CT Scans in a Single Year Could Result in 100,000 Future Cancers in the U.S.

 

• A risk model suggested that CT exams in 2023 were projected to lead to over 100,000 future cancers over the lifetime of exposed patients.
• Previous projections published in 2009 had estimated that approximately 29,000 future cancers would result from routine CT exposures.
• If utilization and radiation doses remain unchanged in future decades, CT could be responsible for approximately 5% of cancers diagnosed annually.

At current utilization and radiation dose levels, CT exams in 2023 were projected to lead to over 100,000 future cancers over the lifetime of exposed patients, according to an updated risk model.

Among an estimated 62 million patients who underwent 93 million CT examinations in 2023, approximately 103,000 radiation-induced cancers (90% uncertainty limits 96,400-109,500) were projected to result from these examinations, reported Rebecca Smith-Bindman, MD, of the University of California San Francisco, and colleagues in JAMA Internal Medicine.

Risks were higher in children and adolescents, but higher CT utilization in adults accounted for most (91%) radiation-induced cancers.

Previous projections published in 2009 had estimatedopens in a new tab or window that approximately 29,000 future cancers would result from routine CT exposures in the U.S.

"Despite public attention to the potential adverse effects, CT use has grown significantly since 2009," Smith-Bindman and team wrote. "If the number of new cancer diagnoses in the United States remains stable (1.95 million in 2023) and both the utilization and radiation doses from CT remain unchanged in future decades, CT could be responsible for approximately 5% of cancers diagnosed each year. This would place CT on par with other significant risk factors, such as alcohol consumption (5.4%) and excess body weight (7.6%)."

They noted that for the previous projections, the researchers used the best-available data on the volume and distribution of CT examinations, approximations of radiation doses, and associated absorbed organ doses. "Since then, the number of CT examinations performed annually in the United States has increased by more than 30%, more granular data have become available describing examination types, and more accurate methods have been developed for estimating organ dose," they pointed out.

In an accompanying Editor's Noteopens in a new tab or window, Ilana B. Richman, MD, MHS, of the Yale School of Medicine in New Haven, Connecticut, and Mitchell H. Katz, MD, of NYC Health + Hospitals in New York City, noted that while CT is "inextricably woven into the fabric of modern medicine," there are several ways to reduce the reliance on CT, including incorporating diagnostic algorithms at the point of care in order to reduce CT use among low-risk patients, offering alternative imaging solutions like MRI and ultrasound that don't use ionizing radiation, reducing radiation dose, and reducing variations in technique and dose across imaging centers.

"Lastly, educating clinicians about avoiding low-value testing and, in circumstances where alternatives are readily available, involving patients in the decision to do a CT scan may help shift culture and practice," they wrote.

The American College of Radiology (ACR) issued a statementopens in a new tab or window saying that the "theoretical radiation risk" reported in the study is consistent with prior modeling studies "that are not based on actual patient outcomes."

"There are no published studies directly linking CT scans (even multiple CT scans) to cancer," the ACR noted. "Americans should not forgo necessary, life-saving medical imaging and continue to discuss the benefits and risks of these exams with their healthcare providers."

For this study, Smith-Bindman and colleagues developed a risk model using a multicenter sample of CT examinations conducted between January 2018 and December 2020 from the University of California San Francisco International CT Dose Registry.

Lifetime radiation-induced cancer incidence was estimated by age, sex, and CT category using National Cancer Institute software based on the National Research Council's Biological Effects of Ionizing Radiation (BEIR) VII models and projected to the U.S. population using scaled examination counts.

Of the 61,510,000 patients who underwent 93 million CT examinations in 2023, 95.8% were adults, and 53% were female.

The most common cancers were lung cancer (22,400 cases), colon cancer (8,700 cases), leukemia (7,900 cases), and bladder cancer (7,100 cases) overall, while in female patients, breast cancer was second most common (5,700 cases).

Abdomen and pelvis CT exams were estimated to contribute the largest number of projected cancers (40%) in adults (37,500 cases), while head CT exams accounted for the largest number of cancers (53%) in children (5,100 cases).

Sensitivity analyses that reduced and increased organ doses by 20% reflected 22.2% fewer cancers to as many as 23.3% more cancers than the primary analysis.

