Utility of ^99mTc-PEG₄-E[PEG₄-c(RGDfK)]₂ in Posttherapy Surveillance of Patients with Reelevated Carcinoembryonic Antigen Levels

Abstract

ObjectivesTo evaluate the efficacy of 99mTc-PEG4-E[PEG4-c (RGDfK)]2 (99mTc-3PRGD2) single photon emission computed tomography (SPECT) in monitoring the recurrence of malignancies.Materials and Methods99mTc-3PRGD2 SPECT was performed on 28 patients (10 females and 18 males; median age 49.2 years) suspected of recurrent malignancies due to an asymptomatically reelevated carcinoembryonic antigen level. The SPECT was performed 0.5 h after an intravenous injection of 11.1 MBq/kg (0.3 mCi/kg) of 99mTc-3PRGD2. The SPECT and concurrent contrast-enhanced computed tomography (ceCT) findings were analyzed with reference to the histopathological findings and/or clinical follow-up data.ResultsRecurrences were identified in 20 out of the 28 patients (prevalence 71.4s%) with altogether 26 lesions. Fifteen lesions were confirmed by histopathological findings, and the other 11 lesions were confirmed by serial radiological or clinical follow-up. Of the 20 patients with recurrent malignancies, 12 (60s%) were correctly identified by 99mTc-3PRGD2 SPECT. In the patient-based analysis, the sensitivity and specificity of 99mTc-3PRGD2 SPECT were 60 and 100s%, respectively, and the positive and negative predictive values were 100 and 50s%, respectively. In the lesion-based evaluation, the sensitivity and specificity were 62 and 100s%, respectively. The sensitivity and specificity of the ceCT in the patient-based evaluation were 60 and 75s%, respectively, and the positive and negative predictive values were 86 and 40s%, respectively. In the lesion-based evaluation, the sensitivity and specificity of the ceCT were 70 and 84s%, respectively.Conclusions99mTc-3PRGD2, as a new SPECT tracer targeting the integrin αvβ3 receptor, was more useful in distinguishing recurrences as compared to ceCT.

Effect of Electroacupuncture on 99mTc-Sodium Pertechnetate Uptake and Extracellular Fluid Free Molecules in the Stomach in Acupoint ST36 and ST39

“…Na 99m TcO4 SPECT/CT images were read and interpreted by the consensus of three experienced nuclear medicine physicians with reference to SPECT/CT fusion images. For semiquantitative analysis, gastric-to-background ratios of SPECT images were measured and calculated by the same person using a consistent standard 14 . The data are collected and compared with before EA, during EA, and after EA, to observe the adjusting effect of EA on gastric function.…”

Clinical Value of 99mTc-3PRGD2 SPECT/CT in Differentiated Thyroid Carcinoma with Negative 131I Whole-Body Scan and Elevated Thyroglobulin Level

“…Synthesis of the labeling precursor, kit preparation and subsequent 99m Tc-labeling were performed as previously described 36 . 99m Tc-3PRGD2 SPECT/CT and planar imaging were performed 5–54 months (median 15.31 months) after the last radioiodine ablation.…”

“…The patients were followed up for 6–30 months (median 17.5 months) after the 99m Tc-3PRGD2 SPECT/CT imaging was performed. The SPECT/CT findings were compared with histopathological findings, serial radiological or clinical follow-up 23 , 36 . Patients were regarded as recurrence positive if either (1) histopathological examination by either biopsy or reoperation showed recurrence, (2) posttreatment WBS after empirical 131 I therapy was compatible with recurrence or distant metastasis, (3) sTg levels showed consistently elevated levels at follow-up, whether 131 I treatment was performed or not, (4) other imaging modalities displayed recurrent disease at follow-up, or (5) sTg levels dropped following empirical 131 I therapy (non-stimulated Tg < 2 ng/mL, or TSH-stimulated Tg values < 10 ng/mL for more than 6 months).…”

Hyperplastic thymus with increased angiogenesis is correlated with elevated serum thyroglobulin level in differentiated thyroid cancer patients with TENIS syndrome

“…A volume-of-interest method was used to obtain the maximum values of the enlarged thymus in mediastinal region. The blood pool of the aortic arch was set as control [ 43 ].…”

“…The SPECT/CT findings were compared with histopathological findings, serial radiological or clinical follow-up [ 43 ]. In patients with only stable thymus enlargement on concomitant imaging, no therapeutic intervention was initiated, whereas patients with other metastatic lesions received surgery and/or an empirical 131 I treatment.…”