Low-dose CT Scan effective for diagnosing colonic diverticulitis

Low-dose CT effective for diagnosing colonic diverticulitis

By AuntMinnie.com staff writers

April 9, 2021 — A low-dose protocol of intravenous contrast-enhanced 2-mSv CT is comparable to conventional-dose CT for diagnosing right colonic diverticulitis, according to a study published April 8 in the American Journal of Roentgenology.

The results could help clinicians better distinguish right colonic diverticulitis from appendicitis, according to a team led by Dr. Hae Young Kim, PhD, of Seoul National University Bundang Hospital in South Korea.

“By mitigating concern of missed diagnosis of right colonic diverticulitis, our results further support the use of low-dose CT for suspected appendicitis,” the group wrote.

Kim and colleagues performed a study that included 3,074 patients between the ages of 15 and 44 seen at 20 hospitals. The patients were randomized into two groups, one that underwent contrast-enhanced 2-mSv CT (1,535) and another that underwent conventional CT (1,539) between December 2013 and August 2016. A team of 161 radiologists read the exams, recommending alternative diagnoses in 976 of the low-dose CT exams and in 924 of the conventional CT exams.

Intravenous contrast-enhanced 2-mSv 4-mm-thick transverse and coronal CT images show inflamed diverticula, segmental colonic wall thickening, and adjacent pericolic fat stranding

Intravenous contrast-enhanced 2-mSv 4-mm-thick transverse and coronal (B) CT images show inflamed diverticula (arrows), segmental colonic wall thickening, and adjacent pericolic fat stranding. Image and caption courtesy of the American Roentgen Ray Society and the American Journal of Roentgenology.

The researchers found that true positives, true negatives, sensitivity, and specificity results between the two groups were not statistically significant, demonstrating the efficacy of low-dose CT for this indication, they concluded.

National nonprofits launch cancer screening campaign in COVID-19 era

National nonprofits launch cancer screening campaign in COVID-19 era

By AuntMinnie.com staff writers

April 8, 2021 — The Community Oncology Alliance and CancerCare, two national nonprofit advocacy groups in oncology, announced the launch of a campaign called “Time to Screen” that’s intended to counter delays reported in preventive care due to COVID-19.

The campaign will allow patients to schedule appointments and learn about the importance of early cancer detection, according to the organizations. It will also provide educational resources, including a toll-free hotline and website featuring information on screenings for breast, colorectal, cervical, prostate, lung, and skin cancer.

The initiative is prompted in part by a study published July 27, 2020, in JCO Clinical Cancer Informatics that showed the number of screening exams for colorectal and breast cancer performed at 20 U.S. hospitals dropped by nearly 90% in April due to the COVID-19 pandemic.

Community Oncology Alliance and CancerCare urge anyone needing to schedule a cancer screening, or wondering if they should be screened, to visit TimeToScreen.org.

Chest CT assesses COPD mortality risk

Chest CT assesses COPD mortality risk

By Kate Madden Yee, AuntMinnie.com staff writer

April 6, 2021 — Routine chest CT scans offer body composition information that could help clinicians better evaluate the mortality risk of patients with chronic obstructive pulmonary disease (COPD), according to a study published April 6 in Radiology.

This additional data could translate to mitigated risk due to earlier intervention, a team led by Dr. Farhad Pishgar of Johns Hopkins University School of Medicine in Baltimore said in a statement released by the journal.

“In theory, CT-derived body composition assessments would provide an opportunity for earlier interventions in patients who face a higher risk of adverse health events,” the group said.

Chest CT has long been used to assess lung health in people with COPD, but the exam could also offer a way to evaluate obesity and sarcopenia through soft-tissue biomarkers. Pishgar’s group used chest CT data to investigate links between imaging-based soft-tissue markers and all-cause mortality in patients with COPD.

The study included information from 2,994 patients enrolled in the Multi-Ethnic Study of Atherosclerosis (MESA) who underwent routine chest CT between 2010 and 2012; of these, 265 people had COPD. The group extracted mortality data from the National Death Index, finding that 49 (18%) of the COPD patients died of the condition over the follow-up period.

