Norwegian researchers reviewed large clinical trials of six common cancer screenings, including clinical laboratory tests, but some experts question the findings
Cancer screenings are a critical tool for diagnosis and treatment. But how much do they actually extend the lives of patients? According to researchers at the University of Oslo in Norway, not by much. They recently conducted a review and meta-analysis of 18 long-term clinical trials, five of the six most commonly used types of cancer screening—including two clinical laboratory tests—and found that with few exceptions, the screenings did not significantly extend lifespans.
The 18 long-term clinical trials included in the study were randomized trials that collectively included a total of 2.1 million participants. Median follow-up periods of 10 to 15 years were used to gauge estimated lifetime gain and mortality.
“The findings of this meta-analysis suggest that current evidence does not substantiate the claim that common cancer screening tests save lives by extending lifetime, except possibly for colorectal cancer screening with sigmoidoscopy,” the researchers wrote in their published paper.
The researchers noted, however, that their analysis does not suggest all screenings should be abandoned. They also acknowledged that some lives are saved by screenings.
“Without screening, these patients may have died of cancer because it would have been detected at a later, incurable stage,” the scientists wrote, MedPage Today reported. “Thus, these patients experience a gain in lifetime.”
Still, some independent experts questioned the validity of the findings.
Gastroenterologist Michael Bretthauer, MD, PhD (above), a professor at the University of Oslo in Norway led the research into cancer screenings. In their JAMA Internal Medicine paper, he and his team wrote, “The findings of this meta-analysis suggest that colorectal cancer screening with sigmoidoscopy may extend life by approximately three months; lifetime gain for other screening tests appears to be unlikely or uncertain.” How their findings might affect clinical laboratory and anatomic pathology screening for cancer remains to be seen. (Photo copyright: University of Oslo.)
Pros and Cons of Cancer Screening
The clinical trials, according to MedPage Today and Oncology Nursing News covered the following tests:
Mammography screening for breast cancer (two trials).
As reported in these trials, “colorectal cancer screening with sigmoidoscopy prolonged lifetime by 110 days, while fecal testing and mammography screening did not prolong life,” the researchers wrote. “An extension of 37 days was noted for prostate cancer screening with prostate-specific antigen testing and 107 days with lung cancer screening using computed tomography, but estimates are uncertain.”
The American Cancer Society (ACS) recommends certain types of screening tests to detect cancers and pre-cancers before they can spread, thus improving the chances for survival.
The ACS advises screenings for breast cancer, colorectal cancer, and cervical cancer regardless of whether the individual is considered high risk. Lung cancer screenings are advised for people with a history of smoking. Men who are 45 to 50 or older should discuss the pros and cons of prostate cancer screening with their healthcare providers, the ACS states.
A CNN report about the University of Oslo study noted that the benefits and drawbacks of cancer screening have long been well known to doctors.
“Some positive screening results are false positives, which can lead to unnecessary anxiety as well as additional screening that can be expensive,” CNN reported. “Tests can also give a false negative and thus a false sense of security. Sometimes too, treatment can be unnecessary, resulting in a net harm rather than a net benefit, studies show.”
In their JAMA paper, the University of Oslo researchers wrote, “The critical question is whether the benefits for the few are sufficiently large to warrant the associated harms for many. It is entirely possible that multicancer detection blood tests do save lives and warrant the attendant costs and harms. But we will never know unless we ask,” CNN reported.
Hidden Impact on Cancer Mortality
ACS Chief Scientific Officer William Dahut, MD, told CNN that screenings may have an impact on cancer mortality in ways that might not be apparent from randomized trials. He noted that there’s been a decline in deaths from cervical cancer and prostate cancer since doctors began advising routine testing.
“Cancer screening was never really designed to increase longevity,” Dahut said. “Screenings are really designed to decrease premature deaths from cancer.” For example, “if a person’s life expectancy at birth was 80, a cancer screening may prevent their premature death at 65, but it wouldn’t necessarily mean they’d live to be 90 instead of the predicted 80,” CNN reported.
