Cmet-26. Diagnostic Value of Fdg-pet/ct for Patients With Brain Metastasis From Unknown Primary Site
Year: 2017
Type: conference-abstract
Abstract: In 30% of patients with brain metastasis (BM), BM are the first clinical manifestation of systemic malignancy, referred to as BM from cancer of unknown primary site (BM-CUPS). The value of 18F-fluordesoxyglucose positron emission tomography (FDG-PET)/CT in the work-up of BM-CUPS patients remains to be defined. We screened 566 patients operated for BM at the University Hospital Zurich between 2004 and 2014 and identified 127 BM-CUPS patients. A validation cohort from two independent centers (n=100 and 120 patients) was available. FDG-PET/CT was not superior to CT in localizing the primary lesion (FDG-PET/CT: 73/78, 93.6%; CT: n=70/78, 89.7%; p=0.25, McNemar’s test). Thirty-six of 64 patients (56.3%) showed the same result in spotting the primary tumor. FDG-PET/CT identified additional lesions suspicious for extracranial metastases in 28 patients (43.7%). The graded prognostic assessment (GPA) score was determined post-hoc to objectify clinical relevance of additional findings. Information from CT only or FDG-PET/CT was used to assess extracranial metastases. Median GPA was 3 for CT vs. 2.5 for PET/CT (p= 3.8x10-5, McNemar’s test), resulting in a predicted survival of 5.3 vs. 3.8 months (p= 6.1x10-5; Wilcoxon’s test). Sensitivity of CT and FDG-PET/CT and staging capabilities were comparable in all cohorts. FDG-PET/CT shows similar sensitivity to detect the primary tumor in BM-CUPS patients as CT, but may improve the accuracy of staging by detecting of more metastases. GPA scores and predicted survival differ significantly when calculated based on CT versus FDG-PET/CT. FDG-PET/CT should be prioritized for planning the diagnostic algorithm of BM-CUPS patients and redundant CT imaging should be avoided. Further, randomized trials on BM patients should standardize the methods when stratifying for GPA.
Source: Neuro-Oncology
Authors: Fabian Wolpert, Michael Weller, Anna Sophie Berghoff, Elisabeth Jane Rushing, Lisa Michaela Füreder, Gregory Petyt, Henning Leske, Nicolaus Andratschke, Luca Regli, Marian Christoph Neidert, Roger Stupp, Rolf Stahel, Reinhard Dummer, Thomas Frauenfelder, Patrick Roth, Nicolas Reyns, Philipp Antonio Kaufmann, Emilie Le Rhun
Language: English
Subfield: Oncology
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W2767236337