Ga68 Imaging. Roland HUSTINX Division of Nuclear Medicine and Oncologic Imaging Centre Hospitalier Universitaire de Liège Belgium

Transcription

1 Ga68 Imaging Roland HUSTINX Division of Nuclear Medicine and Oncologic Imaging Centre Hospitalier Universitaire de Liège Belgium

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3 68 Ga Produced by a 68 Ge/ 68 Ga generator Decays by positron emission in 89% yield Emax of the positron 1.9 MeV 18 F: 0.63 MeV T1/2 68 minutes

4 68 Ge/ 68 Ga Generators Ge T1/2 271 days Decays into a 100% electron capture mode at 106 kev in 68 Ga. [ nat Ga(p,xn) 68 Ge] or [ 69 Ga(p,n) 68 Ge] reactions in the nominal energy range MeV (ideally 28 MeV) A MeV cyclotron at 250μA can produce about 500 mci 68 Ge after 4-5 days irradiation eight 50 mci-generators per batch (500+ generators a year). Issues: Availability of 68 Ge / cost Sterility 68 Ge breakthrough 68 Ga can also be produced with an 18 MeV cyclotron

5 68Ge/68Ga Generators: «chemicals Vs pharmaceuticals» 4 manufacturers Berlin, Germany Cape Town, South Africa Munich, Germany Fleurus, Belgium

6 Radiopharmacy

7 Somatostatin Receptors Imaging Johnbeck et al. Future Oncol. (2014) 10(14),

8 Comparison with Octreoscan Higher sensitivity More convenient for the patient Faster results Lower radiation burden Less expensive Buchmann et al. Eur J Nucl Med Mol Imaging (2007) 34: Krausz et al. Mol Imaging Biol (2011) 13:

9 Carcinoid 111 In-Octreoscan 68 Ga-DOTANOC

10 Biodistribution & Dosimetry Sandstrom et al. J Nucl Med 2013; 54: Velikyan et al J Nucl Med. 2014;55:

11 Clinical performances: TATE vs TOC

12 Wild et al. J Nucl Med. 2013;54:

13 Pancreatic NET, grade 1, Ki67 <1% 68 Ga-DOTANOC FDG

14 Gastrinoma, surgery, increased chromogranin: relapse? FDG 68 Ga-DOTANOC

15 Medullary Thyroid Carcinoma 68 Ga-DOTANOC

16 Relapse of MTC: TP for LN & bone met, FN for liver mets

17 Pitfall: insulinoma

18 DOTATATE & DOTANOC, 1 year apart NET, treated by SS analogue 68 Ga-DOTATATE 68 Ga-DOTANOC

19 68 Ga-DOTANOC 68 Ga-DOTATATE

20 Midgut NET, liver & LN mets, treated by SS analogue DOTATATE & DOTANOC 8 months apart 68 Ga-DOTANOC 68 Ga-DOTATATE

21 Pitfall: radiation therapy 4 years before

22 «68 Ga-DOTATOC PET/CT was considerably cheaper than 111 In-DTPA-octreotide with respect to both material and personnel costs. Furthermore, by using 68 Ga-DOTATOC PET/CT considerably fewer additional examinations were needed reducing the consequential costs significantly.»

23 68GA-DOTA-XXX: Quantitative imaging and dosimetry for individualized treatment Velikyan et al. J Nucl Med 2014; 55:

24 79%

25 Graf et al. Int J Radiation Oncol Biol Phys, Vol. 85, No. 1, pp , 2013

26 Glu-CO-Lys(Ahx)-[68Ga(HBED-CC)] 68 Ga-PSMA-HBED-CC 68 Ga-PSMA-11 «68 Ga-PSMA» PSMA: type II transmembrane glycoprotein Low expression by prostate cells Hyperxpression by prostate adenocarcinoma Exact function not known

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28 Sensitivity Vs PSA level Perera et al. EUROPEAN UROLOGY 70 (2016)

29 Biochemical relapse: comparison with Choline Lesions Patients Schwenk et al Eur J Nucl Med Mol Imaging (2017) 44:92 101

30 Diagnostic accuracy Perera et al. EUROPEAN UROLOGY 70 (2016)

31 PSA 0.88 ng/ml Doubling time 12 Mo (bladder ca)

32 PSA 0.7 ng/ml

33 PSA 1.61 ng/ml: local recurrence + bone met

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35 Specificity? «However, since 68Ga-PSMA-11-PET/CT was introduced, the results prove the excellent specificity of this compound indicating that any uptake of 68Ga-PSMA-11 above local background in CT- or MR morphological visible lesions of PCa-patients should be regarded as highly suspicious for PCa» (Afshar-Oromieh et al, J Nucl Med Jan 6.) False positive results: Other cancers: lymphomas, follicular thyroid ca, sarcoma, rectal ca, HCC, NET, RCC, etc. Benign tumors: thyroid adenoma, schwannoma, meningioma, etc. Benign lesions: fractures, Paget s, stroke, sarcoidosis, anthracosis, etc. Normal variants: cervicothoracic (stellate) & coeliac LN

36 Lung adenocarcinoma Pancreatic adenocarcinoma: PSMA & FDG

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38 Theranostics

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40 PET/CT V/Q scanning? Galligas: 50 MBq 68 Ga in a Technegas generator - 10 MBq are inhaled 68 Ga-MAA : 50 MBq I.V. Activity ratios V/Q: 1/4 ldct followed by 2 PET acquisitions of 6-9 min. each

41 99m Tc ventilation SPECT 99m Tc-MAA perfusion SPECT 68 Ga ventilation PET 68 Ga-MAA perfusion PET Hofman et al. J Nucl Med. 2011;52:

42 68 Ga-EDTA PET/CT Imaging and Plasma Clearance for Glomerular Filtration Rate Quantification Hofman M et al. J Nucl Med 2015; 56:

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44 68 Ga, ready to take off?

45 Conclusions 68 Ga: Highly attractive combination Physical and chemical properties Cost/availability Already a clinical difference maker (SSRI & prostate cancer) Regulatory issues to be solved Small batches (few patients)