Dahut told CNN that fully assessing the impact of cancer screenings on life expectancy would require a clinical trial larger than those in the new study, and one that followed patients “for a very long time.”
“From its title, one would have expected this paper to be based on analysis of individual lifetime data. However, it is not,” he wrote in a compilation of expert commentary from the UK’s Science Media Center. “The paper’s conclusions are based on arithmetic manipulation of relative rates of all-cause mortality in some of the screening trials. It is therefore difficult to give credence to the claim that screening largely does not extend expected lifetime.”
He also questioned the inclusion of one particular trial in the University of Oslo study—the Canadian National Breast Screening Study—“as there is now public domain evidence of subversion of the randomization in this trial,” he added.
Another expert, Leigh Jackson, PhD, of the University of Exeter in the UK, described the University of Oslo study as “methodologically sound with some limitations which the authors clearly state.”
But he observed that “the focus on 2.1 million individuals is slightly misleading. The study considered many different screening tests and 2.1 million was indeed the total number of included patients, however, no calculation included that many people.”
Jackson also characterized the length of follow-up as a limitation. “This may have limited the amount of data included and also not considering longer follow-up may tend to underestimate the effects of screening,” he said.
This published study—along with the range of credible criticisms offered by other scientists—demonstrates how analysis of huge volumes of data is making it possible to tease out useful new insights. Clinical laboratory managers and pathologists can expect to see other examples of researchers assembling large quantities of data across different areas of medicine. This huge pools of data will be analyzed to determine the effectiveness of many medical procedures that have been performed for years with a belief that they are helpful.
GI pathologists will be interested in how the Endoculus device uses tank-like treads to traverse the gastrointestinal tract, where it can capture images and perform biopsies
Gastroenterologists (GI) may soon gain a useful new tool for use in gathering both biopsies and diagnostic information when examining the gastrointestinal tract. Ongoing development of a new robotic device promises both capabilities using technology that will be of interest to GI pathologists and clinical laboratory scientists.
The minute robotic device uses tank-like treads to traverse the colon. While there, it can capture live images and perform biopsies under the control of a gastroenterologist. The researchers believe the robotic technology will benefit GIs performing the colonoscopies as well as the pathologists called upon to analyze biopsies.
“Currently, endoscopy consists of a gastroenterologist using a semi-rigid, long rope-like device and endoscope to propel through your colon manually,” Gregory Formosa, PhD (above) a member of the AMTL team that developed Endoculus, said in a YouTube video describing the device. “We think that a robotic capsule endoscope can replace conventional endoscopes by making them faster, safer, and more robust than a human operator can do currently with traditional techniques,” he added. (Photo copyright: University of Colorado.)
AMTL researcher Gregory Formosa, PhD, said the team’s goal is to “have a capsule-sized robot that can actively traverse [a patient’s] entire gastrointestinal tract and send out diagnostics in real time, as well as autonomously navigate itself to localize problematic areas within [the] intestinal tract.”
Formosa noted that colorectal cancer is “the third-most fatal and diagnosed cancer in the United States.” But if caught at an early stage, these cancers are “95% treatable,” he added. “So, if we can get people screened early, we definitely can reduce the fatality rate of colorectal cancers significantly.”
Currently about the size of a C battery, Endoculus (above) is a “fully packed medical device, complete with a camera, an air pump for inflating the colon, a water pump for cleaning, and a tool port for holding biopsy snares,” states a University of Colorado news story, titled, “A Robot May One Day Perform Your Colonoscopy.” (Photo copyright: University of Colorado.)
How Endoculus Works
One key to the device are the four treads, which are designed for traction on digestive tissue.
“You have to forget about everything you know from a locomotion standpoint because driving around inside the body is very different than driving around in a car,” said Rentschler in the University of Colorado news story. “The environment is highly deformable. It’s very slick. There are sharp peaks that you have to go over.”
The university news story noted the current availability of ingestible “pill cams” that can take photos as they travel through the digestive system. But once swallowed, their movements cannot be controlled.
“For our robots to be able to reach those regions that [can be] reached with a pill-cam—but also be able to stop and look around—that could be a big paradigm shift in the way we view these procedures,” said Micah Prendergast, PhD, an AMTL research team member.
