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Imaging-guided cancer treatment


Imaging-guided cancer treatment

Writer & reporter: Dror Nir, PhD

It is estimated that the medical imaging market will exceed $30 billion in 2014 (FierceMedicalImaging). To put this amount in perspective; the global pharmaceutical market size for the same year is expected to be ~$1 trillion (IMS) while the global health care spending as a percentage of Gross Domestic Product (GDP) will average 10.5% globally in 2014 (Deloitte); it will reach ~$3 trillion in the USA.

Recent technology-advances, mainly miniaturization and improvement in electronic-processing components is driving increased introduction of innovative medical-imaging devices into critical nodes of major-diseases’ management pathways. Consequently, in contrast to it’s very small contribution to global health costs, medical imaging bears outstanding potential to reduce the future growth in spending on major segments in this market mainly: Drugs development and regulation (e.g. companion diagnostics and imaging surrogate markers); Disease management (e.g. non-invasive diagnosis, guided treatment and non-invasive follow-ups); and Monitoring aging-population (e.g. Imaging-based domestic sensors).

In; The Role of Medical Imaging in Personalized Medicine I discussed in length the role medical imaging assumes in drugs development.  Integrating imaging into drug development processes, specifically at the early stages of drug discovery, as well as for monitoring drug delivery and the response of targeted processes to the therapy is a growing trend. A nice (and short) review highlighting the processes, opportunities, and challenges of medical imaging in new drug development is: Medical imaging in new drug clinical development.

The following is dedicated to the role of imaging in guiding treatment.

Precise treatment is a major pillar of modern medicine. An important aspect to enable accurate administration of treatment is complementing the accurate identification of the organ location that needs to be treated with a system and methods that ensure application of treatment only, or mainly to, that location. Imaging is off-course, a major component in such composite systems. Amongst the available solution, functional-imaging modalities are gaining traction. Specifically, molecular imaging (e.g. PET, MRS) allows the visual representation, characterization, and quantification of biological processes at the cellular and subcellular levels within intact living organisms. In oncology, it can be used to depict the abnormal molecules as well as the aberrant interactions of altered molecules on which cancers depend. Being able to detect such fundamental finger-prints of cancer is key to improved matching between drugs-based treatment and disease. Moreover, imaging-based quantified monitoring of changes in tumor metabolism and its microenvironment could provide real-time non-invasive tool to predict the evolution and progression of primary tumors, as well as the development of tumor metastases.

A recent review-paper: Image-guided interventional therapy for cancer with radiotherapeutic nanoparticles nicely illustrates the role of imaging in treatment guidance through a comprehensive discussion of; Image-guided radiotherapeutic using intravenous nanoparticles for the delivery of localized radiation to solid cancer tumors.

 Graphical abstract

 Abstract

One of the major limitations of current cancer therapy is the inability to deliver tumoricidal agents throughout the entire tumor mass using traditional intravenous administration. Nanoparticles carrying beta-emitting therapeutic radionuclides [DN: radioactive isotops that emits electrons as part of the decay process a list of β-emitting radionuclides used in radiotherapeutic nanoparticle preparation is given in table1 of this paper.) that are delivered using advanced image-guidance have significant potential to improve solid tumor therapy. The use of image-guidance in combination with nanoparticle carriers can improve the delivery of localized radiation to tumors. Nanoparticles labeled with certain beta-emitting radionuclides are intrinsically theranostic agents that can provide information regarding distribution and regional dosimetry within the tumor and the body. Image-guided thermal therapy results in increased uptake of intravenous nanoparticles within tumors, improving therapy. In addition, nanoparticles are ideal carriers for direct intratumoral infusion of beta-emitting radionuclides by convection enhanced delivery, permitting the delivery of localized therapeutic radiation without the requirement of the radionuclide exiting from the nanoparticle. With this approach, very high doses of radiation can be delivered to solid tumors while sparing normal organs. Recent technological developments in image-guidance, convection enhanced delivery and newly developed nanoparticles carrying beta-emitting radionuclides will be reviewed. Examples will be shown describing how this new approach has promise for the treatment of brain, head and neck, and other types of solid tumors.

