RT Journal Article
SR Electronic
T1 Clinical evaluation of the sigma-2 receptor radiotracer [18F]ISO-1 in lymphoma, breast and head & neck cancer patients
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 4
OP 4
VO 53
IS supplement 1
A1 Dehdashti, Farrokh
A1 Laforest, Richard
A1 Shoghi, Kooresh
A1 Tu, Zhude
A1 Aft, R.
A1 Nussembaum, B.
A1 Bartlett, Nancy
A1 Gao, F.
A1 Kreisel, F.
A1 Mach, Robert
YR 2012
UL http://jnm.snmjournals.org/content/53/supplement_1/4.abstract
AB 4 Objectives The sigma-2 PET ligand [18F]ISO-1 has shown promise in preclinical imaging studies in animal models of cancer. The goal of the current study was to determine the correlation between tumor uptake of [18F]ISO-1 and histological measures of cell proliferation in cancer patients. Methods PET imaging studies were conducted on a CTI/Siemens Biograph-40 PET/CT scanner in patients with breast cancer (N = 13), head & neck (H&N) cancer (N = 10) and lymphoma (N = 7). Patients were injected with ~8 mCi (296 MBq) of [18F]ISO-1. PET images were evaluated using maximum standardized uptake value (SUVmax), tumor: muscle (T/M) ratio, and Logan graphical analysis. The degree of uptake of [18F]ISO-1 was compared with histological measures of cell proliferation (Ki-67 and mitotic index) in 28 of the 30 patients studied. All patients underwent vital signs measurements, clinical laboratory testing and electrocardiography before [18F]ISO-1 administration, as well as during and after completion of imaging. Results There was a high variability in uptake of [18F]ISO-1 in tumors, as expected with a radiotracer that measures the proliferative status of solid tumors. [18F]ISO-1 uptake was observed in the primary tumors; lymph node involvement was observed in lymphoma. In addition, [18F]ISO-1 uptake in lymph node and bone marrow was noted in metastatic disease. The best correlation between [18F]ISO-1 uptake and histological measures of cell proliferation was observed when comparing the T/M ratio at 1 hr post-injection of the tracer with the Ki-67 labeling index (p = 0.011). The patients could be stratified into groups of low (Ki-67 < 0.45; T/M = 3.06 ± 1.17) versus high proliferative status (Ki-67 > 0.45; T/M = 5.35 ± 3.59; p = 0.02). No adverse effects of [18F]ISO-1 were encountered. Conclusions Our results suggest that [18F]ISO-1 is a promising radiotracer for imaging the proliferative status of solid tumors. Expanded studies with this radiotracer in cancer patients are clearly warranted. Research Support Funded by Isotrace Technologies, Inc