Nuklearmedizin-nuclear Medicine最新文献

Purpose: To compare bone marrow biopsy (BMB) with [18F]-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (PET/CT) imaging in the demonstration of bone marrow involvement in children with Hodgkin's Lymphoma (HL) and to investigate the effectiveness of PET/CT imaging and thus the necessity for BMB at staging.

Methods: Pediatric patients with HL, who underwent both bilateral iliac BMB and PET/CT imaging at disease staging were retrospectively analyzed. In determining bone marrow involvement (BMinv), BMB and/or first/follow-up PET/CT imaging were eligible for review.

Results: Fifty-six patients were included. BMinv was detected by PET/CT imaging in 6/56 (10.7%), whereas the proportion was 3/56 (5.3%) in BMB specimens. Bone marrow biopsies and PET/CT images were concordant in 53/56 (94.6%) patients with BMB specimens missing three cases of BMinv detected by PET/CT. When diagnostic accuracy was calculated, sensitivity, specificity, positive predictive value and negative predictive values for PET/CT were 100%, 100%, 100%, 100%, respectively, and the same values for BMB were 50%, 100%, 100%, 94.3%, respectively.

Conclusions: The results of PET/CT and BMB for staging of pediatric HL patients were compatible, and PET/CT imaging was found to provide high diagnostic performance in determining BMinv. In keeping with earlier research, the current study showed that BMB may not be necessary in every patient at staging, and should be reserved for cases where PET/CT is inconclusive.

Introduction: In breastfeeding women, the indication for scintigraphic imaging is strongly restricted due to potential transition of the radiopharmaceutical to the child via breast milk. The potential activity uptake of the breastfed child depends on the chemical compound of the radio pharmaceutical as well as biokinetics and metabolism in the maternal body.

Methods: In the presented case ^99mTc-MIBI scintigraphy was performed in a breastfeeding woman with sonographically suspicious thyroid nodules. Breastfeeding was interrupted for 30 hours and the breast milk during this period was collected and analysed to determine the excreted activity and the potentially resulting dose to the breastfed child.

Results: Activity concentration in the first breast milk sample (1.83 hours after administration of 500 MBq ^99mTc-MIBI) was 380 Bq/mL, resulting in an absolute activity of 50 kBq for a sample size of 132 mL. Subsequently activity concentration decreased to 6 Bq/mL (29.8 hours p.i.). The calculated effective half-life of the secretion of ^99mTc-MIBI via breast milk was 4.7 hours. The potentially resulting effective dose for the breastfed child was 13.4 µSv (ICRP80: dose coefficient: 0.13 mSv/MBq for ^99mTc).

Conclusion: Time activity curve showed a rapid decrease of the ^99mTc-MIBI activity secreted to the breast milk. More than 90 % of the total secreted activity is attributable to the first 12 hours after administration. Therefore, an interruption of breastfeeding of 24 hours seems to be adequate.

Introduction The present study aims to evaluate the clinical diagnostic value of FDG-PET/CT in patients with inflammation of unknown origin. Material and methods We retrospectively analyzed data of 130 patients who presented general inflammatory symptoms and/or elevated level of CRP and underwent FDG-PET/CT for the purpose of identifying unknown foci of inflammation. The accuracy of PET/CT findings was assessed against the standard of eventual clinical diagnosis e.g. results of pathology, microbiology or other imaging methods. Results In 99/130 patients (76 %) a final diagnosis was established, FDG-PET/CT showed a sensitivity and specificity of each 93 %. A decreased pseudocholinesterase is associated with a higher SUVmax value and with a higher CRP value whereas no significant relationship was found between elevated CRP values and the SUVmax, although higher CRP values are associated significantly with a true positive PET/CT result. Conclusion FDG-PET/CT is a highly sensitive, specific and accurate method for the detection of foci of inflammation of unknown origin. The combination of decreased pseudocholinesterase and increased CRP levels may be a useful tool to select patients for FDG PET/CT.