The team found that fat levels of the COPD patients affected mortality rates, but this effect depended on what type of fat: Those with greater intermuscular fat had higher all-cause mortality rates, while higher levels of subcutaneous fat tissue were associated with lower risk of all-cause mortality.

Association of imaging-derived markers with all-cause mortality among patients with COPD 
Characteristic Unadjusted hazard ratio Adjusted hazard ratio*
Subcutaneous adipose tissue index 0.58 0.22
Intermuscular adipose tissue index 1.26 1.39

*Adjusted for age, sex, race/ethnicity, body mass index, baseline pulse oximetry, smoking status, pack-years of cigarette smoking, and employment status.

Axial chest CT examination in a 54-year-old participant

Axial chest CT examination in a 54-year-old participant. (A) On the axial noncontrast chest CT image, the pectoralis muscle (PM) area was segmented and measured in the section above the aortic arch. (B) The subcutaneous adipose tissue (SAT) area as the area between the pectoralis muscle and the skin surface on the same section was also measured and the attenuation of pixels in the subcutaneous adipose tissue area was used to determine the individualized threshold for the intermuscular adipose tissue. (C) The intermuscular adipose tissue within the pectoralis muscle was segmented as the areas with Hounsfield units below this threshold for the intermuscular adipose tissue (IMAT) (arrowheads). Images and caption courtesy of the RSNA.

“Compared with subcutaneous adipose tissue quantification, intermuscular adipose tissue may be a better marker for predicting all-cause mortality in patients with COPD … [in part because] the intermuscular adipose tissue index is an indicator of other underlying comorbidities (e.g., diabetes and hypertension) and may predict the all-cause mortality better,” the authors wrote.

The study suggests that soft-tissue markers identified on chest CT offer a reliable way to estimate mortality risk in COPD patients, wrote Dr. Nicola Sverzellati, PhD, and colleague Dr. Filippo Cademartiri, PhD, both of the University of Parma in Italy, in an accompanying commentary.

“Chest CT has the potential to become a powerful tool in the quest for personalized medicine in COPD,” Sverzellati and Cademartiri wrote. “Whether it is incorporated into routine assessment for patients with COPD will ultimately depend on our ability to demonstrate that this information changes treatment and improves outcomes.”

CT finds increased rates of emphysema in lungs of marijuana smokers

CT finds increased rates of emphysema in lungs of marijuana smokers

By AuntMinnie.com staff writers

April 2, 2021 — Chest CT shows increased rates of emphysema in marijuana smokers compared with nonsmokers and tobacco smokers, according to research to be presented at the upcoming virtual American Roentgen Ray Society (ARRS) meeting.

The researchers led by Dr. Luke Murtha of Ottawa Hospital in Canada also found that marijuana smokers have greater rates of paraseptal emphysema.

“Marijuana smoking is also associated with airways disease, including bronchial wall thickening, bronchiectasis, and bronchiolar mucoid impaction, in comparison to both the control group and tobacco-only group,” Murtha said in a statement released by the ARRS.

The investigators gathered data from Ottawa Hospital’s PACS to create three groups of patients matched for age and sex: marijuana smokers (56), nonsmokers/nonmarijuana users (57), and tobacco-only smokers (33). Two radiologists blinded to smoking history read each patient’s chest CT.

Murtha’s group found the following:

  • The rate of emphysema among marijuana-smoking patients was 75%, compared with 5% of the nonsmoking group.
  • The increase of emphysema was 93% among marijuana smokers, compared with 66% of tobacco smokers.
  • The proportion of paraseptal emphysema was 53% among marijuana smokers, compared with 24% among tobacco-only smokers and 7% among nonsmokers.

“Given that marijuana use is increasing, particularly within nations such as Canada, that have legalized the substance, it is important for us, as radiologists, to define specific findings associated with its consumption,” Murtha’s team concluded.

How can access to CT lung cancer screening be improved?

How can access to CT lung cancer screening be improved?

By Kate Madden Yee, AuntMinnie.com staff writer

April 1, 2021 — Researchers are sounding the alarm yet again that access and adherence to CT lung cancer screening must be improved, according to two studies published March 30 in the Annals of the American Thoracic Society and the Journal of the American College of Radiology.

