[11C] acetoacetate utilization by breast and prostate tumors: a PET and biodistribution study in mice.
OBJECTIVE
A significant positive correlation has been observed between ketone body availability and their uptake by tumor cells. Our objective was to evaluate [11C]acetoacetate as a potential tracer of ketone body utilization by breast and prostate tumors and to compare it with [11C]acetate.


METHODS
Biodistribution studies were performed with [11C]acetoacetate and [11C]acetate in mice bearing breast or prostate tumors. The percentage of the injected dose accumulated per gram of tissue was determined. These results were complemented by dynamic positron emission tomography (PET) imaging of the radiotracer uptake and dosimetry calculations.


RESULTS
[11C]Acetoacetate uptake was optimal between 5 and 30 min, with maximal uptake of 2.72, 2.42, 2.54, and 2.19% injected dose (%ID)/g for MC7-L1, MC4-L2, PC3, and LN-CaP tumors respectively. Tumor retention for [11C]acetoacetate tended to be higher than [11C]acetate, but this did not reach statistical significance. [11C]Acetate uptake was reached within 15 min with optimal uptake of 1.25, 2.30, and 0.96%ID/g for MC7-L1, MC4-L2, and PC-3 tumors, respectively.


CONCLUSIONS
We observed a moderate uptake of [11C]acetoacetate in breast and prostate tumors with low background activity due to rapid elimination of this tracer. Further studies are warranted to determine if this tracer can detect slow-growing breast and prostate cancers in the clinical setting.
Authier
Simon
S
Sherbrooke Molecular Imaging Center, Faculty of Medicine and Health Sciences, Université de Sherbrooke, 3001, 12th Avenue N., Sherbrooke, QC, Canada, J1H 5N4. Simon.Authier@Usherbrooke.ca
Tremblay
Sébastien
S
Dumulon
Véronique
V
Dubuc
Céléna
C
Ouellet
René
R
Lecomte
Roger
R
Cunnane
Stephen C
SC
Bénard
François
F
D000090:Acetoacetates / Q000493:pharmacokinetics*; D000818:Animals; D002250:Carbon Radioisotopes; D045744:Cell Line, Tumor; D005260:Female; D006801:Humans; D008297:Male; D015674:Mammary Neoplasms, Animal / Q000000981:diagnostic imaging* / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D049268:Positron-Emission Tomography / Q000379:methods*; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism* / Q000473:pathology; D014018:Tissue Distribution; D023041:Xenograft Model Antitumor Assays
D000090:Acetoacetates; D002250:Carbon Radioisotopes; C016635:acetoacetic acid