Smith-Bindman and colleagues acknowledged that the study had several limitations, including the fact that the BEIR VII risk estimated model parameters were based on Japanese survivor outcomes "and questions remain about the transfer of radiation risks from the mid-20th century Japanese population to the current U.S. population."

Disclosures

This research was supported by awards from the National Cancer Institute, the Patient-Centered Outcomes Research Institute, and by residual class settlement funds in the matter of April Krueger v. Wyeth Inc.

Smith-Bindman is a cofounder of Alara Imaging, a company focused on improving the clinical and operational aspects of health systems, including collecting and reporting radiation dose and image quality associated with CT as part of payer-led quality programs.

A co-author reported receiving grants from the NIH.

Richman reported salary support from the Centers for Medicare & Medicaid Services to develop healthcare quality measures. Katz reported no disclosures.

Primary Source

JAMA Internal Medicine

Source Reference: opens in a new tab or windowSmith-Bindman R, et al "Projected lifetime cancer risks from current computed tomography imaging" JAMA Intern Med 2025; DOI: 10.1001/jamainternmed.2025.0505.

Secondary Source

JAMA Internal Medicine

Source Reference: opens in a new tab or windowRichman IB, Katz MH "Balancing computed tomography's benefits with radiation risks" JAMA Intern Med 2025; DOI: 10.1001/jamainternmed.2025.0514.

https://www.medpagetoday.com/hematologyoncology/othercancers/115112

'ACIP Backs Virus-Like Particle Chikungunya Vaccine for Travelers, Lab Workers'

 The CDC's Advisory Committee on Immunization Practices (ACIP) unanimously recommended that U.S. travelers ages 12 years and older receive the virus-like particle chikungunya vaccine (Vimkunya) when they travel to a country or territory with a chikungunya outbreak.

ACIP also unanimously backed a recommendation that this vaccine be considered in that same age group when traveling to or residing in a country or territory that isn't experiencing an outbreak but that poses an elevated risk for those planning to stay for at least 6 months.

In a separate unanimous vote, the committee recommended the vaccine for laboratory workers who potentially could be exposed to chikungunya virus. The panel agreed that vaccination isn't necessary for lab workers who handle routine clinical samples.

The virus-like particle chikungunya vaccine received accelerated approval from the FDA in February, and is one of two single-dose vaccines to prevent disease caused by the chikungunya virus. During a meeting last year, ACIP made recommendationsopens in a new tab or window on the use of the live-attenuated chikungunya vaccine (Ixchiq), which received accelerated approvalopens in a new tab or window in November 2023.

The chikungunya virus is widespread in tropical and subtropical regions. Infected mosquitoes spread the virus to people, triggering outbreaks that can be large and explosive. Fever and joint pain are the most common symptoms, but infection can also trigger muscle pain, headaches, rash, or joint swelling. There are no FDA-approved treatments for chikungunya infection. Although severe illness isn't common, infection can be fatal, primarily in infants and older adults.

During the meeting, ACIP also reviewed safety data from the Vaccine Adverse Event Reporting System (VAERS) that included six serious adverse events, including hospitalization, after vaccination with the live-attenuated vaccine. All six events occurred in people older than age 65 years who had multiple comorbidities, such as hypertension, hyperlipidemia, coronary artery disease, or diabetes.

These data and other post-licensing safety information prompted ACIP to revise age-related language in its earlier recommendations for the live-attenuated vaccine for those traveling to places without an active outbreak but with an elevated risk of one.

The updated ACIP recommendations are unchanged in their support for the live-attenuated vaccine in people ages 18 years and older who travel to a country or territory with a chikungunya outbreak. This vaccine may also be considered in that age group when a person travels to or resides in a country or territory that isn't experiencing an outbreak but that poses an elevated risk for people planning to stay for at least 6 months. ACIP's revision, however, targets older people in that extended-stay group.

ACIP voted unanimously to remove its earlier recommendation to consider the live-attenuated vaccine in people 65 years and older -- particularly those who have underlying medical conditions -- who will likely face at least moderate mosquito exposure in a country with no outbreak. ACIP's revised recommendations now note that being 65 years or older "is a precaution for use" of the live-attenuated vaccine in that situation.

All three votes were 14-0, with potential conflict-of-interest abstentions by ACIP member Lin Chen, MD, of Mount Auburn Hospital in Cambridge, Massachusetts.