Since lung cancer is a leading cause of cancer death in the U.S., access to and compliance with screening is crucial, wrote a team led by Soumya Niranjan, PhD, of the University of Alabama at Birmingham. But geographic factors may prevent some patients from getting the screening they need.

“The U.S. Preventive Services Task Force (USPSTF) has recommended annual screening with low-dose CT for high-risk patients since 2013, though in 2015 less than 4% of those eligible were screened,” the group wrote.

Uptake of CT lung cancer screening has been much discussed lately, especially since on March 9 the USPSTF issued updated guidelines that lowered the age of people who are eligible to be screened and reduced the threshold in their smoking history to make them eligible. Yet the question of whether patients have adequate access to screening remains.

In a study in Annals of the American Thoracic Society, Niranjan and colleagues sought to assess the geographic availability of CT screening by evaluating travel time to lung cancer screening centers for patients from underserved areas.

The researchers examined any association between travel time and lung cancer mortality. Data included in the study came from drive-time analyses to designated screening centers of excellence in the 48 contiguous U.S states in 2017. They found that 36% of counties with high lung cancer mortality rates required patients to drive more than an hour to a center for screening; these counties were predominately in the South and Appalachian regions of the country. They also found an inverse association between distance to a screening center and lung cancer mortality.

“Expanding screening centers to underserved areas could play an important role in increasing screening rates and ultimately reducing lung cancer mortality in the U.S.,” the group concluded.

In a related study published in the Journal of the American College of Radiology, a team led by Erin Hirsch of the University of Colorado Anschutz Medical Campus in Aurora used data from a Colorado claims dataset to evaluate associations between CT lung cancer screening adherence and demographic, comorbidity, and geographic factors.

The team found the following factors to be associated with lower adherence to lung cancer screening:

  • Being between 75 and 79 (hazard ratio [HR], 0.79)
  • Living in a rural area (HR, 0.56)
  • Belong to Medicare fee-for-service (HR, 0.45) or Medicaid (HR, 0.5)

“[Our study] provides insight into populations that might benefit from specific interventions targeted toward improving adherence and maximizing lung cancer screening benefit,” the group concluded. “Quantifying population-based adherence rates and understanding factors associated with annual adherence are critical to improving screening adherence and reducing lung cancer death.”

ASTRO survey finds rise in advanced-stage cancer

ASTRO survey finds rise in advanced-stage cancer

By Erik L. Ridley, AuntMinnie.com staff writer

March 30, 2021 — The disruption of cancer screening programs during the COVID-19 pandemic has had a very real impact. In a recent survey by the American Society for Radiation Oncology (ASTRO), 66% of radiation therapy practice leaders said that new patients are presenting with more advanced-stage cancers.

In addition, 73% indicated that physicians in their practices are noticing that patients are not receiving cancer screenings, and 66% said that existing patients have experienced an interruption in their radiation therapy due to the pandemic.

These results show the consequences of pandemic-driven drops in cancer screening and diagnostics, especially for underserved populations, according to ASTRO Chair Dr. Thomas Eichler.

“Because the pandemic and cancer cause disproportionately more harm for Black and other medically underserved populations, these rates may be even higher for some vulnerable communities,” Eichler said in a statement from ASTRO.

ASTRO emailed the online survey to 509 radiation oncologists identified in its member database as medical directors of U.S.-based radiation oncology practices. Of these, 117 (23%) completed the survey online between January 15 and February 7.

In other survey results, ASTRO said that the following enhanced safety protocols remain widespread at radiation therapy clinics:

  • Social distancing in the clinic: 100%
  • Masking for patients and staff: 99%
  • Screening patients and staff for COVID-19 exposure: 95%
  • Increased sterilization: 93%
  • Face shields for staff during procedures: 80%
  • No-visitor policies: 73%

Clinics have largely stopped deferring or postponing radiation therapy treatments, according to ASTRO. Only 15% reported postponing treatment in January and February, compared with 92% in April 2020, according to the societies. Furthermore, 12% indicated that they were deferring any new patients in 2021, compared with 75% in the early weeks of the pandemic, ASTRO said.

