(Press-News.org) Baltimore, Md. (Embargoed until 12:30 p.m. EDT, June 8, 2015) - Imaging lung cancer requires both precision and innovation. With this aim, researchers have developed a technique for clinical positron emission tomography (PET) imaging that creates advanced whole-body parametric maps, which allow quantitative evaluation of tumors and metastases throughout the body, according to research announced at the 2015 Annual Meeting of the Society of Nuclear Medicine and Molecular Imaging (SNMMI).
Scientists have developed a novel agent for cancer imaging that seeks and attaches to integrin in the body. Biochemically, integrin facilitates cellular signaling and that makes it ideal for imaging growing and metastatic tumors that have spread through blood or lymph to settle in other organs. The imaging agent, also called a radiotracer, combines a small dose of medical radionuclides, in this case gallium-68 (Ga-68), and a peptide that has a natural affinity for integrin called arginine-glycine-aspartic acid (RGD). The integrin expression in the tumor lesions can be quantified by key parameters derived from dynamic PET imaging.
Currently, clinical PET scanners have a one-bed position with a limited field of view, so dynamic scans can provide moving images of tracer uptake in only a small frame of less than a foot. They are not able to evaluate molecular targets in cancer patients with multiple metastatic lesions distributed in a range greater than that single-position field of view. In the newly developed technique, the imaging bed shuttles between different positions in each timeframe to capture metastases throughout the whole body.
Once image data have been acquired, specialized software is then used to reconstruct the dynamic image series, followed by quantitative analysis that calculates important parameters about the function of the imaging agent inside the body.
"For patients with multiple tumors, this technology could significantly improve the contrast and quantitation of their PET scans and, therefore, the quality of their care," said Ning Guo, PhD, a research fellow in the department of radiology at Massachusetts General Hospital and Harvard Medical School in Boston, Mass. "RGD imaging could contribute to earlier diagnosis and more accurate prognosis by not only discriminating between benign tumors, inflammation and malignancy but also providing insight about malignant lesions that are atypical or unclear - a common challenge when using FDG-PET."
For this study, 16 lung cancer patients were imaged using whole-body dynamic RGD-PET, including acquisition of data from four different bed positions during an hour-long scan. The resulting quantitative analysis and parametric maps cover both primary tumors in the lung and scattered metastases. The researchers used software for image reconstruction and then calculated a number of parameters, including standardized uptake value (SUV) and kinetic parameter (binding potential), which provide information about how much the agent is being taken into the tissues and how strongly it is binding to targets. Parametric maps of binding potential not only showed a six-fold increase in tumor-to-muscle ratio and significant spikes in the contrast between tumor and background when compared to static PET scans, they also provided pixel-wise quantitation of both primary and distant metastatic tumor integrin expression.
Upon further study and pending regulatory approval, this method of PET imaging could be translated to clinical imaging for lung cancer and it has the potential to be used to detect a range of other cancers.
Approximately 221,200 new cases of lung cancer will be diagnosed in the U.S. and 158,040 patients will die from the disease in 2015, according to estimates from the American Cancer Society.
INFORMATION:
Scientific Paper 122: "Whole-body Parametric Imaging of Lung Cancer Patients with 68Ga-PRGD2," N. Guo, M. Wang, G. El Fakhri, Q. Li, Center for Advanced Medical Imaging Sciences, Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Mass.; K. Zheng, F. Li, Z. Zhu, Department of Nuclear Medicine, Peking Union Medical College Hospital, Beijing, China; X. Chen, NIBIB, National Institutes of Health, Bethesda, Md.; SNMMI's 62nd Annual Meeting, June 6-10, 2015, Baltimore, Md.
About the Society of Nuclear Medicine and Molecular Imaging
The Society of Nuclear Medicine and Molecular Imaging (SNMMI) is an international scientific and medical organization dedicated to raising public awareness about nuclear medicine and molecular imaging, a vital element of today's medical practice that adds an additional dimension to diagnosis, changing the way common and devastating diseases are understood and treated and helping provide patients with the best health care possible.
SNMMI's 18,000 members set the standard for molecular imaging and nuclear medicine practice by creating guidelines, sharing information through journals and meetings and leading advocacy on key issues that affect molecular imaging and therapy research and practice. For more information, visit http://www.snmmi.org.
Baltimore, Md. (Embargoed until 12:30 p.m. EDT, June 8, 2015) - A first-in-human study revealed at the 2015 Annual Meeting of the Society of Nuclear Medicine and Molecular Imaging (SNMMI) shows how a powerful new drug finds and attaches itself to the ovarian and prostate cancer cells for both imaging and personalized cancer treatment.
The targeted aspect of the imaging agent, called I-124 PEG-AVP0458, is a small protein (avibody) linked to polyethylene glycol (PEG) chains. The drug compound is then labeled with the radionuclide iodine-124. Drugs like PEG-AVP0458 are ...
