PET Scan

Technology—Optimizing prostate
cancer detection with PET

Leading the way for
more informed
treatment decisions
with PET

PET can detect onset of disease at the cellular level1,2

Positron emission tomography (PET) can identify changes at the cellular level and may therefore detect the early onset of disease before other imaging tests can. It enables broad, pinpoint images using radiotracers and allows for direct visualization of tumor tissue rather than the tumor’s secondary effects (osteoblastic activity or sclerosis).1,2

Consider the advantages of PET scan vs CT scan, MRI and bone scan1,3,4:

  • Enables a high detection rate that is equal to or better than MRI in the prostate bed.1
  • Can often distinguish between benign and malignant lesions when CT and MRI cannot.3
  • Allows for a higher degree of confidence with PET for detection of primary or local recurrence, nodal, osseous, and visceral disease compared with CT, MRI, or bone scan.1
  • Is not limited by size of lymph nodes with respect to detection of nodal disease. In fact, PET has been shown to have a low false-positive rate and high predictive value in enlarged non-metastatic nodes.1
  • Has a high detection-rate of metastatic disease in patients in the lower range of PSA levels.1,4
  • Can visualize bone metastases earlier compared to CT alone or bone scan.1
PET Scan Machine icon

PET can improve staging accuracy and transform disease management5,6

PET can impact decision-making in radiation therapy planning for patients with high-risk or recurrent prostate cancer by improving staging accuracy and preventing needless treatment.5,6

PET can offer more possibilities for more patients1,2,7

PET affords the opportunity for earlier intervention—so prostate cancer may be treated when it’s most amenable to therapy.1,2 Overall, it can lead to more informed treatment decisions and less over- and undertreatment of patients—bringing more hope to more people with this common and often devastating disease.7

Why PET? See the differences vs MRI, CT, and bone scan.1,8-10

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Artboard

Sensitivity=identification of disease; specificity=false positive.

Prostate-Specific Membrane Antigen Icon

Target

Optimizing imaging,
such as PET, with a
specific target for
prostate cancer: PSMA

Specific targeting of PSMA could result in improved diagnostic accuracy1,2,11-14

Suboptimal diagnostic performance can lead to less informed treatment choices and keep you from intervening when disease is most treatable.1,2

The advent of PSMA (prostate-specific membrane antigen)-targeted imaging agents can improve diagnostic accuracy in detecting prostate cancer lesions.11-13

This development shows the potential to change and improve the diagnosis and therapy of prostate cancer.1,14

PSMA is overexpressed in approximately 95% of prostate cancer, making it an ideal target13,16,17

  • PSMA is an optimal target for imaging agents in prostate cancer, as its expression is seen in approximately 95% of prostate cancer, both primary and metastatic.13,16,17
  • PSMA expression levels are increased in poorly differentiated, metastatic lesions. More importantly, they are upregulated in hormonal refractory prostate cancer.13,16 This characteristic makes PSMA crucial for early indication of disease progression in castration-resistant prostate cancer.13
  • PSMA could allow clinicians to not just reliably detect the presence of cancer but to actually understand the cancer’s aggressiveness.7,13,16
PSMA Expression icon

PSMA is readily accessible, making it ideal for diagnostic application7,13,18

On prostate cancer cells, PSMA is primarily expressed extracellularly, so it is readily accessible—a desirable feature for diagnostic application.7,13,18

PSA levels fluctuate, PSMA stays targeted1,19-22

PSMA allows for targeting of prostate cancer lesions independent of level of PSA. This is important since PSA levels can fluctuate over the course of disease progression and PSA levels can be influenced by factors like recent sexual activity, urinary tract infections, or certain medications.1,19-22

Factors that may influence PSA levels1,19-22

Exercise icon
Exercise icon
Sex icon
Sex icon
Urinary Tract Infections icon
Urinary Tract Infections icon
Certain Medications icon
Certain Medications icon
Fluorine-18 icon

Tracer

To get the most out of
PET,
an effective
radio-isotope tracer
is also required

Fluorine-18 delivers high-quality, reproducible images15

18F, or radioisotope fluorine-18, has many attributes that may help deliver high-quality, reproducible images for prostate cancer disease monitoring.15

The high spatial resolution of 18F results in clear, detailed images.15

High positron yield

+

Low positron energy

=

Enhanced image quality15

High positron yield and low positron energy means less radioactivity with the injection15,23

Image quality is enhanced by the high positron yield and low positron energy of 18F and also means less radioactivity with the injection, minimizing radiation exposure to both patients and personnel.15,23

