title: Defining risk groups of patients with cancer of unknown primary site and cervical nodal metastases by F-18 fluorodeoxyglucose positron emission tomography and computed tomography imaging.
abstract: We sought to investigate the clinical utility of F-18 fluorodeoxyglucose (FDG) positron emission tomography and computed tomography (PET/CT) in Taiwanese patients with cancer of unknown primary site (CUP) and cervical nodal metastases. We also aimed to study the impact of F-18 FDG PET/CT on clinical treatment priority in this patient group. Between September 2006 and May 2014, patients with CUP and cervical nodal metastases who underwent F-18 FDG PET/CT imaging study were retrospectively identified. The clinicopathological risk factors and PET parameters were analyzed in relation to 2-year overall survival (OS) rates using univariate and multivariate analyses. Two-year OS curves were plotted with the Kaplan-Meier method. Of the eligible patients (n = 54), 12 (22.2%) had distant metastases (DM) at presentation. A total of 13 (24.1%) and 15 (27.8%) primary tumors were identified by FDG PET/CT imaging and an additional triple biopsy, respectively. The results of multivariate analysis identified smoking [p = 0.033, 95% confidence interval (CI) = 1.197-40.342], a maximum standardized uptake value (SUVmax) of cervical nodes ≥ 14.2 (p = 0.035, 95% CI = 1.134-28.029), and DM at presentation (p = 0.031, 95% CI = 1.257-114.854) as independent predictors of 2-year OS. Specifically, patients who carried ≥ 2 risk factors showed poorer outcomes (70.3% vs. 11.8%, p < 0.001). Fifteen study patients (27.8%) had their treatment modified by FDG PET/CT findings. We conclude that FDG PET/CT is clinically useful in CUP patients not only for tumor staging, but also for modifying treatment regimens.
authors: Department of Nuclear Medicine, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan.
authors: Yung-Yueh
authors: YY
authors: Su
authors: Department of Nuclear Medicine, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan.
authors: Shih-Shin
authors: SS
authors: Chen
authors: Department of Medical Oncology, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan; Department of Head and Neck Oncology Group, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan.
authors: Chia-Hsun
authors: CH
authors: Hsieh
authors: Department of Head and Neck Oncology Group, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan; Department of Otorhinolaryngology, Head and Neck Surgery, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan.
authors: Chun-Ta
authors: CT
authors: Liao
authors: Department of Head and Neck Oncology Group, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan; Department of Radiation Oncology, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan.
authors: Chien-Yu
authors: CY
authors: Lin
authors: Department of Head and Neck Oncology Group, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan; Department of Otorhinolaryngology, Head and Neck Surgery, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan.
authors: Chung-Jan
authors: CJ
authors: Kang
authors: Department of Head and Neck Oncology Group, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan; Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan. Electronic address: yentc1110@gmail.com.
authors: Tzu-Chen
authors: TC
authors: Yen
mesh_terms: D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000737:chemistry*; D006801:Humans; D008207:Lymphatic Metastasis / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D008875:Middle Aged; D015999:Multivariate Analysis; D009382:Neoplasms, Unknown Primary / Q000473:pathology*; D000072078:Positron Emission Tomography Computed Tomography; D018570:Risk Assessment; D012307:Risk Factors; D016019:Survival Analysis
chemical_list: D019788:Fluorodeoxyglucose F18
keywords: Head and neck neoplasm; PET scan; Unknown primary tumors