Aim: To investigate the clinical value of 68Ga-FAPI-04 PET/CT for initial staging of esophageal cancer.

Methods: A total of 44 newly diagnosed patients with esophageal cancer were included in the analysis on the basis of postoperative pathology or clinical and radiologic follow-up.

Results: All primary lesions showed increased 68Ga-FAPI-04 uptake, with an SUVmax of 14.92 ± 6.91. A total of 561 lymph nodes were verified by surgery (507) or clinical and radiologic follow-up (54), of which 92 lymph nodes were diagnosed as showing metastases. Seventy-five lymph nodes with metastases showed positive findings on 68Ga-FAPI-04, with a diameter of about 1.06 ± 0.53 cm and SUVmax of 8.10±4.71. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value for lymph node metastasis detection were 81.5%, 99.3%, 96.6%, 96.2%, and 96.5%, respectively.

Conclusion: 68Ga-FAPI-04 PET/CT showed good diagnostic performance in detecting lymph node metastases of esophageal cancer.

Aim: Thyroid scintigraphy enables the depiction of the functional status of thyroid nodules (TNs) with both, ^99mTc-pertechnetate and ¹²³Iodine. The functional status is relevant for diagnostic procedures for the differentiation of benign and malignant TNs. The aim of this study was to examine the current frequencies of hyper-, hypo- and isofunctioning TNs in Germany and to estimate the risk of malignancy with regard to functional status.

Methods: In 11 study centers, a minimum of 100 nodules per center were consecutively enrolled between July 2019 and April 2020. Inclusion criteria were: newly diagnosed nodule, nodule' size of 10 mm or more, thyroid scintigraphy. Exclusion criteria were: completely cystic TNs, patients with prior radioiodine therapy or thyroid surgery. The risk of malignancy was estimated for hyper- and hypofunctioning TNs.

Results: Overall, 849 patients (72 % women) with 1262 TNs were included. Patients' age ranged from 18 to 90 years. Most TNs were hypofunctioning (n=535, 42%) followed by isofunctioning TNs (n=488, 39%) and hyperfunctioning TNs (n=239, 19%). When only TNs with a maximum size of 2 cm or more were considered the rate of hyperfunctioning and hypofunctioning TNs increased (to 27% and 49%) while isofunctioning TNs decreased. Only one of all hyperfunctioning TNs was malignant. In hypofunctioning nodules, the malignancy rate was estimated at 10%.

Conclusion: In Germany, the proportion of hyperfunctioning TNs is approximately 20% and increases in larger TNs to up to 27%. Due to the low risk of malignancy in hyperfunctioning TNs, no further procedures to rule out malignancy are necessary. The risk of malignancy of hypofunctioning TNs is significantly higher. Thus, a thyroid scintigraphy is a useful diagnostic tool in Germany.

Prostate-specific membrane antigen (PSMA)-directed positron emission tomography (PET) has gained increasing interest for imaging of men affected by prostate cancer (PC). In recent years, ⁶⁸Ga-labeled PSMA compounds have been widely utilized, although there is a trend towards increased utilization of ¹⁸F-labeled agents. Among others, [¹⁸F]DCFPyL (piflufolastat F 18, PYLARIFY) has been tested in multiple major trials, such as OSPREY and CONDOR, which provided robust evidence on the clinical utility of this compound for staging, restaging, and change in management. Recent explorative prospective trials have also utilized [¹⁸F]DCFPyL PET/CT for response assessment, e.g., in patients under abiraterone or enzalutamide, rendering this ¹⁸F-labeled PSMA radiotracer as an attractive biomarker for image-guided strategies in men with PC. After recent approval by the U.S. Food and Drug Administration, one may expect more widespread use, not only in the U.S., but also in Europe in the long term. In the present review, we will provide an overview of the current clinical utility of [¹⁸F]DCFPyL in various clinical settings for men with PC.