The aims of this study were to investigate the detection of cervical lymph node metastases of head and neck cancer by positron emission tomographic (PET) imaging with fluorine-18 fluorodeoxyglucose (FDG) and to perform a prospective comparison with computed tomography (CT), magnetic resonance imaging (MRI), sonographic and histopathological findings. Sixty patients with histologically proven squamous cell carcinoma were studied by PET imaging before surgery. Preoperative endoscopy (including biopsy), CT, MRI and sonography of the cervical region were performed in all patients within 2 weeks preceding 18F-FDG whole-body PET. FDG PET images were analysed visually and quantitatively for objective assessment of regional tracer uptake. Histopathology of the resected neck specimens revealed a total of 1284 lymph nodes, 117 of which showed metastatic involvement. Based on histopathological findings, FDG PET correctly identified lymph node metastases with a sensitivity of 90% and a specificity of 94% (P<10(-6)). CT and MRI visualized histologically proven lymph node metastases with a sensitivity of 82% (specificity 85%) and 80% (specificity 79%), respectively (P<10(-6)). Sonography revealed a sensitivity of 72% (P<10(-6)). The comparison of 18F-FDG PET with conventional imaging modalities demonstrated statistically significant correlations (PET vs CT, P = 0.017; PET vs MRI, P = 0.012; PET vs sonography, P = 0.0001). Quantitative analysis of FDG uptake in lymph node metastases using body weight-based standardized uptake values (SUVBW) showed no significant correlation between FDG uptake (3.7+/-2.0) and histological grading of tumour-involved lymph nodes (P = 0.9). Interestingly, benign lymph nodes had increased FDG uptake as a result of inflammatory reactions (SUVBW-range: 2-15.8). This prospective, histopathologically controlled study confirms FDG PET as the procedure with the highest sensitivity and specificity for detecting lymph node metastases of head and neck cancer and has become a routine method in our University Medical Center. Furthermore, the optimal diagnostic modality may be a fusion image showing the increased metabolism of the tumour and the anatomical localization.
Scintigraphy using [111In-DTPA-d-Phe1]-pentetreotide or pentavalent technetium-99m-dimercaptosuccinic acid [99mTc(V)-DMSA] has been shown to localize well-differentiated and slowly growing neuroendocrine tumours, whereas increased fluorodeoxyglucose (FDG) uptake is associated with malignancy. The aim of this study was to compare the value of fluorine-18 FDG positron emission tomography (PET) with that of somatostatin receptor scintigraphy (SS-R) and dual-radionuclide scintigraphy [SS-R and 99mTc(V)-DMSA = DNS] in detecting malignant neuroendocrine tumours. Fifteen patients with metastasizing gastroenteropancreatic tumours (GEP tumours; n = 7), medullary thyroid carcinomas (MTCs; n = 8) and elevated tumour markers [GEP tumours: 5-hydroxyindoleacetic acid, insulin; MTCs: calcitonin, carcinoembryonic antigen (CEA)] were studied. Prior to PET, all patients with GEP tumours underwent SS-R. DNS was performed in all patients with MTC. Patients had been fasting for at least 12 h and normal glucose plasma levels were confirmed. Sixty minutes after intravenous administration of 18F-FDG (mean: 374 MBq) whole-body PET and regional scans were performed. In addition, the resected tissues were prepared for immunocytochemistry examination (cell cycle-associated Ki-67 antigen). In two patients with less-differentiated GEP tumours associated with high proliferative activity and increased FDG uptake, SS-R failed to detect any lesion. In comparison, in four patients with well-differentiated GEP tumours showing low proliferative activity, SS-R localized four primary tumours, 22 lymph node metastases and 18 malignant liver lesions, whereas 18F-FDG PET demonstrated normal distribution. In one patient with a metastasizing carcinoid (medium proliferative activity) SS-R localized multiple metastases, whereas PET demonstrated low FDG uptake in all known metastases. In patients with recurrent MTC and rapidly increasing CEA levels DNS detected only three lesions in two patients, whereas PET demonstrated one pulmonary, three osseous, 20 mediastinal, ten locoregional, and four liver metastases in seven patients. Twenty-nine malignant lesions were confirmed by follow-up and nine lymph node metastases could be surgically removed. In conclusion, PET imaging of gastroenteropancreatic tumours revealed increased glucose metabolism only in less-differentiated GEP tumours with high proliferative activity and metastasizing MTC associated with rapidly increasing CEA levels. Therefore, additional 18F-FDG PET should be performed only if SS-R or DNS is negative.
ported to be a sensitive method for detecting malignant melanoma metastases. METHODS. One hundred consecutive patients with high risk melanoma (tumor Gustav RESULTS.In Group A, the sensitivity of PET was 100% and the specificity was 94%, whereas CD did not identify any of the 9 lymph node metastases and demonstrated 2 Department of Nuclear Medicine, University of Frankfurt Medical Center, Frankfurt, Germany.a lower specificity (80%). In Group B, 121 lesions were detected, 111 by PET and 69 by conventional imaging. On the basis of patients, the sensitivity, specificity, and accuracy of PET were 100%, 95.5%, and 97.9%, respectively (91.8%, 94.4%, and 92.1%, respectively, on the basis of single metastases). Prospectively, CD did not identify all patients with progression (sensitivity, 84.6%) and detected significantly fewer metastases (sensitivity, 57.5%) with much lower specificity (68.2% on the basis of patients, 45% on the basis of single lesions); therefore, the accuracy of CD was 77.1% on the basis of patients and only 55.7% on the basis of single metastases.Results also depended on specific sites: while PET yielded a higher sensitivity in detecting cervical metastases (100% vs. 66.6%) and abdominal metastases (100% vs. 26.6%), computed tomography proved to be superior in detecting small lung metastases (87% vs. 69.6%). utaneous malignant melanoma causes more than 75% of all skin cancer deaths, and its incidence is rapidly rising in white popula- hand, when managing patients with advanced tumors bearing a high risk for locoregional or systemic spread, one major objective is the CONCLUSIONS. PET is a highly sensitive and
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.