A new screening test could help diagnose lung cancer earlier than traditional CT scans.
- About 1.8 million deaths each year are
attributable to lung cancer, making it the leading cause of cancer death
around the world.
- Only 16% of people with lung cancer
receive an early diagnosis, which offers a much higher survival rate.
- Researchers say they have developed a new way to detect lung cancer at its earliest stages using an inhaler and a simple urine test.
About 1.8 million deaths each year are
attributable to lung cancer, making it the leading cause of
cancer death globally.
Previous research reports that only 16% of people receive a lung
cancer diagnosis at an early stage.
However, as with any type of cancer, an early diagnosis of
lung cancer offers better outcomes. Studies show that the average 5-year lung cancer survival rate in
the U.S. is as low as 18%, but that rate jumps as high as 55% when caught at an
early stage.
Now, researchers from the Massachusetts Institute of
Technology (MIT) say they have developed a new way to detect lung cancer at its
earliest stages using an inhaler and a simple urine test.
The study was recently published in the
journal Science Advances.
Why is lung cancer hard to detect early?
Current guidelines recommend anyone between the ages
of 55 and 80 years old who has a history of heavy smoking should be screened for lung cancer.
Right now, the gold standard for lung cancer screening
is the low-dose computed tomography (CT) scan. However, CT
scans can sometimes produce false positives or negatives.
Past research shows that the majority of lung cancer cases are
diagnosed at an advanced stage because most people do not have any symptoms in
the earliest stages.
“Lung cancer is such a difficult diagnosis for many
patients because it doesn’t give us many warning signs before it’s at an
advanced stage,” explained Dr. Michael Spallone,
a thoracic surgeon with Hackensack University Medical Center in New Jersey who
was not involved in this study. “In fact, many of the lung cancers we diagnose
on a day-to-day basis is based off of incidental findings; in other words, the
patient has had imaging done for another reason, i.e. chest pain or cough, that
just so happened to pick up an unrelated finding of a lung nodule or mass.”
“Many lung cancers can be cured if detected early,
particularly with surgical resection,” Spallone told Medical News Today. “However,
surgery is an available option only before the cancer has spread or become too
invasive to resect. Therefore, anything that gives us an earlier warning that
something may be going on, is an advantage to us and patients alike.”
Lung cancer screening in 20 minutes
For this study, researchers used a new technology
using nanoparticle sensors
that are breathed in through the use of an inhaler or nebulizer.
The nanoparticle sensors are coated with a reporter,
such as a DNA barcode, making them into “nano-detectives” for lung cancer
screening, said Qian Zhong, a
research scientist at MIT and co-lead author of this study.
“Upon inhalation, these DNA-barcoded nanoparticles
patrol the lungs in search of cancer-associated protease signatures,” Zhong told Medical News Today.
“The nanoparticles are engineered to be activated by disease signals in the
tumor microenvironment, releasing the DNA barcodes into the bloodstream, which
are then filtered into the urine.”
“We analyze these urinary ‘fingerprints’ using a
multiplexed quantitative lateral flow assay,” he added. “Results can be
obtained at room temperature from the paper test within 20 minutes.”
Could new lung cancer inhaler test replace CT
scans?
As access to CT scans is limited in certain parts of
the world, scientists believe this inhaler screening test may provide another
option.
“CT remains one of the best imaging modalities with
high resolution to visualize malignant nodules when substantial respiratory symptoms
associated with lung cancer have been spotted or developed,” Dr. Edward Tan, a
former postdoctoral research fellow at MIT and co-lead author of this study,
explained to Medical News Today. “However, up to 95 percent of CT-positive patients
are false positive. For those early nodules that cannot be confirmed benign or
malignant in a single visit or are located in deep lung areas, one or more CT
scans in (the) following months or years are needed for confirmation.
Unfortunately, many patients in reality don’t follow the recommendations or
miss the follow-up appointments.”
“The whole process is costly and always completed in
several visits, which is definitely [a burden] to low-income households which
live pay check by pay check,” Tan added. “Therefore, many at-risk people from
low-income households have limited/no access to this lung cancer program even
in the U.S., not to mention in other low-income countries. So we believe that
the accessibility to this kind of screening could have a big impact in those
contexts.”
Future lung cancer research steps
This new lung cancer screening test was tested on a
mouse model during this study. The mice were genetically engineered to develop
lung tumors similar to those seen in humans.
Through various experiments, scientists measured the
levels of 20 different sensors, ultimately identifying four required sensors
for diagnostic results. These four sensors were tested again in the mouse model
and researchers reported it could accurately detect early-stage lung cancer
tumors.
The research team reportedly plans to next test the
sensors on human biopsy samples and eventually perform clinical trials on
humans.
“We are actively exploring the platform’s utility for
detecting other pulmonary diseases, such as infections,” Tan said. “Another
exciting application of the PATROL platform is therapeutic monitoring. For
instance, it could serve as a tool to assess patients’ responses to specific
treatments. Regarding translation to clinical use, further optimization of the
nanosensor probes and extensive preclinical studies are required.”
‘Exciting’
technology and innovation in lung cancer diagnosis
After reviewing this study, Spallone told MNT that this
type of technology and innovation is so exciting to see.
“It’s part of the reason that many of us choose to go
into medicine in the first place,” he said. “Medicine is constantly changing,
adapting, and improving. In the cancer world, particularly lung cancer, the
name of the game is early detection. Anything that gets us an earlier diagnosis
has the potential to improve outcomes for patients.”
“The other aspect that I love is the ease of the
proposed test,” Spallone added. “Many patients are familiar with using an
inhaler and a urine test is one of simplest diagnostic tools available for
patients. It doesn’t involve needles or radiation such as an X-ray or CT scan. Any time you can simplify testing
and make it safe, patients tend to be more comfortable taking advantage of it.”
Spallone commented that the obvious next step for this
type of research is to test its effectiveness in humans.
“The article highlights the fact that human lung
cancer is more complicated than the mouse models it was initially tested on,”
he explained. “You want to make sure the test is sensitive — it knows when
cancer is there — and you want it to be specific — it knows that it’s cancer
and not something else. This often takes time and meticulous effort on the part
of the research team. That being said, I have a lot of optimism that it could
become a more attractive and available option to those appropriate for lung
cancer screening in (the) future.”
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