervical cancer expertise with governments across the region to get HPV vaccine programs up and running, expand screening and treatment, and build health workforce capacity,” said Australia’s Minister for Foreign Affairs office in a press release.
“Australia has always punched above its weight when it comes to cervical cancer, and now Australia is on track to be the first country in the world to eliminate this deadly disease,” said Hon Ged Kearney, MP, RN (above), Assistant Minister for Health and Aged Care and a member of the government’s House of Representatives, in a press release. “By supporting the Pacific and Southeast Asia region [to] eliminate cervical cancer, we are another step closer to ridding the world of this disease.” Clinical laboratories and cytopathologists may soon see less reliance on Pap smears for screening and a shift toward HPV vaccinations to lower the rate of cervical cancer in the US as well. (Photo copyright: Australian Labor Party.)
90% of eligible people will be vaccinated against HPV (including girls and boys).
70% of eligible people will be screened every five years.
95% of eligible people will receive the best possible treatment for precancer and cancer.
In addition to $48.2 million in funding over four years, the program provides:
On the spot testing of samples in First Nations [aka, First Peoples] communities, allowing immediate follow up.
Support for nurses, First Nations health practitioners, and midwives to request pathology for cervical screening.
Increasing support for GPs to undertake colposcopies.
Helping the Underserved
Reaching a wider audience is a large part of Australia’s focus.
“One of my priorities is to address inequities in our health system. I want to make sure that everyone can get access to screening—and all healthcare—no matter where [they] live,” Kearney added. Among the populations sought are First Nations, LGBTIQA+, disabled individuals, and those living away from large cities.
“$8.3 million has been allocated to implement innovate screening models to support such communities,” the Minister for Foreign Affairs office noted in the press release.
Meeting people where they are, and reaching underserved populations, can make a huge difference, especially considering how cervical cancer affects these people. “First Nations women are almost twice as likely to be diagnosed with cervical cancer and face significant barriers to participating in cervical screening compared to non-indigenous women,” the press release notes.
“These tests allow privacy and help to break down barriers for thousands of people who have never screened—including women who have experienced sexual violence, LGBTIQA+ people, and culturally and linguistically diverse and First Nations communities,” the Minister for Foreign Affairs office stated.
There is hope that the push will cause a great shift to other underserved communities as well.
“A quarter of global cervical cancer cases occur in our region, the Indo-Pacific. Tragically, in the Pacific, women are dying at up to 13 times the rate of women in Australia,” said Penny Wong, Australian Minister for Foreign Affairs, in the press release.
How the US Fares in Cervical Cancer Vaccinations
Australia’s vaccination rates far exceed those in the United States. The US government currently recommends HPV vaccination between the ages of 11-12 years old, though it could be administered starting at age nine.
“HPV vaccination is recommended for all persons through age 26 years who were not adequately vaccinated earlier,” the NIH’s National Cancer Institute (NCI) reports.
For years the standard focus for cervical cancer screening has been on the Pap smear. Data show the US lags behind many countries on the rate of HPV vaccination. NCI data show that, as of 2021, in the US just 58.5% of 13-15 year-olds “had received two or three doses of HPV vaccine as recommended,” NCI reported.
With the US’s standard of care still focused on the Pap smear, patients are beginning their cervical cancer prevention journey at a later age. This is because the preliminary age to get a Pap smear in the US is 21 years old, with follow-up exams every three years, the NCI reported.
Even those in this country who are sexually active are not recommended to get screening earlier than 21.
The NCI recommends HPV testing every five years starting at age 30 until 65, with Pap tests every three years.
Clinical laboratories may soon find that, while the US has been slower to get on board with HPV vaccinations, trends in other nations indicate that this may soon change. The reliance that was once placed on the Pap smears prior to 2000 will likely give way to HPV vaccinations at ages and vaccination rates that mirror programs in countries like Australia—where marked reductions in the rate of cervical cancer demonstrate the effectiveness of a successful HPV vaccination program.
Some experts question the usefulness of Pap testing going forward. But how would cutting back on Pap testing affect clinical laboratory revenue and is it safe for cancer patients?
Recently, a major medical society issued its findings that cervical cancer in the United States has been on a sustained decline for more than a decade and a half. This confirms what cytopathologists and cytotechnologists have watched as the development of new clinical laboratory tests, and the introduction of a vaccine for HPV (human papillomavirus) about 15 years ago, contributed to a reduction in the number of cervical cancer deaths annually here in the United States and in several other nations.
As incidences of cervical cancer declined, so have orders for Pap tests. Thus, clinical laboratory revenues in this area also have declined. This is a change from the 1990s and early 2000s, when Pap tests were the primary screening tool for cervical cancer. About 55 million Pap tests were performed annually during those years and many labs maintained sizeable numbers of cytotechs to perform these tests.
