Molecular Imaging and Radionuclide Therapy最新文献

Objectives: The pharmacological stress test with vasodilator agents is an alternative cardiological diagnostic tool for patients with contraindications to the classical stress test provided by physical activity during single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI). The study compared the frequency of the side effects of regadenoson and dipyridamole during a SPECT MPI.

Methods: This retrospective study included data of 283 consecutive patients who underwent pharmacological stress tests in years 2015-2020. The study group consisted of 240 patients who had received dipyridamole and 43 patients who had received regadenoson. The collected data included the patients' characteristics, the occurrence of side effects (divided into mild: headache, vertigo, nausea, vomiting, dyspnea, chest discomfort, hot flushes, general weakness and severe: bradycardia, hypotension, loss of consciousness), and blood pressure values/measurements.

Results: Overall, complications occurred relatively often (regadenoson: 23.2%, dipirydamol: 26.7%, p=0.639). Procedure discontinuation was necessary in 0.7% of examinations, whereas pharmacological support was necessary in 4.7%. There was no difference in the prevalence of mild (regadenoson: 16.2%, dipirydamol: 18.3%, p=0.747) and severe complications (regadenoson: 11.6%, dipyridamole: 15.0%, p=0.563). However, regadenoson has been found to cause a significantly smaller mean decrease of systolic blood pressure (SBP) (regadenoson: -2.6±10.0 mmHg, dipyridamole: -8.7±9.6 mmHg, p=0.002), diastolic blood pressure (DBP) (regadenoson: -0.9±5.4 mmHg, dipyridamole: -3.6±6.2 mmHg, p=0.032), as well as mean arterial pressure (MAP) (regadenoson: -1.5±5.6 mmHg, dipyridamole: -5.4±6.5 mmHg, p=0.001).

Conclusion: Regadenoson and dipyridamole presented a similar safety profile during SPECT MPI. However, regadenoson has been found to cause significantly smaller decreases in SBP, DBP, and MAP.

Objectives: This study was conducted to detect atherosclerotic plaques with somatostatin receptor scintigraphy (SRS) using Tc-99m-octreotide that binds to somatostatin receptor-2.

Methods: Of the 783 patients referred for myocardial perfusion imaging (MPI), 52 underwent additional chest single-photon emission computed tomography (SPECT) with Tc-99m-octreotide and participated in this study. In addition, 43 patients who underwent Tc-99m-octreotide scan for neuroendocrine tumor (NET) also received cardiac SPECT. Angiography was performed within 1 month after SRS for 19 patients who showed intensive uptake in SRS and had cardiac risk factors.

Results: Of 52 patients who underwent MPI and SRS, 15 showed intensive cardiac uptake in SRS. Moreover, of 43 patients who were referred for NET, 4 patients had marked cardiac uptake in SRS in the heart. Nineteen patients including 12 women and 7 men aged 28 to 84 (58±8.04) years underwent coronary angiography. SRS and angiography in the left anterior descending territory were concordant in 15/19 (79%) patients, whereas only 7/15 (46%) cases had concordant MPI and angiography results. In the right coronary artery territory, SRS and angiography were concordant in 16/19 (84%) cases, while MPI and angiography were concordant in 11/15 (73%) cases. In the left circumflex artery territory, SRS and angiography were concordant in 15/19 (79%) cases, whereas MPI and angiography were concordant in 6/15 (40%) cases. In the remaining 76 patients who did not undergo coronary angiography based on cardiovascular profile and SRS, no cardiac events occurred in a follow-up of 2-11 months (7.52±2.71).

Conclusion: Tc-99m-octreotide uptake was more concordant with coronary plaques relative to MPI findings, suggesting a potential role for Tc-99m-octreotide in the evaluation of atherosclerosis.

Objectives: This prospective study was planned to compare the predictive value of dynamic ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in locally advanced breast cancer patients (LABC) receiving neoadjuvant chemotherapy (NAC).

Methods: Twenty seven patients with LABC [median age: 47, (26-66)] underwent a dynamic ¹⁸F-FDG PET study at baseline, and after 2-3 cycles of (NAC) were included (interim). Maximum standardized uptake value (SUV_max) values and SUV ratios for the 2^nd, 5^th, 10^th, and 30^th minutes and dynamic curve slope (SL) values and SL ratios were measured using ¹⁸F-FDG dynamic data. In addition, the values of SUV_mean (2minSUVmean), SULpeak (2minSULpeak), metabolic volume (2minVol), and total lesion glycolysis (2minTLG) were measured for the first 2 min. Percent changes between baseline and interim studies were calculated and compared with the pathological results as the pathological complete response (PCR) or the pathological non-complete response (non-PCR). Receiver operating characteristic curves were obtained to calculate the area under the curve to predict PCR. Optimal threshold values were calculated to discriminate between PCR and non-PCR groups.

Results: Baseline study SUV 30 (p=0.044), SUV 30/2 (p=0.041), SUV 30/5 (p=0.049), SUV 30/10 (p=0.021), SL 30/2 (p=0.029) and SL 30/5 (p=0.027) values were statistically significant different between PCR and non-PCR groups. The percentage changes of 2minVol between PCR and non-PCR groups were statistically significant. For the threshold value of -67.6% change in 2minVol, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 87.2%, 77.8%, 63.6%, 93.3%, and 80.7%, respectively (area under the curve: 0.826, p=0.009).

