J Nucl Med. 2007; 48 (Supplement 2):386P
Oncology: Clinical Diagnosis-Solid Tumors
Clinical Diagnosis-Solid Tumors Posters |
Comparison of C-11 methionine and FDG PET in detection and evaluation of ovarian tumor
Kyosan Yoshikawa1,
Naotake Tanaka2,
Mitsuhiko Hasebe1,
Sherif Abd-Elrazek1,
Hiroyuki Ishikawa1,
Kenji Sagou1,
Katsumi Tamura1,
Katsuyuki Tanimoto1,
Susumu Kandatsu1,
Tsuneo Saga1,
Kazutoshi Suzuki1 and
Hirohiko Tsujii1
1 National Institute of Radiological Sciences, Chiba-shi, Japan; ;
2 Chiba Cancer Center, Nitona-cho, Chuo-ku, Chiba, Japan
1640
Objectives: FDG and C-11 methionine (MET) are commonly used tumor-seeking agents. This study compared FDG and MET in detecting and evaluating ovarian tumors in the same patients. Methods: Eighteen patients with ovarian lesions were studied with PET using MET as well as FDG. There were eleven patients with clinically suspected recurrent ovarian cancer, four patients with primary ovarian cancer and three patients with benign ovarian tumors before surgical operation. Both MET and FDG PET were performed within one week for each patient. PET images were obtained by ECAT EXACT HR+ or ECAT EXACT 47 (CTI/Siemens, Inc., Knoxville, TN). Standardized up take values (SUVs) on FDG images and tumor-to-muscle ratios (TMRs) on MET images were produced. MRI and/or CT imaging were also done. A tumor marker, CA125, was checked for each patient. Results: There was statistically significant difference in mean SUV and in mean TMR between ovarian cancer and benign tumor (p=0.003 and p=0.001). The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of FDG-PET were 92.9%, 75%, 92.9%, 75% and 88.9% respectively. Foregoing indexes of MET-PET were exactly the same as FDG-PET, 92.9%, 75%, 92.9%, 75% and 88.9%. Indexes of CT/MRI were 64.3%, 75%, 90%, 37.5% and 66.7%. Indexes of CA125 were 71.4%, 25%, 76.9%, 20% and 61.1%, respectively. MET was not able to evaluate liver lesions under the influence of massive physiological accumulation in liver tissue, but a patient showed fine MET uptake at a metastatic lymph node of retroperitoneal area without FDG uptake. Conclusions: PET using FDG and MET appear equally effective in detecting ovarian tumors. Diagnostic accuracy of FDG and MET PET were superior to conventional imaging modalities such as CT/MRI.