The committee also reviewed proposed clinical guidance on chikungunya vaccine use in pregnant women and those who are breastfeeding. Although ACIP didn't vote on the measures, the draft guidance included the following recommendations:

• Pregnant women should defer vaccination until after delivery
• However, if a pregnant woman's chikungunya exposure risk is high, she should consider vaccination, given the risk of severe adverse outcomes in infants with infection
• In these cases, vaccination should happen at least 2 weeks before delivery, and it should be avoided during the first trimester
• Vaccination with the virus-like particle vaccine is preferred over the live-attenuated vaccine in pregnant women
• Immunization best-practice guidelines state that non-live vaccines such as the virus-like particle vaccine pose no risk for breastfeeding mothers or their infants

Steps to Sharpen Providers' Decision-Making Process

With two vaccine options available, some ACIP members wondered if there were enough data to make recommendations that help providers choose the best option for individual travelers. For example, if an older person were traveling to a place with no outbreak but an elevated chikungunya risk, should the virus-like particle vaccine be recommended over the live-attenuated vaccine?

Such moves may be premature, given the relative lack of strong safety data for the vaccines, explained Susan Hills, MBBS, the CDC lead on the ACIP chikungunya vaccines work group. Both vaccines were licensed through the accelerated approval process, and more definitive safety data should emerge from the vaccines' required postmarketing clinical trials and their real-world use during outbreaks.

In the case of older people traveling to higher-risk areas, "there is very clear evidence of the risk of chikungunya for this group," Hills said. "In some settings, such as if [the live-attenuated vaccine] is the only vaccine available, the benefit may fall on the side of using this vaccine -- although, with a precaution, it generally should be deferred."

Edwin Jose Asturias, MD, of the University of Colorado in Aurora and chair of the ACIP chikungunya vaccines work group, noted that "we believe that, at this point, we don't have enough data to lean toward preferential recommendation."

"There likely is going to be more evidence coming to us in the next few months, if not years, and I think this is an ongoing assessment," he said.

ACIP recommendations aren't considered final until they are published in the Morbidity and Mortality Weekly Report.

https://www.medpagetoday.com/meetingcoverage/acip/115162

'Get Granny on Gmail — computer and smartphone use lowers risk of brain decline by 42%'

 iPad? More like iPreserve. 

A new study found that older adults who regularly tap, scroll and surf their way through smartphones, computers and other digital devices are less likely to suffer from cognitive impairment.

The research casts doubt on the so-called “digital dementia hypothesis,” which suggests that too much screen time in our daily lives could speed up mental decline as we age.

3

The study findings may support the cogntive reserve theory.Koegelenberg/peopleimages.com – stock.adobe.com

The findings come at a time when American seniors are more plugged in than ever.

In a 2024 survey, the Pew Research Center found that a whopping 90% of US adults over the age of 65 are online. 

But it’s not just about browsing the web. AARP’s 2025 Tech Trends report shows that 91% of older adults own a smartphone, 78% have a smart TV and 62% use tablets.

For the meta-analysis, researchers sifted through 57 studies, involving more than 400,000 older adults from around the globe, to investigate the effects of tech on the brain.

The participants, averaging about 69 years old, had either taken cognitive tests or been diagnosed with mild cognitive impairment or dementia.

Researchers found that regular use of digital devices and the internet was associated with a 42% lower risk of cognitive impairment compared to those who used tech less frequently. 

“For the first generation that was exposed to digital tools, their use is associated with better cognitive functioning,” Dr. Jared Benge, a clinical neuropsychologist in UT Health Austin’s Comprehensive Memory Center, told the Guardian. 

“This is a more hopeful message than one might expect given concerns about brain rot, brain drain and digital dementia,” he continued. 

3

Surveys show approximately 90% of US adults 65 and older are online.Robert Peak – stock.adobe.com
But don’t ditch those screen time limits just yet.

“Our findings are not a blanket endorsement of mindless scrolling,” Benge told CNN. “They are instead a hint that the generation that gave us the internet has found ways to get some net positive benefits from these tools to the brain.”

This idea may support the “cognitive reserve theory,” which suggests that engaging with technology could actually provide cognitive benefits. 

However, more research is needed to fully understand the connection. For instance, scientists still aren’t sure if tech use itself helps prevent mental decline, or if people with better cognitive abilities are simply more inclined to use digital devices.