The challenges this review discusses

  • intravenously administered drugs are inhibited in their intratumoral penetration by high interstitial pressures which prevent diffusion of drugs from the blood circulation into the tumor tissue [1–5].
  • relatively rapid clearance of intravenously administered drugs from the blood circulation by kidneys and liver.
  • drugs that do reach the solid tumor by diffusion are inhomogeneously distributed at the micro-scale – This cannot be overcome by simply administering larger systemic doses as toxicity to normal organs is generally the dose limiting factor.
  • even nanoparticulate drugs have poor penetration from the vascular compartment into the tumor and the nanoparticles that do penetrate are most often heterogeneously distributed

How imaging could mitigate the above mentioned challenges

  • The inclusion of an imaging probe during drug development can aid in determining the clearance kinetics and tissue distribution of the drug non-invasively. Such probe can also be used to determine the likelihood of the drug reaching the tumor and to what extent.

Note: Drugs that have increased accumulation within the targeted site are likely to be more effective as compared with others. In that respect, Nanoparticle-based drugs have an additional advantage over free drugs with their potential to be multifunctional carriers capable of carrying both therapeutic and diagnostic imaging probes (theranostic) in the same nanocarrier. These multifunctional nanoparticles can serve as theranostic agents and facilitate personalized treatment planning.

  • Imaging can also be used for localization of the tumor to improve the placement of a catheter or external device within tumors to cause cell death through thermal ablation or oxidative stress secondary to reactive oxygen species.

See the example of Vintfolide in The Role of Medical Imaging in Personalized Medicine

vinta

Note: Image guided thermal ablation methods include radiofrequency (RF) ablation, microwave ablation or high intensity focused ultrasound (HIFU). Photodynamic therapy methods using external light devices to activate photosensitizing agents can also be used to treat superficial tumors or deeper tumors when used with endoscopic catheters.

  • Quality control during and post treatment

For example: The use of high intensity focused ultrasound (HIFU) combined with nanoparticle therapeutics: HIFU is applied to improve drug delivery and to trigger drug release from nanoparticles. Gas-bubbles are playing the role of the drug’s nano-carrier. These are used both to increase the drug transport into the cell and as ultrasound-imaging contrast material. The ultrasound is also used for processes of drug-release and ablation.

 HIFU

Additional example; Multifunctional nanoparticles for tracking CED (convection enhanced delivery)  distribution within tumors: Nanoparticle that could serve as a carrier not only for the therapeutic radionuclides but simultaneously also for a therapeutic drug and 4 different types of imaging contrast agents including an MRI contrast agent, PET and SPECT nuclear diagnostic imaging agents and optical contrast agents as shown below. The ability to perform multiple types of imaging on the same nanoparticles will allow studies investigating the distribution and retention of nanoparticles initially in vivo using non-invasive imaging and later at the histological level using optical imaging.

 multi

Conclusions

Image-guided radiotherapeutic nanoparticles have significant potential for solid tumor cancer therapy. The current success of this therapy in animals is most likely due to the improved accumulation, retention and dispersion of nanoparticles within solid tumor following image-guided therapies as well as the micro-field of the β-particle which reduces the requirement of perfectly homogeneous tumor coverage. It is also possible that the intratumoral distribution of nanoparticles may benefit from their uptake by intratumoral macrophages although more research is required to determine the importance of this aspect of intratumoral radionuclide nanoparticle therapy. This new approach to cancer therapy is a fertile ground for many new technological developments as well as for new understandings in the basic biology of cancer therapy. The clinical success of this approach will depend on progress in many areas of interdisciplinary research including imaging technology, nanoparticle technology, computer and robot assisted image-guided application of therapies, radiation physics and oncology. Close collaboration of a wide variety of scientists and physicians including chemists, nanotechnologists, drug delivery experts, radiation physicists, robotics and software experts, toxicologists, surgeons, imaging physicians, and oncologists will best facilitate the implementation of this novel approach to the treatment of cancer in the clinical environment. Image-guided nanoparticle therapies including those with β-emission radionuclide nanoparticles have excellent promise to significantly impact clinical cancer therapy and advance the field of drug delivery.