In troublesome results, 40% of practices surveyed still reported difficulty accessing personal protective equipment (PPE), medical-grade hand sanitizer, or other critical supplies in the initial months of 2021, ASTRO said. Alarmingly, 59% of physicians said that vaccination efforts at their practice were limited by hesitation to receive the vaccine among staff, while 52% also noted hesitancy among patients. In addition, 53% of physicians said that these efforts were limited by access to the vaccine.

The survey also revealed that the pandemic isn’t affecting clinics equally, the society said. Radiation oncologists at community-based private practices were more likely to report seeing advanced-stage cancers among their patients than those at university-affiliated clinics. What’s more, PPE shortages and pandemic-related treatment interruptions were also more common at private practices, according to ASTRO.

In other findings, telemedicine is being used by 85% of clinics for follow-up visits and by 54% for new patient consultations, the society said. Only 12% used telemedicine for clinician assessments of patients undergoing radiation treatments, however.

Financial and operational challenges caused by the pandemic have continued to linger, ASTRO noted. Patient volume declined by an average of 73% at clinics and visits dropped by an average of 21%. In addition, 72% of practices had reduced staff at some point during the pandemic, according to the organization.

However, 100% of the responding physicians said that their radiation therapy networks remained open during multiple spikes of the pandemic. Only 7% closed any satellite locations, ASTRO said.

USPSTF’s 2016 CT colonography (Virtual Colonoscopy) guidance boosts screening rates by 50%

USPSTF’s 2016 CT colonography guidance boosts screening rates

By AuntMinnie.com staff writers

March 25, 2021 — The 2016 update by the U.S. Preventive Services Task Force (USPSTF) of its CT colonography (CTC) guidance boosted CT colonography screening rates by 50%, according to a study conducted by the Harvey L. Neiman Health Policy Institute and published March 19 in the American Journal of Preventive Medicine.

The USPSTF included CTC on its list of recommended tests for colorectal cancer in June 2016. A team led by Steve Chen of Emory University in Atlanta used commercial claims data from between 2010 and 2018 to examine the effects of this update on monthly CTC use rates in privately insured patients 50 to 64 years of age. During the study timeframe, 3,773 screening CT colonography scans were conducted in 31.2 million individuals.

The use rate of CTC increased from 0.4 to 0.6 scans per 100,000 people after the USPSTF’s 2016 recommendation — a boost of 50%, the group found.

“The release of supportive evidence-based recommendations by a recognized credible body was associated with an immediate increase in CTC use for colorectal cancer screening,” said senior author Michal Horný, PhD, also at Emory, in a statement released by Neiman Health Policy Institute. “The results of our study support the power of evidence-based recommendations to impact cancer screening rates among the U.S. privately insured population.”

CT exam encounters could boost colorectal cancer screening adherence

CT exam encounters could boost colorectal cancer screening adherence

By Kate Madden Yee, AuntMinnie.com staff writer

March 25, 2021 — Patients who are getting general CT exams could also be offered the opportunity for colorectal cancer (CRC) screening, thus improving colon screening rates, according to a study published in the May-June issue of Current Problems in Diagnostic Radiology.

Using CT as a tool to leverage colon screening could boost the health of subgroups of patients who may not be getting the preventive care they need, wrote a team led by Dr. Anand Narayan, PhD, of Massachusetts General Hospital in Boston.

“CT appointments may represent opportunities to improve overall colorectal cancer screening rates with CT colonography or other CRC screening methods among patients who have not received recommended screening,” the group wrote. “Prior studies have suggested that offering patients a wide variety of CRC screening options improves adherence, particularly among racial and/or ethnic minority groups.”

Second-leading cause of cancer death

Colorectal cancer is the second-leading cause of cancer-related death in the U.S., but screening uptake could use improvement, Narayan and colleagues noted. Previous studies have shown that particular patient subgroups — like racial/ethnic minorities and those without insurance — are less likely to be up to date on colorectal cancer screening, and therefore more likely to present with advanced disease. Barriers include fear or worry about getting screened and financial or logistical challenges.

