Real-Life Performance of F-18-FDG PET/CT in Patients with Cervical Lymph Node Metastasis of Unknown Primary Tumor

Abstract

Background: Neoplasms in the head and neck region possess higher glycolytic activity than normal tissue, showing increased glucose metabolism. F-18-Flourodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) can identify an unknown primary tumor (CUP). Aim: The aim of this study was to assess the real-life performance of F-18-FDG-PET/CT in detecting primary sites in patients with cervical lymph node metastasis of CUP. Methods: A retrospective data analysis of 31 patients who received FDG-PET/CT between June 2009 and March 2015 in a CUP context with histologically confirmed cervical lymph node metastasis was included. Results: In 48% of the patients (15/31), PET/CT showed suspicious tracer accumulation. In 52% of the patients (16/31), there was no suspicious radiotracer uptake, which was confirmed by the lack of identification of any primary tumor in 10 cases until the end of follow-up. FDG-PET/CT had a sensitivity of 67%, specificity of 91%, PPV of 92%, and NPV of 63% in detecting the primary tumor. Additionally, PET/CT showed suspicious tracer accumulation according to further metastasis in 32% of the patients (10/31). Conclusion: FDG-PET/CT imaging is a useful technique for primary tumor detection in patients in a cervical CUP context. Furthermore, it provides information on the ulterior metastasis of the disease.

Utility of 18F-FDG PET/CT in Treatment Strategies for Patients With Cancer of Unknown Primary: A Single-Center, Retrospective Change-in-Management Study

“…All of our patients were histopathologically confirmed with CUP, but in these studies, only some of the patients were histopathologically indicated, which have resulted in the relatively low rates of primary tumor detection on PET/CT. Most patients had tumors in the head and neck and lung, which is consistent with other reports in the literature; 28 , 29 nonetheless, the histopathologic results showed that adenocarcinoma was the most frequent tumor, followed by squamous cell carcinoma. This result may be attributed to the following reason: head and neck tumors include nasopharyngeal cancer, oropharyngeal cancer, laryngeal cancer, and hypopharyngeal cancer, which can contribute to the highest incidence of head and neck cancer in statistics.…”

18F-FDG PET/MRI and 18F-FDG PET/CT for the Management of Gynecological Malignancies: A Comprehensive Review of the Literature

“…For diagnosing CC, five eligible studies utilizing FDG PET/CT and FDG PET/MRI with a total of 188 patients were included [114][115][116][117][118]. The sensitivity and specificity of FDG PET/CT in CC diagnosis ranged from 75% to 86.66% and 44.4% to 96%, respectively [115,118].…”