The aim of this study was to describe the characteristics of positron emission tomography (PET) molecular imaging combined with low-dose computed tomography (CT) in small renal mass (SRM) treated ...with cryoablation (CA). Currently, treatment success is defined by the absence of contrast enhancement at CT. However, the use of contrast is relatively contraindicated in patients with renal function impairment, mandating alternative follow-up strategies. Several reasons were identified as criteria for performing PET-CT before and/or after SRM-CA in 9 patients, and the results were retrospectively studied. The histology revealed renal cell carcinoma in 7 patients and oncocytoma in 2 patients. In 6 patients, a PET-CT was performed before and after CA. In one patient, the PET-CT was performed only before CA and in 2 patients only after CA. Before CA, clearly there was metabolic uptake of fluorine-18 fluorodeoxyglucose (18F-FDG) in the SRM in all patients. Following CA, the absence of 18F-FDG uptakes in the SRM could clearly be noticed. However, the tracer cannot always be distinguished from focal recurrence or reactive inflammatory tissue. In one patient, asymptomatic metastatic bone lesions were noticed when performing PET-CT at follow-up. This pilot study with 18F-FDG PET-CT for the follow-up of SRM cryosurgery showed that 18F-FDG PET-CT imaging could be used to characterize cryoablative tissue injury at different times after CA.
Purpose
The current study explored the association between 2-
18
Ffluoro-2-deoxy-D-glucose (
18
FFDG) uptake and the quantitative expression of immunohistochemical markers related to glucose ...metabolism, hypoxia, and cell proliferation in benign and malignant thyroid nodules of indeterminate cytology.
Procedures
Using a case–control design, 24 patients were selected from participants of a randomized controlled multicenter trial (NCT02208544) in which
18
FFDG-PET/CT and thyroid surgery were performed for Bethesda III and IV nodules. Three equally sized groups of
18
FFDG-positive malignant,
18
FFDG-positive benign, and
18
FFDG-negative benign nodules were included. Immunohistochemical staining was performed for glucose transporters (GLUT) 1, 3, and 4; hexokinases (HK) 1 and 2; hypoxia-inducible factor-1 alpha (HIF1α; monocarboxylate transporter 4 (MCT4); carbonic anhydrase IX (CA-IX); vascular endothelial growth factor (VEGF); sodium-iodide symporter (NIS); and Ki-67. Marker expression was scored using an immunoreactive score. Unsupervised cluster analysis was performed. The immunoreactive score was correlated to the maximum and peak standardized uptake values (SUV
max
, SUV
peak
) and SUV
max
ratio (SUV
max
of nodule/background SUV
max
of contralateral, normal thyroid) of the
18
FFDG-PET/CT using the Spearman’s rank correlation coefficient and compared between the three groups using Kruskal–Wallis tests.
Results
The expression of GLUT1, GLUT3, HK2, and MCT4 was strongly positively correlated with the SUV
max
, SUV
peak
, and SUV
max
ratio. The expression of GLUT1 (
p
= 0.009), HK2 (
p
= 0.02), MCT4 (
p
= 0.01), and VEGF (
p
= 0.007) was statistically significantly different between
18
FFDG-positive benign nodules,
18
FFDG-positive thyroid carcinomas, and
18
FFDG-negative benign nodules. In both
18
FFDG-positive benign nodules and
18
FFDG-positive thyroid carcinomas, the expression of GLUT1, HK2, and MCT4 was increased as compared to
18
FFDG-negative benign nodules. VEGF expression was higher in
18
FFDG-positive thyroid carcinomas as compared to
18
FFDG-negative and
18
FFDG-positive benign nodules.
Conclusions
Our results suggest that
18
FFDG-positive benign thyroid nodules undergo changes in protein expression similar to those in thyroid carcinomas. To expand the understanding of the metabolic changes in benign and malignant thyroid nodules, further research is required, including correlation with underlying genetic alterations.
