Tumor imaging in patients with advanced tumors using a new (99m) Tc-radiolabeled vitamin B12 derivative.

Details

Serval ID
serval:BIB_F5FB4407E95B
Type
Article: article from journal or magazin.
Collection
Publications
Title
Tumor imaging in patients with advanced tumors using a new (99m) Tc-radiolabeled vitamin B12 derivative.
Journal
Journal of Nuclear Medicine : Official Publication, Society of Nuclear Medicine
Author(s)
Sah B.R., Schibli R., Waibel R., von Boehmer L., Bläuenstein P., Nexo E., Johayem A., Fischer E., Müller E., Soyka J.D., Knuth A.K., Haerle S.K., Schubiger P.A., Schaefer N.G., Burger I.A.
ISSN
1535-5667 (Electronic)
ISSN-L
0161-5505
Publication state
Published
Issued date
2014
Volume
55
Number
1
Pages
43-49
Language
english
Notes
Publication types: Journal Article Publication Status: ppublish
Abstract
Targeting cancer cells with vitamin B12 (cobalamin) is hampered by unwanted physiologic tissue uptake mediated by transcobalamin. Adhering to good manufacturing practice, we have developed a new (99m)Tc-cobalamin derivative ((99m)Tc(CO)3-[(4-amido-butyl)-pyridin-2-yl-methyl-amino-acetato] cobalamin, (99m)Tc-PAMA-cobalamin). The derivative shows no binding to transcobalamin but is recognized by haptocorrin, a protein present in the circulation and notably expressed in many tumor cells. In this prospective study, we investigated cancer-specific uptake of (99m)Tc-PAMA-cobalamin in 10 patients with various metastatic tumors.
METHODS: Ten patients with biopsy-proven metastatic cancer were included. Dynamic imaging was started immediately after injection of 300-500 MBq of (99m)Tc-PAMA-cobalamin, and whole-body scintigrams were obtained at 10, 30, 60, 120, and 240 min and after 24 h. The relative tumor activity using SPECT/CT over the tumor region after 4 h was measured in comparison to disease-free lung parenchyma. Patients 3-10 received between 20 and 1,000 μg of cobalamin intravenously before injection of (99m)Tc-PAMA-cobalamin. The study population comprised 4 patients with adenocarcinomas of the lung, 3 with squamous cell carcinomas of the hypopharyngeal region, 1 with prostate adenocarcinoma, 1 with breast, and 1 with colon adenocarcinoma.
RESULTS: The median age of the study group was 61 ± 11 y. Six of 10 patients showed positive tumor uptake on (99m)Tc-PAMA-cobalamin whole-body scintigraphy. The scan was positive in 1 patient with colon adenocarcinoma, in 3 of 4 lung adenocarcinomas, in 1 of 3 hypopharyngeal squamous cell carcinomas, and in 1 breast adenocarcinoma. Renal uptake was between 1% and 3% for the left kidney. Predosing with cobalamin increased the tumor uptake and improved blood-pool clearance. The best image quality was achieved with a predose of 20-100 ug of cold cobalamin. The mean patient dose was 2.7 ± 0.9 mSv/patient.
CONCLUSION: To our knowledge, we report for the first time on (99m)Tc-PAMA-cobalamin imaging in patients with metastatic cancer disease and show that tumor targeting is feasible.
Keywords
Aged, Aged, 80 and over, Biopsy, Female, Humans, Male, Middle Aged, Multimodal Imaging, Neoplasm Metastasis, Neoplasms/radionuclide imaging, Organotechnetium Compounds/pharmacology, Prospective Studies, Radionuclide Imaging, Radiopharmaceuticals/pharmacology, Sensitivity and Specificity, Technetium/pharmacology, Time Factors, Tissue Distribution, Tomography, Emission-Computed, Single-Photon, Tomography, X-Ray Computed, Vitamin B 12/analogs & derivatives, Vitamin B 12/chemistry, Whole Body Imaging
Pubmed
Open Access
Yes
Create date
17/06/2015 16:00
Last modification date
21/08/2019 6:36
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