Could Biopsies Be Diagnosed In Situ with Endoculus?
The researchers currently view Endoculus as a potentially better way to perform conventional biopsies. But could it lead to bigger advancements?
“Researchers continue to develop devices to help various specialist physicians—in this case GIs—do more when treating patients,” said Dark Daily Publisher and Editor-in-Chief Robert Michel. “This device fits that description. It is designed to improve the ability of GIs to evaluate the colon. Not only does this device do that, but it can also collect a biopsy at sites of interest. In this way, it is a device that can be a benefit to pathologists who will analyze the biopsy.
“With improvements in digital cameras and associated AI-powered analytical tools, the day might not be far off when a device like this can use the camera and artificial intelligence to diagnose the tissue of interest in situ,” he added. “This might create the opportunity for pathologists to be present in the exam room during the procedure, or even viewing the images remotely.
“Not only would that eliminate the need to collect a tissue specimen that must then be sent to a pathology lab, but it would create a new opportunity for pathologists to add value to patient care while shortening the time to diagnosis for the tissue of interest during these procedures,” Michel noted.
Doctors may begin ordering FITs in greater numbers, increasing the demand on clinical laboratories to process these home tests
All clinical laboratory managers and pathologists know that timely screening for colon cancer is an effective way to detect cancer early, when it is easiest to treat. But, invasive diagnostic approaches such as colonoscopies are not popular with consumers. Now comes news of a large-scale study that indicates the non-invasive fecal immunochemical test (FIT) can be as effective as a colonoscopy when screening for colon cancer.
FITs performed annually may be as effective as colonoscopies at detecting colorectal cancer (CRC) for those at average risk of developing the disease. That’s the conclusion of a study conducted at the Regenstrief Institute, a private, non-profit research organization affiliated with the Indiana University School of Medicine in Indianapolis, Ind.
The researchers published their findings in the Annals of Internal Medicine (AIM), a journal published by the American College of Physicians (ACP). The team reviewed data from 31 previous studies. They then analyzed the test results from more than 120,000 average-risk patients who took a FIT and then had a colonoscopy. After comparing the results between the two tests, the researchers concluded that the FIT is a sufficient screening tool for colon cancer.
FIT is Easy, Safe, and Inexpensive
As a medical laboratory test, the FIT is low risk, non-invasive,
and inexpensive. In addition, the FIT can detect most cancers in the first
application, according to the Regenstrief Institute researchers. They recommend
that the FIT be performed on an annual basis for people at average risk for
getting colorectal cancers.
“This non-invasive test for colon cancer screening is available for average risk people,” Imperiale told NBC News. “They should discuss with their providers whether it is appropriate for them.”
FIT is performed in the privacy of the patient’s home. To
use the test, an individual collects a bowel specimen in a receptacle provided
in a FIT kit. They then send the specimen to a clinical laboratory for
evaluation. The FIT requires no special preparations and medicines and food do
not interfere with the test results.
Thomas Imperiale, MD (above), is a Lawrence Lumeng Professor of Gastroenterology and Hepatology at Indiana University School of Medicine, and a research scientist at the Regenstrief Institute. He led a study which concluded that FITs are as effective as colonoscopies at detecting cancer in average risk patient populations. Should these conclusions become widely accepted, doctors may begin ordering FITs in greater numbers, increasing the demand on clinical laboratories that process the tests. (Photo copyright: Indiana University School of Medicine.)
‘A Preventative Health Success Story’
The FIT can be calibrated to different sensitivities at the
lab when determining results. Imperiale and his team found that 95% of cancers
were detected when the FIT was set to a higher sensitivity, however, that
setting resulted in 10% false positives. At lower sensitivity the FIT produced
fewer false positives (5%), but also caught fewer cancers (75%). However, when
the FIT was performed every year, the cancer detection rate was similar at both
sensitivities over a two-year period.
