In research undertaken in Japan by Dr. Nobuyuki Oyama, MD, PhD, 18 patients with prostate cancer confirmed by biopsy underwent positron emission tomography (PET) scanning using two different radiotracers: 18F-FDG and 11C-acetate. Of those, 100% of 11C-acetate PET scans were positive for primary prostate cancer, while only 83% of 18F-FDG PET scans were positive. 11C-Acetate not only showed significantly greater sensitivity for prostate cancer, it was also better able to detect distant metastases. The researchers concluded that 11C-acetate PET imaging may be able to detect prostate cancers that are currently undetectable by 18F-FDG PET.
PET scans using various tracer elements have been increasingly recognized as a vital tool in the diagnosis of many cancers, including melanoma, lymphoma, and lung, colorectal, and breast cancer. Patients undergoing PET scans are injected with the tracer element, which is then taken up by the body tissues. Areas of higher metabolic activity, such as cancer cells, tend to absorb more of the tracer element, enabling physicians to distinguish between normal and cancerous cells. Thus PET can often detect a tumor before it becomes visible by conventional CT or MRI, which primarily image anatomical changes. PET can also be used to evaluate whether a treatment is working.
Unfortunately, 18F-FDG PET has not proven effective in detecting early prostate cancer. This is because the 18F-FDG (fluorodeoxyglucose) tracer is not taken up well by prostate tumors, which often have a slower glucose metabolism. 11C-Acetate also responds to metabolic activity, but how or why it has higher uptake within prostate tumors is not completely clear.
11-C-Acetate PET Imaging of Prostate Cancer was written by Nobuyuki Oyama, MD, PhD, Hironobu Akino, MD, PhD, Hiroshi Kanamaru, MD, PhD, Yuji Suzuki, MD, PhD, Satoshi all of the Department of Urology, Fukui Medical University, Fukui, Japan, Satoshi Muramoto, MD, Department of Radiology, Fukui Medical University, Yoshiharu Yonekura, MD, PhD, Biomedical Imaging Research Center, Fukui Medical University, Norihiro Sadato, MD, PhD, National Institute for Physiological Sciences, Okazaki, Japan, Kazutaka Yamamoto, MD PhD, Wakasa Energy Research Center, Fukui, Japan and Kenichiro Okada, MD PhD, Department of Urology, Fukui Medical University, Fukui, Japan.
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