Synthesis of 18F icon

Synthesis at regional cyclotrons allows for broad distribution15

Synthesis of 18F radiotracer at regional cyclotrons enables mass production with existing infrastructure, facilitating a broad distribution of the radiotracer to many hospitals reliably and efficiently.15

Fluorine-18 half-life enables delivery further from a cyclotron facility15

  • This, combined with a 110-minute half-life, enables delivery to diagnostics centers or hospitals that may be located further from a cyclotron facility.15
  • The half-life may also allow for delayed imaging protocols, which have been shown to increase lesion detection rate.15
US map of cyclotron facilities icon
AI systems icon

Tools

Consistent reporting
may potentially be
enhanced with AI systems19

What if you could get quantitative and consistent reporting?24

Machine learning algorithms have become more and more useful in medical imaging, particularly for analyzing digital biomarkers in positron emission tomography (PET). In oncology, artificial intelligence (AI) in PET imaging can support physicians, enabling earlier and more accurate diagnosis as well as personalized treatment plans.24

Image reading assisted by AI systems19

Enables automated quantification of images19
AI systems are being developed to provide quantitative and consistent reporting. AI systems may have the potential to improve management of prostate cancer patients by enabling the automated quantification of images, which can be tedious and time-consuming for even the most expert and skilled radiologists.19

More scans in a shorter period of time19

By increasing the rate at which images can be processed, physicians can review more scans in a shorter amount of time.19

Scan Results
Scan Results

May standardize image reporting19

Equally as important, AI systems may help standardize image interpretation and reporting to the referring physician, saving both time and effort.19

Potential to standardize image reporting19

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Group 11

May facilitate a more consistent approach19

By potentially increasing the reproducibility of image reporting, AI systems may support a more consistent approach to the management of prostate cancer patients.19

The value of PSMA PET is
directly linked to the quality of reporting19,25

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14. Zippel C, Ronski SC, Bohnet-Joschko S, et al. Current status of PSMA-radiotracers for prostate cancer: data analysis of prospective trials listed on clinicaltrials.gov. Pharmaceuticals. 2020;1-13. doi:10.3390/ph13010012
15. Werner RA, Derlin T, Lapa C, et al. 18F-labeled, PSMA-targeted radiotracers: leveraging the advantages of radiofluorination for prostate cancer molecular imaging. Theranostics. 2020;10(1):1‐16.
16. Hupe MC, Philippi C, Roth D, et al. Expression of Prostate-Specific Membrane Antigen (PSMA) on biopsies is an independent risk stratifier of prostate cancer patients at time of initial diagnosis. Front Oncol. 2018;8:623. doi:10.3389/fonc.2018.00623
17. Queisser A, Hagedorn SA, Braun M, Vogel W, Duensing S, Perner S. Comparison of different prostatic markers in lymph node and distant metastases of prostate cancer. Mod Pathol. 2015;28(1):138‐145. doi: 10.1038/modpathol.2014.77
18. Stallard J. PSMA: A new target for prostate cancer treatment. Memorial Sloan Kettering Cancer Center. Updated November 15, 2017. Accessed May 12, 2020. https://www.mskcc.org/blog/psma-new-target-prostate-cancer-treatment
19. Data on file. Progenics Pharmaceuticals, Inc.
20. Oh SW, Cheon GJ. Prostate-specific membrane antigen PET imaging in prostate cancer: opportunities and challenges. Korean J Radiol. 2018;19(5):819‐831. doi: 10.3348/kjr.2018.19.5.819
21. Prostate Specific Antigen (PSA) Test. Cancer Research UK. Updated August 9, 2019. Accessed May 12, 2020. https://www.cancerresearchuk.org/about-cancer/prostate-cancer/getting-diagnosed/tests/prostate-specific-antigen-psa-test
22. Screening Tests for Prostate Cancer. American Cancer Society. Updated August 1, 2019. Accessed June 4, 2020. https://www.cancer.org/cancer/prostate-cancer/detection-diagnosis-staging/tests.html
23. Werner RA, Chen X, Rowe SP, Lapa C, Javadi MS, Higuchi T. Moving Into the Next Era of PET Myocardial Perfusion Imaging: Introduction of Novel 18F-labeled Tracers. Int J Cardiovasc Imaging. 2019;35(3):569-577.
24. Duffy, IR, Boyle, AJ, Vasdev, N. Improving PET imaging acquisition and analysis with machine learning: a narrative review with focus on alzheimer’s disease and oncology. Molecular Imaging. 2019;18:1-11. doi:10.1177/1536012119869070
25. Hope, TA, Goodman JZ, Allen, IE, et al. Metaanalysis of 68Ga-PSMA-11 PET accuracy for the detection of prostate cancer validated by histopathology. J Nucl Med. 2019;60(6);2019.