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Minimally invasive image-guided therapy for inoperable hepatocellular carcinoma

Curator & Reporter: Dror Nir, PhD

Large organs like the liver are good candidates for focused treatment. The following paper:

Minimally invasive image-guided therapy for inoperable hepatocellular carcinoma: What is the evidence today?

By Beatrijs A. Seinstra1, et. al. published mid-2010, gives a review of the state-of-the-art of the then available methods for local lesions’ ablation. As far as ablation techniques availability, I have found this review very much relevant to today’s technological reality. It is worthwhile noting that in the last couple of years, new imaging-based navigation and guidance applications were introduced into the market holding a promise to improve the accuracy of administrating such treatment. These are subject to clinical validation in large clinical studies.  From the above mentioned publication I have chosen to highlight the parts discussing the importance of imaging-based guidance to the effective application of localized ablation-type therapies.

The clinical need:

Hepatocellular carcinoma (HCC) is a primary malignant tumor of the liver that accounts for an important health problem worldwide. Primary liver cancer is the sixth most common cancer worldwide with an incidence of 626,000 patients a year, and the third most common cause of cancer-related death [1]. Only 10–15% of HCC patients are suitable candidates for hepatic resection and liver transplantation due to the advanced stage of the disease at time of diagnosis and shortage of donors.

Immerging solution:

In order to provide therapeutic options for patients with inoperable HCC, several minimally invasive image-guided therapies for locoregional treatment have been developed. HCC has a tendency to remain confined to the liver until the disease has advanced, making these treatments particularly attractive.

Minimally invasive image-guided therapies can be divided into the group of the tumor ablative techniques or the group of image-guided catheter-based techniques. Tumor ablative techniques are either based on thermal tumor destruction, as in radiofrequency ablation (RFA), cryoablation, microwave ablation, laser ablation and high-intensity focused ultrasound (HIFU), or chemical tumor destruction, as in percutaneous ethanol injection (PEI). These techniques are mostly used for early stage disease. Image-guided catheter-based techniques rely on intra-arterial delivery of embolic, chemoembolic, or radioembolic agents [22]. These techniques enable treatment of large lesions or whole liver treatment, and are as such used for intermediate stage HCC (Figure 1).

Minimally invasive image-guided ablation techniques and intra-arterial interventions may prolong survival, spare more functioning liver tissue in comparison to surgical resection (which can be very important in cirrhotic patients), allow retreatment if necessary, and may be an effective bridge to transplantation [2327].

During the last 2 decades, minimally invasive image-guided therapies have revolutionized the management of inoperable HCC.

The value of image guidance

Accurate imaging is of great importance during minimally invasive loco-regional therapies to efficiently guide and monitor the treatment. It enables proper placement of instruments, like the probe in case of ablation or the catheter in case of intra-arterial therapy, and accurate monitoring of the progression of the necrotic zone during ablation.

can all be employed. In current clinical practice, placement of the catheter in intra-arterial procedures is usually performed under fluoroscopic guidance, while ablation may be guided by ultrasound, CT or MRI.