Conclusion: Semiquantitative parameters for dynamic ¹⁸F-FDG PET can predict PCR. % changes in 2minVol can identify non-responding patients better than other parameters.

Objectives: Detection of a sentinel lymph node (SLN) in patients with endometrial cancer (EC) reduces the rate of unnecessary systemic lymph dissection. The aim of this study was to assess the SLN detection rate, accuracy of the method using Tc-99m-SENTI-SCINT and the rate of metastatic nodal involvement in patients with preoperative first stage EC.

Methods: A prospective study of SLN biopsy of 41 patients with stage I EC was conducted after cervical application of 4mCi Tc-99m-SENTI-SCINT. Planar lymphoscintigraphy and single-photon emission computed tomography/computed tomography (SPECT/CT) of the pelvis were performed, followed by site-specific lymphadenectomy in intermediate-risk patients if no SLN was detected per hemipelvis and pelvic lymphadenectomy in all high-risk patients.

Results: Pre-operative detection rate of planar lymphoscintigraphy was 80.49 [95% confidence interval (CI): 68.36-92.62] and of SPECT/CT 95.12 (95% CI: 88.52-101.7). The total intraoperative SLN detection rate was 95.12 (95% CI: 88.52-101.7) per patient and 26.83 (95% CI: 19.91-33.75) bilaterally. The average number of SLNs removed was 1.6±0.8. The most common anatomical location of SLN was the right external iliac region. The SLN metastatic rate was 17%. Both sensitivity and negative predictive value regarding metastatic involvement were 100%.

Conclusion: The SLN detection rate, sensitivity and negative predictive value using Tc-99m-SENTI-SCINT in patients with EC in our study were high. The application of ultra-staging in the histopathological analysis of SLN increases the detection of nodal metastases and improves the staging in these patients.

Ovarian cancer is one of the deadliest tumors among women. It mostly metastasizes to the liver, pleura, lungs, and bones. We present a sixty-six-year-old patient with skin lesions. The patient who underwent biopsy due to skin lesions was diagnosed with ovarian cancer. ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/magnetic resonance imaging (PET/MRI) performed for metastasis search shows widespread skin involvement, especially in the lower abdomen and legs. Skin involvement it ovarian cancer can be rarely seen, and in this article we would like to share ¹⁸F-FDG PET/MRI of skin involvement in ovarian cancer.

In differentiated thyroid cancer, radioiodine therapy and whole body scans (WBS) are integral part of disease management. We present the case of a 33-year-old woman with multifocal thyroid carcinoma who was treated with radioiodine. Post-treatment WBS scintigraphy showed focal increased I-131 uptake in the spleen, although stimulated thyroglobulin level was not suggestive of distant metastasis. Dynamic magnetic resonance imaging performed later revealed that the finding was an incidental splenic cyst. Radioiodine uptake is not specific to the thyroid tissue. Benign pathologies showing increased radioiodine uptake should be considered in cases with splenic radioiodine accumulation in WBSs.

Meningiomas constitute 37% of primary central nervous system tumors and are more common in women. Also may occur with other primary malignancies, which can cause confusion with the metastasis in whole body bone scan (WBBS) imaging. A 58-year-old woman diagnosed with breast cancer was referred to the WBBS for the investigation of possible bone metastases. In the planar images, radiotracer uptake at multiple sites was detected on the anterior side of the skull base and the posterior side of the vertex of the cranium. Single photon emission computed tomography/computed tomography was performed for anatomical localization of possible metastatic lesions, and it revealed that detected accumulations of radiotracer did not belong to the bone metastases; uptakes were located at the cerebral parenchyma and the lesions in the falx cerebri. Patient history explained that she had been diagnosed with meningioma five years ago, which mimicked bone metastases in this study.

Objectives: We aimed to investigate and compare the role of computed tomography (CT)-based attenuation-corrected images (AC) with non-attenuation-corrected images (NAC) obtained by single-photon emission computed tomography/computed tomography (SPECT/CT) myocardial perfusion imaging (MPI).

Methods: The data of 124 patients who were applied one-day stress-rest Tc-99m sestamibi SPECT/CT MPI and who had coronary angiography (CAG) results within ±3 months were retrospectively reviewed. AC and NAC images were visually evaluated by two nuclear medicine specialists in a consensus. CAG results were used as the reference standard.

Results: Specificity, sensitivity, and accuracy were calculated as 66%, 61%, 71%, 79% and 69%, 70% for AC and NAC imaging in the whole group, respectively. There was no statistically significant difference between AC and NAC images for specificity, sensitivity, and accuracy in the male and female subgroups. In the diagnosis of right coronary artery (RCA) disease, CT AC significantly increased the specificity from 87% to 96%. However, in the left anterior descending artery (LAD) region, the specificity was significantly reduced from 95% to 77%.

Conclusion: CT-based AC did not significantly contribute to diagnostic performance for increased specificity for the RCA and reduced specificity in the LAD region. Therefore, AC images should always be evaluated side by side with NAC images to benefit from the different advantages of both techniques.