Full text
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, VSZLJ, ZAGLJ
Laparoscopic evaluation of sentinel nodes is useful for staging prostate cancer, but preoperative localization of deep abdominal sentinel nodes with planar lymphoscintigraphy is difficult. We ...evaluated the value of SPECT/CT for detecting and localizing sentinel nodes in prostate cancer.
(99m)Tc-nanocolloid was injected peri- and intratumorally, guided by transrectal ultrasonography, in 46 patients with prostate cancer of intermediate prognosis. Patients underwent planar imaging after 15 min and 2 h, SPECT/CT after 2 h, and laparoscopic sentinel node lymphadenectomy on the same day. SPECT was fused with CT and analyzed using 2-dimensional orthogonal slicing and 3-dimensional volume rendering. We evaluated the number of extra sentinel nodes found by SPECT/CT, the number of sentinel nodes found by SPECT/CT outside the area of the extended pelvic lymphadenectomy, and the anatomic information provided by SPECT/CT. Furthermore, we classified the value of the additional SPECT/CT images into 3 categories (no advantage, presumable advantage, and definite advantage) according to the extra anatomic information given and whether additional sentinel nodes were found by SPECT/CT.
The patients had a mean age of 64 y (range, 53-74 y) and received a mean injected dose of 218 MBq (range, 147-286 MBq). The sentinel node visualization rate was 91% (42 patients) for planar imaging and 98% (45 patients) for SPECT/CT. In 29 of the 46 patients (63%), SPECT/CT revealed additional sentinel nodes (especially lymph nodes near the injection area) not seen on planar imaging. In 7 patients, those additional sentinel nodes were positive for metastasis (being the exclusive metastatic sentinel node in 4 patients). Overall, 15 patients (33%) had positive sentinel nodes. Sentinel nodes outside the area of extended pelvic lymphadenectomy were found in 16 patients (35%), whereas in 56% of these patients those nodes were not seen on planar imaging. Performing SPECT/CT had no advantage in 13% of the patients, a presumable advantage in 24%, and a definite advantage in 63%. Urologic surgeons used the SPECT/CT images to guide their trocar insertion sites and sentinel node finding with the probe.
More sentinel nodes can be detected with SPECT/CT than with planar imaging alone. In comparison with planar imaging, SPECT/CT especially reveals extra sentinel nodes near the prostate and outside the area of the extended pelvic lymphadenectomy. Furthermore, the modality provides useful additional information about the anatomic location of sentinel nodes within and outside the pelvic area, leading to improved intraoperative sentinel node identification.
The aim of this study was to describe the characteristics of positron emission tomography (PET) molecular imaging combined with low-dose computed tomography (CT) in small renal mass (SRM) treated ...with cryoablation (CA). Currently, treatment success is defined by the absence of contrast enhancement at CT. However, the use of contrast is relatively contraindicated in patients with renal function impairment, mandating alternative follow-up strategies. Several reasons were identified as criteria for performing PET-CT before and/or after SRM-CA in 9 patients, and the results were retrospectively studied. The histology revealed renal cell carcinoma in 7 patients and oncocytoma in 2 patients. In 6 patients, a PET-CT was performed before and after CA. In one patient, the PET-CT was performed only before CA and in 2 patients only after CA. Before CA, clearly there was metabolic uptake of fluorine-18 fluorodeoxyglucose (
F-FDG) in the SRM in all patients. Following CA, the absence of
F-FDG uptakes in the SRM could clearly be noticed. However, the tracer cannot always be distinguished from focal recurrence or reactive inflammatory tissue. In one patient, asymptomatic metastatic bone lesions were noticed when performing PET-CT at follow-up. This pilot study with
F-FDG PET-CT for the follow-up of SRM cryosurgery showed that
F-FDG PET-CT imaging could be used to characterize cryoablative tissue injury at different times after CA.
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![[18F]FDG Uptake and Express...](http://api.summon.serialssolutions.com/2.0.0/image/issn/XR4PS5YY4K/1536-1632/small "[18F]FDG Uptake and Expression of Immunohistochemical Markers Related to Glycolysis, Hypoxia, and Proliferation in Indeterminate Thyroid Nodules")