Baltimore, Md. (Embargoed until 12:30 p.m. EDT, June 8, 2015) - Non-Hodgkin lymphoma (NHL), a potentially devastating cancer of the blood and immune system, can range from relatively easy to treat to very aggressive. For more aggressive cases, post-treatment surveillance with molecular imaging could mean the early start of a new, life-saving treatment, say researchers presenting during the 2015 Annual Meeting of the Society of Nuclear Medicine and Molecular Imaging (SNMMI).
NHL is the fifth most prevalent cancer in America, according to lead author Mehdi Taghipour, MD, ...
Baltimore, Md. (embargoed until 12:30 p.m. EDT, June 8, 2015) - Research presented at the 2015 Annual Meeting of the Society of Nuclear Medicine and Molecular Imaging (SNMMI) shows how a new molecular imaging agent finds prostate cancer that has spread to other tissues by locking in on an enzyme called prostate specific membrane antigen (PSMA), associated with prostate cancer.
"To date, conventional imaging is limited in detecting prostate cancer metastasis accurately and measurably," said Neeta Pandit-Taskar, MD, co-author of the study and a researcher at Memorial Sloan ...
A recently developed tool can accurately predict the risk of death for patients within 1 year after admission to hospital using routinely collected data, reports a study in CMAJ (Canadian Medical Association Journal).
"An accurate assessment of risk of death, particularly if that risk is high, could motivate and inform discussions between patients and physicians regarding goals of care," states Dr. Carl van Walraven, a researcher at the Ottawa Hospital and the University of Ottawa, Ottawa, Ontario, who developed the tool.
Researchers in Canada and the United States ...
Baltimore, Md. -- Scientists are taking medical imaging research and drug discovery to a new level by developing a molecular imaging system that combines several advanced technologies for all-in-one imaging of both tissue models and live subjects, say presenters at the 2015 annual meeting of the Society of Nuclear Medicine and Molecular Imaging (SNMMI).
The preclinical and intra-vital molecular imaging system houses a window for tissue observation in addition to a larger imaging chamber. Together they are being used to peer into the microenvironment of tumors and other ...
Baltimore, Md. (Embargoed until 12:30 p.m., June 8, 2015) - The origin of cancer is often obscured by metastases--tumors that have already spread to other tissues. This is especially the case for neuroendocrine tumors (NETs), a malignancy of nerve cells scattered throughout various organ systems that are sensitive to the signaling of neurotransmitters and hormones. An investigational molecular imaging technique could be the key to finding the elusive primary tumor, say presenters at the 2015 Annual Meeting of the Society of Nuclear Medicine and Molecular Imaging (SNMMI). ...
Baltimore, Md. -- A relatively new biomarker called prostate-specific membrane antigen (PSMA) is the bullseye for three new magnetic resonance imaging (MRI) agents that bind to the protein in not only prostate cancer, but a range of tumor types, according to research unveiled at the 2015 annual meeting of the Society of Nuclear Medicine and Molecular Imaging (SNMMI).
'We have shown in this proof-of-concept study that PSMA could serve as a biomarker for MR-based molecular imaging due to its high concentration within target cells, limited expression within non-targeted ...
Baltimore, Md. -- Amyloid build-up is commonly talked about in relation to Alzheimer's disease, but amyloidosis can be found throughout the body. An excessive accumulation of these insoluble proteins could cause a heart attack or even death. A new molecular imaging scan of amyloid in the heart could help diagnose the problem, say researchers at the 2015 annual meeting of the Society of Nuclear Medicine and Molecular Imaging (SNMMI).
The condition is called transthyretin-type (TTR) amyloidosis after the TTR gene thought to cause the over-abundance of plaque build-up. ...
Baltimore, Md. -- New research presented during the 2015 annual meeting of the Society of Nuclear Medicine and Molecular Imaging (SNMMI) demonstrates that amyloid positron emission tomography (amyloid PET) scans of the brain provide clearer diagnosis and earlier, more effective treatment for Alzheimer's patients, when results of a more conventional PET scan remain ambiguous.
Researchers reviewed the clinical outcomes of two kinds of PET scans: a preliminary scan with a common radiotracer called fluorodeoxyglucose (FDG), which acts like glucose in the brain to capture ...
Baltimore, Md. -- Fatal cardiac events are often preceded by abnormal blood clots, also called thrombosis. Scientists have now developed a molecular imaging technique that could save lives by revealing troublesome thrombi, according to a study presented at the 2015 annual meeting of the Society of Nuclear Medicine and Molecular Imaging (SNMMI).
'Thrombosis is the underlying cause of deadly diseases such as stroke, pulmonary embolism, deep vein thrombosis and heart attack, which affect millions of people worldwide,' said Francesco Blasi, Ph.D., lead author of the study ...