  • Ultrasound guidance allows probe insertion from every angle, offers real time visualization and correction for motion artifacts when targeting the tumor, and is low cost. However, the gas created during ablation (or ice in the case of cryoablation) hampers penetration of the ultrasound beams in tissue, causing acoustic shadowing and obscuring image details like the delineation between tumor borders and ablation zone.
  • CT is also frequently used to guide minimally invasive ablation therapy, and is a reliable modality to confirm treatment results. In comparison to US, it provides increased lesion discrimination, a more reliable depiction of ablated/non-ablated interfaces, and a better correlation to pathologic size [28]. However, due to its hypervascularity, small HCCs can only be clearly visualized in the arterial phase for a short period of time. Another disadvantage of CT is the exposure of the patient and physician to ionizing radiation.
  • Combining US imaging for probe placement and CT for ablation monitoring reduces this exposure. At the moment, hybrid systems are being developed, enabling combination of imaging techniques, like ultrasound and CT imaging, thereby improving the registration accuracy during treatment [29]. The interest in MRI-guided ablation is growing, as it produces a high-quality image allowing high-sensitivity tumor detection and accurate identification of the target region with multiplanar imaging.
  • MRI also enables real-time monitoring of the temperature evolution during treatment [3035]. However, MRI is an expensive technique, and MRI-guided ablation is still limited in clinical practice. Currently, the most widely used ablation technique for percutaneous treatment of focal hepatic malignancies is radiofrequency ablation (RFA), which has been shown to be safe and effective for the treatment of early stage HCC [4850]. During RFA, a small electrode is placed within the tumor, and a high-frequency alternating electric current (approximately 400 MHz) is generated, causing ionic agitation within the tissue. ….. Most frequently ultrasound is used for image guidance (Figs. 23), but there are reports of groups who use CT, MRI, or fluoroscopic imaging.
Ultrasound guided RFA. a: HCC lesion in a non-surgical patient pre-treatment (pointed out by arrow). b: Just after start treatment, electrode placed centrally in the tumor. c: Gas formation during ablation causes acoustic shadowing

Ultrasound guided RFA. a: HCC lesion in a non-surgical patient pre-treatment (pointed out by arrow). b: Just after start treatment, electrode placed centrally in the tumor. c: Gas formation during ablation causes acoustic shadowing

Contrast-enhanced CT pre- and post-RFA. Same patient as in Fig. 2. a: Hypervascular lesion (biopsy proven HCC) in right liver lobe (pointed out by arrow) before treatment. b: Ablated lesion directly post ablation, with reactive hyperemia around the RFA lesion

Contrast-enhanced CT pre- and post-RFA. Same patient as in Fig. 2. a: Hypervascular lesion (biopsy proven HCC) in right liver lobe (pointed out by arrow) before treatment. b: Ablated lesion directly post ablation, with reactive hyperemia around the RFA lesion

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Other research papers related to the management of Prostate cancer were published on this Scientific Web site:

HBV and HCV-associated Liver Cancer: Important Insights from the Genome

Issues in Personalized Medicine in Cancer: Intratumor Heterogeneity and Branched Evolution Revealed by Multiregion Sequencing

Harnessing Personalized Medicine for Cancer Management, Prospects of Prevention and Cure: Opinions of Cancer Scientific Leaders @ http://pharmaceuticalintelligence.com

Whole-body imaging as cancer screening tool; answering an unmet clinical need?

Personalized Medicine: Cancer Cell Biology and Minimally Invasive Surgery (MIS)

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2013 – YEAR OF THE ULTRASOUND

Author – Writer: Dror Nir, PhD

To those of you who did not know, 2013 is the year of the ultrasound: http://www.ultrasound2013.org/. This initiative was launched by AIUM and its objectives:

  • Raise awareness of the value and benefits of ultrasound among patients, health care providers, and insurers
  • Provide ultrasound education and evidence-based guidelines for health care providers
  • Educate insurers about the cost savings and patient benefits associated with performing an ultrasound study when scientific evidence supports its potential effectiveness compared to other imaging modalities
  • Educate patients about the benefits of ultrasound as the appropriate imaging modality for their care
  • Encourage the incorporation of ultrasound into medical education

 Quoting from the ultrasound first web-site:

The initiative is designed to call attention to the safe, effective, and affordable advantages of ultrasound as an alternative to other imaging modalities that are more costly and/or emit radiation. For a growing number of clinical conditions, ultrasound has been shown to be equally effective in its diagnostic capability, with a distinct advantage in safety and cost over computed tomography and magnetic resonance imaging. Despite this advantage, evidence suggests that ultrasound is vastly underutilized. Ultrasound First focuses on educating health care workers, medical educators, insurers, and patients of the benefits of ultrasound in medical care. “There is growing support and public awareness for the need to reduce and carefully monitor patients’ exposure to radiation during medical imaging. The use of ultrasound as an alternative imaging modality will help achieve that goal while reducing cost,” states AIUM President Alfred Abuhamad, MD. “Many health care workers and insurers are unacquainted with the range of conditions for which ultrasound has been shown to have superior diagnostic capabilities. Disseminating this knowledge to health care workers and incorporating ultrasound in medical protocols where scientific evidence has shown its diagnostic efficacy will undoubtedly improve patient safety and reduce cost. The time to act is now.”