There were also a few gaps in the research. For one, the study doesn’t specify how much time older adults spend using their devices. 

Experts not involved with the analysis told CNN that this raises questions about whether there’s a harmful threshold when it comes to screen time. 

3

Research suggests roughly 1 in 10 US adults ages 65 and older have dementia.New Africa – stock.adobe.com
Additionally, the study doesn’t explore how seniors are actually using technology, which could impact how it affects their cognitive health.

“Using digital devices in the way that we use televisions — passive and sedentary, both physically and mentally — is not likely to be beneficial,” Dr. Michael Scullin, a cognitive neuroscientist at Baylor University in Texas, told The Guardian. 

“But, our computers and smartphones also can be mentally stimulating, afford social connections, and provide compensation for cognitive abilities that are declining with aging.”

The study also focuses on the first generation to engage with digital tools, but it doesn’t fully address how future generations — who have grown up with technology — will be affected.

“When you think about the kind of technology that this cohort would’ve been interacting with earlier in their lives, it’s a time when you had to really work to use technology,” Dr. Christopher Anderson, a neurologist who wasn’t involved in the study, told CNN. 

Their brains were also already well-formed, Benge added. 

Still, Anderson said the findings suggest a balanced approach to activities is the most beneficial.

“What this probably does more than anything else is provide some reassurance that there’s no association between at least moderate use of technology and cognitive decline,” he said. 

https://nypost.com/2025/04/17/health/study-digital-tech-use-lowers-risk-of-brain-decline-by-42/

BMO Capital Adjusts Price Target on Pfizer to $30 From $36

 Pfizer has an average rating of overweight and mean price target of $28.94, according to analysts polled by FactSet. 

https://www.marketscreener.com/quote/stock/PFIZER-INC-23365019/news/BMO-Capital-Adjusts-Price-Target-on-Pfizer-to-30-From-36-49650343/

Regeneron price target lowered to $547 from $575 at BofA

 BofA lowered the firm’s price target on Regeneron (REGN) to $547 from $575 and keeps an Underperform rating on the shares based on a lower multiple applied to the firm’s 2025 EPS forecast due to weaker earnings visibility and compression in the group average P/E multiple from tariffs and also drug pricing concerns. Ahead of the company’s Q1 report, the firm updated its U.S. Eylea estimates for the impact from the patient assistance funds closing, the analyst noted.

https://www.tipranks.com/news/the-fly/regeneron-price-target-lowered-to-547-from-575-at-bofa

BMO Capital Adjusts Merck Price Target to $89 From $96

 On Wednesday, BMO Capital Markets adjusted its outlook on Merck (NSE:PROR) & Co. Inc. (NYSE:MRK), reducing the pharmaceutical giant's price target from $105.00 to $96.00, while keeping a Market Perform rating on the stock. Analysts at BMO Capital cited a decrease in confidence stemming from recent shifts in expectations for Merck's vaccine, Gardasil, as a key reason for the price target adjustment.

The analysts noted that Merck's stock has been facing downward pressure, which is not solely attributable to fundamental reevaluations. The reduction in their estimates for Gardasil's performance significantly contributed to the new target price. The sentiment around Merck has been affected by what is perceived as a loss of confidence following a series of changing expectations regarding Gardasil, which has traditionally been a consistent product for the company. Despite recent market challenges,

BMO Capital's commentary highlighted the potential for Merck's management to navigate the company out of the current sentiment. However, this turnaround is contingent on the company's ability to consistently meet both long-term and short-term guidance. Additionally, the analysts believe that sentiment-shifting events, such as the approval of celsrovimab, fast uptake, and additional data on GLP-1 treatments, could contribute positively to Merck's outlook. With a market capitalization of $223.67 billion and consistent revenue growth, Merck remains a prominent player in the pharmaceuticals industry.

https://www.investing.com/news/analyst-ratings/bmo-capital-cuts-merck-stock-target-to-96-retains-rating-93CH-3851292

BMO Capital Adjusts Biogen Price Target to $128 From $139

  Biogen has an average rating of overweight and mean price target of $191.11, according to analysts polled by FactSet.

https://www.marketscreener.com/quote/stock/BIOGEN-INC-4853/news/BMO-Capital-Adjusts-Biogen-Price-Target-to-128-From-139-49650341/