Aims and objectives
Demonstrate the utility of 18F-FDG PET CT for the localization of tumors of unknown primary origin.
Assess the most common histopathological lineage of primary tumor detected by 18F-FDG PET-CT in our hospital.
Methods and materials
*Retrospective,
cross-sectional,
descriptive study.
*83 patients referred to the PET-CT department with clinical diagnosis of probable unknown primary tumor were included.
*PET-CT findings were correlated with the results of follow-up and/or histopathology report.
Results
The results obtained in this study were concordant with the literature,
being the negative predictive value of PET-CT the highest value in case of patients with tumors of unknown origin; all this can be attributable to the poor indication of PET-CT (without a previous exhaustive clinical study or without previous biopsy).
The most common histopathological lineage of primary tumor detected by 18F-FDG PET-CT in our hospital was poorly differentiated adenocarcinoma.
Conclusion
Despite the high rate of false positives,
the detection of true positives is important,
for this reason PET-CT is considered useful for the evaluation of patients with suspected metastatic tumors of unknown origin; increasing its value when it correlates with the clinical assessment and there is a well-founded suspicion.
References
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Combined FDG-PET/CT for the detection of unknown primary tumors: systematic review and meta-analysis.
Eur Radiol (2009) 19:731–744.
Jong Sun Park,
Jae-Joon Yim,
Won Jun Kang,
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Detection of primary sites in unknown primary tumors using FDG-PET or FDG-PET/CT.
Park et al.
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Mehrdad Bakhshayeshkaram,
Mohsen Ghobadi,
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Farahnaz Aghahosseini. Diagnostic Performance of F-18 FDG PET/CT in Patients with Cancer of Unknown Primary: Additional Benefit over CT-Based Conventional Work...