 A primary component of Ultrasound First is providing clinical evidence for the use of ultrasound. To that aim, the Journal of Ultrasound in Medicine has launched a special feature, the Sound Judgment Series, consisting of invited articles highlighting the clinical value of using ultrasound first in specific clinical diagnoses where ultrasound has shown comparative or superior value. Clinical conditions that will be addressed in the series include postmenopausal bleeding, right lower quadrant pain, pelvic pain, right upper quadrant pain, and shoulder pain, among others. This series will serve as an important educational resource for health care workers and educators.  On the clinical evidence page one can find reasoning for why ultrasound first. Not much related to cancer diagnosis and management. The only interesting claim is:Ultrasound-guided surgery: Its use to remove tumors from women who have palpable breast cancer is much more successful than standard surgery in excising all the cancerous tissue while sparing as much healthy tissue as possible.”

In support of this initiative The Journal of Ultrasound in Medicine has launched a special series, Sound Judgment, comprised of invited articles highlighting the clinical value of using ultrasound first in specific clinical diagnoses where ultrasound has shown comparative or superior value. So far it includes only two items related to management of cancer: Sonography of Facial Cutaneous Basal Cell Carcinoma, A First-line Imaging Technique; by Ximena Wortsman, MD, and Quantitative Assessment of Tumor Blood Flow Changes in a Murine Breast Cancer Model After Adriamycin Chemotherapy Using Contrast-Enhanced Destruction-Replenishment Sonography; by Jian-Wei Wang, MD et. al. The devoted readers of our Open Access Scientific Journal might find the article by Dr. Wortsman, MD bringing complementary information to a previous post of mine: Virtual Biopsy – is it possible?. Qouting from this article: “Cutaneous basal cell carcinoma is the most common cancer in human beings, and the face is its most frequent location. Basal cell carcinoma is rarely lethal but can generate a high degree of disfigurement. Of all imaging techniques, sonography has proven to support the diagnosis and provide detailed anatomic data on extension in all axes, the exact location, vascularity, and deeper involvement. This information can be used for improving management and the cosmetic results of patients.”

 The article gives clear presentation of the problem and includes demonstrative pictures:

f1

Figure: Basal cell carcinoma with dermal involvement (transverse view, nasal tip). Grayscale sonography (A) and 3-dimensional reconstruction (B, 5- to 8-second sweep) show a 10.1-mm (wide) × 1.4-mm (deep) well-defined hypoechoic oval lesion (between markers in A and outlined in B) that affects the dermis (d) of the left nasal wing. Notice the hyperechoic spots (arrowheads) within the lesion. The nasal cartilage (c) is unremarkable; asterisk indicates basal cell carcinoma.

Basal cell carcinoma with dermal and subcutaneous involvement (transverse view, frontal region). A, Grayscale sonography shows a 11.4-mm (wide) × 6.6-mm (deep) well-defined oval hypoechoic lesion that involves the dermis (d) and subcutaneous tissue (st). There are hyperechoic spots (arrowheads) within the tumor. B, Color Doppler sonography shows increased vascularity within the tumor (asterisk). C, Three-dimensional sonographic reconstruction (5- to 8-second sweep) highlights the lesion (asterisk, outlined); b indicates bony margin of the skull.