But many patients undergo CT imaging each year, and CT colonography has shown high sensitivity for detecting polyps in the colon larger than 1 cm, according to the group. That’s why viewing CT exams as an opportunity to screen for colorectal cancer could be good medicine.

“Patients who have experience undergoing CT scans may be more likely to adhere to colorectal cancer screening recommendations if they get screened with a modality (CT colonography) that they are already familiar with,” the investigators wrote.

Narayan and colleagues sought to assess how many patients had undergone CT imaging but had not received recommended CRC screening, and to determine whether particular patient factors are associated with increased or decreased colon cancer screening rates.

The team used data from the 2015 National Health Interview Survey, including 16,206 survey respondents between the ages of 45 and 75 with no history of colorectal cancer screening (Curr Probl Diagn Radiol, May-June 2021, Vol. 50:3, pp. 332-336).

Of the total survey cohort, 50.8% underwent some form of colorectal cancer screening and 44.3% reported having received a CT scan. Among those who had a CT exam, 66.2% reported undergoing CRC screening of some kind; among those who did not receive colorectal cancer screening, 33.7% had undergone CT — which translates to an estimated 15.3 million people across the U.S., the authors noted.

The team found that statistically significant factors associated with CRC screening included higher levels of household income and education were associated with higher odds of colorectal cancer screening adherence, while being Asian and not having insurance were associated with lower odds.

Odds ratios for adherence to CRC screening among people who have undergone CT 
Patient characteristic Odds ratio P-value
Education
Less than college 1
College or more 1.2 0.012
Income
Household income 1 < 0.001
Insurance status
Insured 1
Uninsured 0.51 < 0.001
Race/ethnicity
Black 1.19 0.10
White 1
Hispanic 0.88 0.32
Other 0.62 0.16
Asian 0.5 0.001

“Our study results demonstrate that among patients who have not received recommended CRC screening, nearly one out of three report having undergone a CT examination, representing an estimated 15 million people across the United States,” the team wrote.

Take the opportunity

Imaging offers an opportunity to improve population health overall, according to Narayan and colleagues. It’s been shown, for example, that women presenting for breast cancer screening can also be screened for intimate partner violence and lung cancer.

In similar fashion, CT exam intake questionnaires could be used to assess whether patients eligible for colorectal cancer screening have undergone it, and radiology practices could educate these patients on CRC screening options. They could also use strategies like phone calls to patients, point-of-care reminders to providers, guidance from patient navigators, and community outreach workers.

“Radiology practices may consider adopting interventions outside of radiology that have been used successfully to increase cancer screening rates,” the authors concluded. “Prior studies have suggested that multifaceted, personalized approaches including a variety of outreach strategies are most likely to be successful. Radiology practices can work with other specialties to implement some of these interventions as part of coordinated strategies to improve screening adherence.”

Chest CT Scans show promise for monitoring health of obese patients

Thoracic CT shows promise for monitoring health of obese patients

By Kate Madden Yee, AuntMinnie.com staff writer

March 8, 2021 — Thoracic CT shows promise as an imaging modality that could help clinicians monitor the health of their obese patients, according to a presentation delivered March 5 at the virtual ECR.

In a session that addressed the use of imaging for visualizing obesity, Dr. Susan Copley of Imperial College Healthcare NHS Trust London shared clinical results that highlight the key role CT could play in monitoring the risk of cardiovascular disease in obese patients.

The World Health Organization defines obese individuals as those having a body mass index over 30 kg/m2, and it warns that being obese is a major risk factor for diabetes, cardiovascular disease, and cancer, Copley said. The prevalence of obesity is increasing worldwide; in the U.K. in 2018, 28% of the adult population had a BMI greater than 30, she noted.

And the condition has come into sharp focus during the COVID-19 pandemic, as obesity’s effects on the lungs increase the risk that those with COVID-19 could die from the illness — likely due to higher levels of inflammatory cytokines and lower levels of adiponectin, a hormone that protects the lungs from injury, in obese people.

“A BMI of 35 to 40 increases a COVID-19 patient’s risk of dying by 40%,” Copley said. “A BMI of more than 40 increases that risk to 90%.”