“FIT is an excellent option for colon cancer screening only if it is performed consistently on a yearly basis,” Felice Schnoll-Sussman, MD, told NBC News. Sussman is a gastroenterologist and Professor of Clinical Medicine at Weill Cornell Medicine. “Colon cancer screening and its impact on decreasing rates of colon cancer is a preventative health success story, although we have a way to go to increase rates to our previous desired goal of 80% screened in the US by 2018.”
The FIT looks for hidden blood in the stool by detecting protein hemoglobin found in red blood cells. A normal result indicates that FIT did not detect any blood in the stool and the test should be repeated annually. If the FIT comes back positive for blood in the stool, other tests, such as a sigmoidoscopy or colonoscopy should be performed. Cancers in the colon may not always bleed and the FIT only detects blood from the lower intestines.
Patients are Skipping the Colonoscopy
Approximately 35% of individuals who should be receiving colonoscopies do not undergo the test, NBC News noted. The American Cancer Society (ACS) lists the top five reasons people don’t get screened for colorectal cancer are that they:
fear the test will be difficult or painful;
have no family history of the disease and feel
testing is unnecessary;
have no symptoms and think screening is only for
those with symptoms;
are concerned about the costs associated with
screening; and
they are concerned about the complexities of
taking the tests, including taking time off from work, transportation after the
procedure, and high out-of-pocket expenses.
“Colorectal cancer screening is one of the best opportunities to prevent cancer or diagnose it early, when it’s most treatable,” Richard Wender, MD, Chief Cancer Control Officer for the ACS stated in a press release. “Despite this compelling reason to be screened, many people either have never had a colorectal cancer screening test or are not up to date with screening.”
Colorectal cancer is the third most common cancer diagnosed in both men and women in the United States. The ACS estimates there will be 101,420 new cases of colon cancer and 44,180 new cases of rectal cancer diagnosed this year. The disease is expected to be responsible for approximately 51,020 deaths in 2019.
New cases of the disease have been steadily decreasing over
the past few decades in most age populations, primarily due to early screening.
However, the overall death rate among people younger than age 55 has increased
1% per year between 2007 and 2016. The ACS estimates there are now more than
one million colorectal cancer survivors living in the US.
The ACS recommends that average-risk individuals start
regular colorectal cancer screenings at age 45. The five-year survival rate for
colon cancer patients is 90% when there is no sign that the cancer has spread
outside the colon.
Clinical laboratory professionals may find it unpleasant to
test FIT specimens. Opening the specimen containers and extracting the samples
can be messy and malodorous. However, FITs are essential, critical tests that
can save many lives.
The self-monitoring/self-test market is expected to swell to $19 billion by 2019, offering opportunities for pathologists and clinical laboratories to advise patients and ensure the proper use of home tests
Might the future of clinical laboratory tests be sitting on the shelf at your corner pharmacy right now? Patient self-testing and screening kits continue to garner the approvals of Consumer Reports’ medical advisors.
That’s happening because the Food and Drug Administration (FDA) continues to clear many do-it-yourself tests that traditionally were performed in medical laboratories by qualified personnel, much to the chagrin of some doctors.
Empowered healthcare consumers are checking their cholesterol, monitoring their diabetes, and more, using health screening kits that range from $8 to $175, according to a Consumer Reports on Health article, which advised consumers to use self-tests judiciously and share the results with their physicians. (more…)
Researchers find shopping for medical laboratory tests increased by nearly 50%, and people are saving more than a million dollars annually by shopping for blood tests
Each year, more consumers use online healthcare price-shopping tools to find hospitals, physicians, and clinical laboratories that have the lowest prices. And medical laboratory tests is among the top services on their lists!
Researchers at Vitals of Lyndhurst, NJ, a company that publishes online physician ratings, analyzed how consumers were using its price and quality transparency tools. They confirmed that shopping for medical laboratory tests/blood work is one of the top healthcare procedures checked by consumers.
According to a recent Vitals press release, approximately 46% more people shopped for blood tests in 2015 than the year before, and they saved $1,149,682 by doing so. That’s because their health plans reward them for selecting good quality and low-price providers, as well as adopting healthy behaviors, such as losing weight, exercising more, and lowering high cholesterol scores. (more…)