HPV Testing Drove Decreases in Cervical Cancer, Decline in Pap Testing
For at least the past decade, there are pathologists, cytotechnologists, and medical laboratory scientists who graduated from their training programs and began working in labs unaware that, since the 1990s, conventional Pap testing as a major source of test referrals and revenue for clinical laboratories and pathology groups has been on the decline.
What is the reason for the decline? Advances in several areas of medicine, implemented over the past 25 years, have greatly altered how we screen for cervical cancer today. And, in a stepwise fashion, the HPV test and HPV vaccine steadily reduced the role of Pap tests as a primary screening tool.
HPV, a common sexually-transmitted virus, is linked to not only cervical cancer, but also cancers of the vulva, vagina, penis, and anus, according to the Centers for Disease Control and Prevention (CDC) data, which recorded 43 million HPV infections in the US in 2018.
“It is likely that the significant decrease in cervical cancer incidence (in the US) results from clear guidelines for cervical cancer screening and may also reflect promotion and acceptance of [HPV] vaccination, particularly in younger women,” said the ASCO study’s lead author Cheng-I Liao, MD (above), in a news release. Liao is affiliated with Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan. (Photo copyright: Healio.)
Cervical Cancer Down, But Other HPV Cancers Up
Though cervical cancer incidence is down, other HPV-related cancers may need additional screening standards to head off rising cancer cases, the ASCO study suggests.
To conduct their study, the ASCO researchers analyzed data for 657,317 people in the US Cancer Statistics (USCS) program from 2001 to 2017. The researchers reported their findings at the 2021 ASCO Annual Meeting held online in June. They include:
Cervical cancer incidence rate decreased each year by 1.03% annually over 16 years.
In the 20 to 24 age group, a “disproportionately higher decrease” of 4.6% per year in cervical cancer incidence rate suggested “potential effect of vaccinations.”
Without screenings, HPV-related cancers incidence increased in women over 16 years.
Oropharyngeal, anal, rectal, and vulvar cancer increased 1.3% in women per year.
In men, oropharyngeal cancer incidence represented 81% of all HPV-related cancers—five times more than cases for women over 16 years.
HPV-related cancers in men increased 2.36% per year over 16 years, and oropharyngeal cancer had the biggest increase.
“Without standardized screening, HPV-related cancers—such as oropharyngeal cancers and anal rectal cancers—are increasing. 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,” Liao said in the news release.
Should PAP Tests Be Dropped as a Primary Screen for Cervical Cancer?
Today’s American Cancer Society (ACS) guidelines for cervical cancer screening denote the primary (FDA-designated) HPV test as the “preferred test” for people 25 to 65 years of age. A Pap test (or Pap smear) can be done at the same time, or in instances when a primary HPV test is not available, the ACS said.
HPV screening aims to detect high risk strains of HPV by looking for DNA in cervical cells and the Pap test involves collecting cells from the cervix for review in the medical laboratory for cancer and pre-cancer, the ACS added.
However, pathologists and cytotechnologists who have examined Pap smear slides for many years know that indications of cervical cancer are not always detected by HPV screening. A Pap test often picks up indications of cervical cancer that might not have been detected by the HPV test.
One reason is HPV tests only monitor about 20 of the genetic mutations known to cause cervical cancer. There are about 80 mutations that can cause cervical cancer, but most are so rare, it does not pay to include them in the HPV test panel.
“The Pap is not something that we should look at as replaceable. In some circumstances, we can get a Pap smear that has some significant cellular changes on it,” Jessica Shepherd, MD, an obstetrician and gynecologist at Baylor University Medical Center in Dallas, told USA Today.
Medicine Advancing, Pap Referrals Not So Much
In the 1990s, Pap tests were the front line for cervical cancer screening and a source of about 55 million referrals to clinical laboratories each year, recalls Robert Michel, Editor-in-Chief of Dark Daily and its sister publication The Dark Report.
“Interestingly, in the past decade, many cytotechnologists and laboratory scientists who started work in labs at the time of the new HPV screening guidelines and vaccination were unaware of the Pap test’s impact on revenue for clinical labs and pathology groups,” he said.
Medical advancements over the past 25 years have altered how providers screen women for cervical cancer and help them prevent it. And as HPV screening and HPV vaccination gained prominence, the standard Pap test became a kind of “co-pilot” to HPV testing. Unfortunately, this meant less oncology referrals to medical labs.
Findings may help physicians tailor cervical cancer therapies to specific gene mutations and improve the accuracy of diagnostic screening tests for this disease
New scientific knowledge about the role of human papillomavirus (HPV) in the growth of cervical cancer is creating excitement within the medical community. Among other things, these findings could encourage more widespread vaccination against HPV. That in turn would lead to reduced Pap smear testing by pathology laboratories over time.
For these reasons, cytopathologists and cytotechnologists will be particularly interested in the research findings that were published as a first-ever, international genomic study of cervical cancer, which was published online December 25, 2013, at Nature.com. Researchers discovered that the location where HPV integrates itself into the human genome, is where it causes amplified gene expression that promotes and elevates mutated gene activity that may cause cervical cancer to develop. (more…)