Basal cell carcinoma with dermal and subcutaneous involvement (transverse view, frontal region). A, Grayscale sonography shows a 11.4-mm (wide) × 6.6-mm (deep) well-defined oval hypoechoic lesion that involves the dermis (d) and subcutaneous tissue (st). There are hyperechoic spots (arrowheads) within the tumor. B, Color Doppler sonography shows increased vascularity within the tumor (asterisk). C, Three-dimensional sonographic reconstruction (5- to 8-second sweep) highlights the lesion (asterisk, outlined); b indicates bony margin of the skull.

f3

Figure: Pleomorphic presentations of basal cell carcinoma lesions on grayscale sonography (transverse views). Notice the variable shapes of the tumors.

f4

Figure: Frequently, blood flow can be detected within the tumor and its periphery, with slow-flow arteries or veins. The latter vascular data can orient the clinician about the distribution and amount of blood flow that he or she will face during surgery. Despite the fact that basal cell carcinomas usually do not present high vascularity, it should be kept in mind that many of basal cell carcinoma operations are performed in the offices of clinicians and not in the main operating rooms of large hospitals. Nevertheless, the finding of high vascularity within a clinically diagnosed basal cell carcinoma may suggest another type of skin cancer that could occasionally mimic basal cell carcinoma, such as squamous cell carcinoma, Merkel cell carcinoma, or a metastatic tumor. The above figure presents variable degrees of vascularity in basal cell carcinoma lesions going from hypovascular to hypervascular on color and power Doppler sonography (transverse views)

f5

Figure: The depth correlation between sonography (variable frequency) and histologic analysis in facial basal cell carcinoma has been reported to be excellent. Thus, the intraclass correlation coefficient for comparing thickness for the two methods (sonography and histologic analysis) that has been described in literature is 0.9 (intraclass correlation coefficient values ≥0.9 are very good; 0.70–0.89 are good; 0.50–0.69 are moderate; 0.30–049 are mediocre; and ≤0.29 are bad). Two rare sonographic artifacts have been described in basal cell carcinoma. One is the “angled border” that is produced by an inflammatory giant cell reaction underlying the tumor, which may falsely increase the apparent size of the tumor. The other is the “blurry border,” which is produced by large hypertrophy of the sebaceous glands surrounding the lesion. According to the literature, both artifacts can be recognized by a well-trained operator. The figure above presents the sonographic involvement of deeper layers such as the nasal cartilage and orbicularis muscles in the face is of critical importance and may change the decision about the type of surgery. Basal cell carcinoma with nasal cartilage involvement (3-dimensional reconstruction, 5- to 8-second sweep, transverse view, left nasal wing). Notice the extension of the tumor (asterisk, outlined) to the nasal cartilage region (c); d indicates dermis.

Basal cell carcinoma with involvement of the orbicularis muscle of the eyelid (m). Grayscale sonography (transverse view, right lower eyelid) shows that the tumor (asterisk) affects the muscle layer (arrows).

Basal cell carcinoma with involvement of the orbicularis muscle of the eyelid (m). Grayscale sonography (transverse view, right lower eyelid) shows that the tumor (asterisk) affects the muscle layer (arrows).

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Imaging guided Cancer-Therapy – a Discipline in Need of Guidance.

 Author – Writer: Dror Nir, PhD

The use of imaging in cancer management is broadly established. During the past two decades, advancements in imaging; image quality, precision and reproducibility lead to introduction of localized, minimally invasive treatments of cancer lesions.

 A statement-paper, published online: 17 January 2013: Radiologists’ leading position in image-guided therapy, which presents the thoughts of the Image-Guided Therapy Working Group within the Research Committee of the European Society of Radiology, give hope that the policy-makers in the European radiology society are becoming aware of the need to guide this process.

Although the authors are addressing imaging guided therapy (IGT) in its broad sense, most of their examples are related to treatment of cancer. The main reason for provided for being concerned with what is happening in this domain is: “This means that the planning, performing and monitoring, as well as the control of the therapeutic procedure, are based and dependent on the “virtual reality” provided by imaging investigations.”