Copley referred to a study she and colleagues conducted in 2016 that was published in European Radiology that tracked 296 patients who underwent CT pulmonary angiography (CTPA) for pulmonary embolism. The study found that the shape and area of the posterior tracheal wall correlated with increasing subcutaneous fat thickness.

She also referred to a study she and a team conducted last year that was published in Radiology that used CT to assess lung parenchymal and tracheal morphology before and six months after patients underwent bariatric surgery. This investigation showed that particular imaging abnormalities improved after patients lost weight.

Imaging features in obese patients before and after bariatric surgery
Imaging feature Before surgery 6 months after surgery
Mosaic attenuation 33.3% 13.7%
End-expiratory air trapping 92.2% 29.4%
Tracheal area 201 mm2 229 mm2

“CT extent of air trapping correlates most with decreased lung capacity in obese people, [and improvement in] air trapping was the main determinant for decreased dyspnea following surgery,” she said.

Going forward, CT could be an effective way to assess risk in obese patients, according to Copley.

“Lung function may have a prognostic importance in obesity, and can be readily seen on CT,” she said. “Other imaging markers like hepatic steatosis [could also be useful], as could incorporating imaging data into deep learning algorithms for individualized risk assessment in obese individuals for cardiovascular and malignancy complications.”

Virtual Colonoscopy (CTColonography) is most effective way to detect advanced neoplasia (cancer)

CTC is most effective way to detect advanced neoplasia

By Kate Madden Yee, AuntMinnie.com staff writer

March 12, 2021 — CT colonography (CTC) with a polyp size threshold of ≥ 10 mm is more effective than multitarget stool DNA and fecal immunochemical testing for diagnosing advanced neoplasia, according to a study published online March 11 in the American Journal of Roentgenology.

The results could help patients avoid unnecessary colonoscopies, according to a team led by Dr. Perry Pickhardt of the University of Wisconsin in Madison.

“Among noninvasive CRC screening tests, CTC with ≥ 10-mm threshold most effectively targets advanced neoplasia, preserving detection while also decreasing unnecessary colonoscopies compared with multitarget stool DNA and fecal immunochemical testing,” the group wrote.

Noninvasive ways to screen for colorectal cancer include multitarget stool DNA, fecal immunochemical, and CTC testing, all of which can help patients avoid unnecessary colonoscopies. But the performance of these tests hasn’t been adequately compared, Pickhardt and colleagues noted.

“These noninvasive screening tests differ in their ability to detect advanced neoplasia [which may include advanced adenomas, high-risk serrated lesions, and invasive cancer], and these diagnostic performance differences must be balanced against other features such as cost, safety, and patient acceptance,” they wrote.

To evaluate the various types of colorectal screening tests, Pickhardt et al performed a literature review of 10 multitarget stool DNA, 27 CTC, and 88 fecal immunochemical testing studies that included data from a total of 2.4 million asymptomatic adults. The investigators evaluated each test’s positivity rate — which would lead to colonoscopy — as well as their positive predictive value and detection rates for both advanced neoplasia and colorectal cancer.

The team found that the performance of colorectal cancer screening for advanced neoplasia was highest with CTC at a 10-mm polyp size threshold.

Comparison of performance of noninvasive colorectal screening tests
Multitarget stool DNA Fecal immunochemical testing CTC at 6-mm polyp size threshold CTC at 10-mm polyp size threshold
Test positivity rate (= to optical colonoscopy referral rate) 13.5% 6.4% 13.4% 6.6%
Positive predictive value
Advanced neoplasia 26.9% 31.8% 34.4% 61%
Colorectal cancer 2.4% 4.9% 3.5% 6%
Detection rate
Advanced neoplasia 3.4% 2% 4.8% 4%
Colorectal cancer 0.31% 0.33% 0.46% 0.46%

Despite the study results, the investigators acknowledged that effective colorectal cancer screening may come down to patient preference.

“Each colorectal cancer screening option has relative advantages and disadvantages that should be carefully considered and tailored to the individual,” they concluded. “In the end, the ‘best’ test may be the one that the patient is willing to undergo.”