Subject(s)
Carcinoma, Squamous Cell/diagnostic imaging , Mandible/diagnostic imaging , Neoplasm Recurrence, Local/diagnostic imaging , Osteoradionecrosis/diagnostic imaging , Tonsillar Neoplasms/diagnostic imaging , Carcinoma, Squamous Cell/therapy , Diagnosis, Differential , Fluorodeoxyglucose F18 , Humans , Male , Middle Aged , Positron-Emission Tomography , Radiopharmaceuticals , Tomography, X-Ray Computed , Tonsillar Neoplasms/therapySubject(s)
Bone Neoplasms/diagnosis , Bone Neoplasms/secondary , Fluorodeoxyglucose F18 , Hyperparathyroidism, Secondary/diagnosis , Hyperparathyroidism, Secondary/pathology , Bone Neoplasms/diagnostic imaging , Bone and Bones/diagnostic imaging , Bone and Bones/metabolism , Bone and Bones/pathology , Diagnosis, Differential , Fluorodeoxyglucose F18/metabolism , Humans , Hyperparathyroidism, Secondary/diagnostic imaging , Male , Middle Aged , Positron-Emission Tomography , Tomography, X-Ray ComputedABSTRACT
OBJECTIVES: In patients with cervical lymph node metastases from unknown primary tumour (UPT), the primary tumour is frequently localized in the head and neck area. Because the detection of the primary tumour is of importance to optimize the patient's management and allows a targeted therapy, the performances of hybrid positron emission tomography-computed tomography (PET-CT) using fluorodeoxyglucose (FDG) were evaluated in a retrospective study. METHODS: Thirty-eight consecutive patients with cervical lymph node metastases, and in whom the primary was not detected by the comprehensive diagnostic work-up including endoscopy and conventional imaging methods, were referred for a PET-CT scan. RESULTS: PET-CT was positive with an increased FDG focal uptake suggesting the potential primary site in 68% of patients (26/38), which guided the biopsies during a second rigid panendoscopy in 17 of these 26 patients: 13 primary tumours were then histologically proven. PET-CT showed distant lesions in three patients. It had treatment-related implications in 23/38 patients (60%), consisting of modification of radiation planning, surgery or abstention from surgery. CONCLUSION: Hybrid FDG-PET-CT is helpful for the detection of a potential head and neck primary tumour. Furthermore, hybrid FDG-PET-CT has the ability to diagnose occult or distant second tumour and metastatic disease and modify patient management.
Subject(s)
Fluorodeoxyglucose F18 , Head and Neck Neoplasms/diagnosis , Head and Neck Neoplasms/secondary , Lymph Nodes/diagnostic imaging , Neoplasms, Unknown Primary/diagnosis , Positron-Emission Tomography/methods , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Cervical Vertebrae/diagnostic imaging , Female , Humans , Image Enhancement/methods , Lymphatic Metastasis , Male , Middle Aged , Radiopharmaceuticals , Reproducibility of Results , Sensitivity and Specificity , Subtraction TechniqueABSTRACT
OBJECTIVE: The aim of this study was to assess the performance of FDG PET/CT for the detection of colonic lesions, especially advanced neoplasms (villous or >10-mm adenomas, carcinomas). Because of 18F FDG accumulation in adenomatous polyps, PET using FDG can detect early premalignant colorectal lesions. MATERIALS AND METHODS: FDG PET/CT studies performed for a 1-year period in 1,716 consecutive patients with various malignant diseases, except colorectal cancer, were retrospectively reviewed. PET images obtained 1 hr after FDG injection and non-contrast CT images used for attenuation correction were fused for analysis. Of 45 patients showing intense focal colonic FDG uptake, 20 patients (with 21 foci) underwent a colonoscopic investigation, and, when necessary, polyp resection. The intensity of FDG uptake was quantified using the standardized uptake value (SUV(max)). RESULTS: The FDG colonic foci were associated with 18 colonoscopic abnormalities in 15 patients, with no colonic abnormality detected in five patients (false-positive [FP] results). Histopathologic findings revealed advanced neoplasms in 13 patients (13 villous adenomas and three carcinomas) and two cases of hyperplastic polyps. A difference in the mean SUV(max) was found between FP and true-positive colonic FDG foci but was not statistically significant (p = 0.14). CONCLUSION: Presence of a focal colonic FDG uptake incidental finding on a PET/CT scan justifies a colonoscopy to detect (pre-)malignant lesions. The fusion of PET and CT images allows an accurate localization of the lesions. PET/CT is a useful tool to differentiate pathologic from physiologic FDG uptake.