The most interesting points raised by the authors are:

 1. The realization that IGT is involving many “non-radiologist”, and this fact cannot be ignored: “This role is mainly driven by the sophisticated opportunities offered by medical computing and radiological image guidance with regard to precision and minimal invasiveness [2]. However, the impact of radiology on the regulatory medico-legal, technical and radioprotection issues in this field have not yet been defined. Since an increasing number of procedures will probably be performed by non-radiologists, several main questions have to be addressed:

  • How should the radiology training requirements for non-radiologists be provided?
  • How should the technical and radioprotection related responsibilities for radiological imaging systems used by non-radiologists be organised?
  • How should radiologists be involved in the practical routine use of non-radiological image-guided procedures in clinical practice?

Considering the almost pan-European medical reality with decreasing staff resources and increasing diversification and subspecialisation, radiologists have to stress the fact that within a cooperative, goal-oriented and multidisciplinary environment, the specialty-specific knowledge should confer upon radiologists a significant impact on the overall responsibility for all imaging-related processes in various non-radiological specialties (such as purchase, servicing, quality management, radiation protection and documentation). Furthermore, radiologists should take responsibility for the definition and compliance with the legal requirements regarding all radiological imaging, especially if non-radiologists have to be trained in the use of imaging technology for guidance of therapy.”

2. Quality assurance and service standards needs to be established; “Performing IGT necessitates specific quality management tools for establishing standards and maintaining levels of excellence…. A European task force group on IGT might be necessary to further develop certification guidelines and establish requirements for IGT practice according to known standards, focused on common recommendations and certification guidelines.”

3. Controlling the process of introducing new medical devices into this niche-market: “IGT research can be broadly divided into two categories, target specific research (e.g. the type of tumour or vascular lesion by imaging biomarkers) and technical research (e.g. evaluation of a new device or procedure). Understanding the efficacy and application of new and emerging technologies is a critical first step, which then leads to target-specific research. The focus of this research is aimed at understanding when, where and in whom the therapy can provide clear clinical benefit and how to use IGT in conjunction with, or as an alternative to, more established therapies. This also clearly includes research on the development and implementation of imaging biomarkers, defined as objectively measured indicators of normal biological processes, pathological changes, or responses to a therapeutic intervention [9]…..

4. An unusual remark is made in respect to the way new devices are introduced: “Clinical specialists who lack the knowledge and expertise required to champion IGT and who are often already over-committed in pursuing their own research goals often dominate committees in control of other funding streams….”

5. Clear recognition that “health-care costs” is of outmost importance: “Demonstration of the cost effectiveness of IGT methods of treatment and targeting with formal quantification of financial as well as patient benefit would encourage their wider adoption. In a broad perspective, health technology assessment (HTA) might be the way for the systematic evaluation of health-relevant IGT procedures and methods, the effectiveness, safety and economic viability of a health intervention, as well as its social, ethical, legal and organisational effects; and for providing a basis for decisions in the health system.”

 References

1.

Solomon SB, Silverman SG (2010) Imaging in interventional oncology. Radiology 257(3):624–40PubMedCrossRef

2.

Levy MA, Rubin DL (2011) Current and future trends in imaging informatics for oncology. Cancer J 17(4):203–10PubMedCrossRef

3.

Council Directive 97/43 Euratom, on health protection of individuals against the dangers of ionizing radiation in relation to medical exposure, and repealing Directive 84/466 Euratom, 1997

4.

DIMOND. Measures for optimising radiological information and dose in digital imaging and interventional radiology. European Commission. Fifth Framework Programme. 1998–2002

5.

SENTINEL. Safety and efficacy for new techniques and imaging using new equipment to support European legislation. European Coordination Action. 2005–2007

6.

http://www.sirweb.org/about-us/IRSocietiesAroundTheWorld.shtml

7.

UNSCEAR (2000) Sources and effects of ionising radiation. United Nations Scientific Committee on the Effects of Atomic Radiation Report to the General Assembly with Scientific Annexes

8.

The 2007 recommendations of the international commission on radiological protection

9.

European Society of Radiology (2010) White paper on imaging biomarkers. Insights Imaging 1(2):42–45CrossRef

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