RSNA’s QIBA: A Quantitative Success

The Quantitative Imaging Biomarkers Alliance breaks ground in precision medicine


Carolyn Meltzer, headshot
Meltzer
Guimaraes
Guimaraes
Obuchowski
Obuchowski
Timothy Hall
Hall
Zahlmann
Zahlmann

Since 2007, RSNA’s Quantitative Imaging Biomarkers Alliance’s (QIBA) has been dedicated to advancing quantitative imaging — often considered the next frontier in radiology.

Over the years, QIBA has greatly expanded its membership, made enormous strides toward reaching the ultimate goal of improving patient care through precision medicine, and earned an international reputation for its groundbreaking work.

“I have been very pleased to watch the steady and painstaking progress of QIBA over the years to systematically advance quantitative imaging in medicine,” said Carolyn C. Meltzer, MD, RSNA Board of Directors liaison for science and the William P. Timmie Professor and Chair of the Department of Radiology and Imaging Sciences at Emory University School of Medicine in Atlanta. “This is a critically important goal to ensure the continuous innovation and enhanced value of the radiologist in this time of increasing complexity in health care.”

Quantitative imaging has enormous potential for revolutionizing research and treatment across a range of diseases and conditions, including cancer, cardiovascular and neurological disease. And while there are still a number of challenges, there is also potential for QIBA to play a role in an everyday radiology practice.

QIBA Profiles Validate Biomarkers

So what is the role of QIBA? Specifically, the researchers, health care professionals and industry stakeholders who make up QIBA have one mission: improving the value and practicality of quantitative imaging biomarkers by reducing variability across devices, sites, patients and time.

But there is a challenge in getting imaging stakeholders — whether radiologists, clinical trial investigators, or regulators — to accept the validity of quantitative imaging biomarkers in terms of affecting decision making, said QIBA Chair Alexander R. Guimaraes, MD, PhD, professor of radiology at the Oregon Health Sciences University, Portland.

To that end, QIBA creates profiles — documents that tells users what quantitative results can be achieved by following a particular profile.

“A profile is really the deliverable for QIBA,” Dr. Guimaraes said. “The process specifies what should be achieved and how to achieve it.”

The profile includes input from all actors in the imaging chain necessary to standardize the methods needed to create biomarkers that are accurate and reproducible.

“For example, after I’ve done my trial, how do I measure the treatment effect?” said Nancy Obuchowski, PhD, vice chair of the Department of Quantitative Health Sciences at the Cleveland Clinic. “I need to know the precision and bias of the measurement that we’re using as an endpoint, and if that endpoint is the quantitative imaging biomarker, then we need to know its precision and bias.

“If I’m going to run a clinical trial and use a quantitative imaging biomarker as my endpoint, I can compare two groups better if I can measure that biomarker more precisely,” she continued. “If there is a lot of noise in my measurements, then I need more patients to figure out whether that treatment worked.”

This also applies to cross-sectional studies where the doctor can identify patients who will benefit most from being included in the trial, Dr. Obuchowski said.

“So, if I can measure their baseline values more precisely, then I can be more confident in saying yes, these patients should be in the trial,” Dr. Obuchowski said.

While it reduces the sample size, it also makes the trial run more efficiently because physicians can use the biomarker to determine who is eligible for the study.

“Therefore, you are actually impacting dollars and drug development,” Dr. Guimaraes said.

Profiles also aid manufacturers in demonstrating compliance, said QIBA Co-Chair Timothy Hall, PhD, with the Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin-Madison.

“The imaging system itself has specific capabilities that are required and the profile defines what those are and what those performance criteria are so that manufacturers can demonstrate they are compliant,” Dr. Hall said.

A number of profiles are currently in development, including several technically confirmed profiles such as CT Tumor Volume Change for Advanced Disease and FDG-PET/CT as an Imaging Biomarker Measuring Response to Cancer Therapy.

"A profile is really the deliverable for QIBA. The process specifies what should be achieved and how to achieve it.” 

ALEXANDER R. GUIMARAES, MD, PHD

Achieving QIBA Profile Conformance

One of the latest developments is the establishment of new conformance testing services and self-attestation procedures for organizations seeking to establish conformance in a given QIBA profile.

“If a lab site is really interested in becoming a QIBA profile conformant, QIBA provides the profile plus a conformance statement checklist and an explanation of the process,” said QIBA Vice-Chair Gudrun Zahlmann, PhD, an independent consultant based in Germany.

Clinical sites or contract research organizations (CROs) that achieve QIBA profile specifications for a given profile can receive a conformance mark, which can be used to distinguish it as performing quantitative imaging studies with high levels of precision.

QIBA’s Potential for Everyday Radiology

Radiologists might wonder how QIBA is relevant to their everyday practice.

“The challenge that we face with QIBA is that most radiologists, with few exceptions, only use a handful of numbers, or quantitative imaging biomarkers, within their day-to-day practice,” Dr. Guimaraes said.

Yet there is potential for QIBA to play a role in the day-to-day radiology practice, he added. For example, diffusion-weighted imaging is used on a daily basis to influence the practice of prostate MRI. Radiologists tend to rely on the qualitative assessment of the diffusion-weighted image rather than the apparent diffusion coefficient, he said, which is the quantitative imaging biomarker.

“And the reason is that we have seen that the variability is actually high in that number,” Dr. Guimaraes added. “All actors in the imaging chain play a large role in the development of a profile, from the developers of modalities and devices to the technologists and radiologists who conduct and interpret exams,” he said.

“If each actor correctly performs their role, then the number that is derived can be relied upon — like an assay or blood test, because it has a small measurement error,” Dr. Guimaraes continued.

While it would be difficult, Dr. Guimaraes also believes that QIBA can be relevant at all levels of clinical practice, not just in academic settings, and not just for radiologists.

“The challenge is the practicality of implementing that level of rigor at a private practice,” he said. “What is the cost/benefit? Is the benefit of a diagnosis going to outweigh the cost of implementing this level of rigor for the radiologists or other clinicians utilizing the imaging biomarker? What would the cost be to the whole workflow?”

QIBA Recognized by CMS

Quantitative imaging can provide a benchmark for quality in imaging, which may translate to improved reimbursement. Some examples of quantitative imaging biomarkers and QIBA profiles have been recognized by the U.S. Centers for Medicare and Medicaid Services (CMS).

“CMS now has separate billing codes for MR elastography for the assessment of liver stiffness, which is a surrogate for cirrhosis and fibrosis of the liver, and underlying liver disease,” Dr. Guimaraes said.

This provides an opportunity for QIBA to play a role in terms of assessing a clinical site performing MR elastography, he added.

“And this creates a potential role for CMS to ask if you are using the QIBA profile, which has been vetted and written by the experts in the field,” Dr. Guimaraes said. “And if you are, there is confidence that you are not only doing it correctly in a standardized approach, but also that the values coming out, and the resulting management decisions, are actually correct.”

“So that’s a pathway that makes sense from all perspectives, for both the academic and nonacademic sites,” Dr. Guimaraes added. “As CMS works to improve quality across the board, we feel that QIBA is in a good space to guide them through this process.”

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