ABSTRACT
INTRODUCTION: The expanding use of 18F-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET-CT) has resulted in an increased frequency of incidentally discovered areas of FDG uptake within the thyroid gland. In these incidentalomas, high malignancy rates are reported. The study aimed, on the one hand, to determine the prevalence in our setting of thyroid incidentalomas in patients with no previous history of thyroid cancer undergoing an FDG PET-CT as well as the risk of malignancy and, on the other hand, to evaluate the usefulness of the maximum standard uptake value (SUVmax) for detecting thyroid cancer. MATERIAL AND METHODS: The FDG PET-CT scans performed at our hospital between June 2013 and December 2020 were retrospectively reviewed. In those incidentalomas with sufficient additional investigation, a diagnosis of benign or malignant was established based on the complementary tests. RESULTS: From the 21,594 PET-CT scans performed, 398 (1.8%) patients had an incidental FDG uptake, either focal (n=324) or diffuse (n=74). Among incidentalomas with further investigation, the rate of malignancy was higher in patients with focal FDG uptake than in those with diffuse uptake (26.5% versus 4%, respectively, p<0.05). The SUVmax value was significantly lower in benign focal lesions (5.7 [range: 2.3-66] than in malignant ones 10.6 [range: 3.1-51.2]; p<0.05). Nearly a quarter of malignant diagnoses (23.3%) were related to potentially aggressive tumours. CONCLUSION: The high rate of malignant tumours found among PET-CT incidentalomas and the high proportion of aggressive tumours demonstrate the need for a standardised approach in the investigation of incidental focal FDG uptake in the thyroid gland.
Subject(s)
Positron Emission Tomography Computed Tomography , Thyroid Neoplasms , Humans , Fluorodeoxyglucose F18 , Retrospective Studies , Prevalence , Clinical Relevance , Incidental Findings , Thyroid Neoplasms/diagnostic imaging , Thyroid Neoplasms/epidemiologyABSTRACT
Objetivo Valorar la utilidad clínica de los criterios PERCIST y de los cambios en los parámetros cuantitativos de la PET/TC con [18F]FDG como factores pronósticos para la supervivencia libre de progresión y la supervivencia cáncer-específica en pacientes con cáncer de esófago tratados mediante quimiorradioterapia. Material y métodos Se valoraron retrospectivamente 50 pacientes (48 hombres) diagnosticados de cáncer de esófago durante un intervalo de 7,5 años. Se utilizaron los criterios PERCIST para valorar la respuesta a la neoadyuvancia. Asimismo, se determinaron las variaciones del SUV máximo, volumen metabólico tumoral y glucólisis tumoral total entre los estudios PET/TC pre- y postratamiento. Las curvas ROC, el método de Kaplan-Meier y el modelo de regresión de Cox se aplicaron para el análisis de factores pronósticos y curvas de supervivencia. Resultados El seguimiento medio fue de 26,8 meses, produciéndose 40 recurrencias-progresiones y 41 muertes. El análisis de supervivencia mostró curvas de supervivencia cáncer-específica con diferencias estadísticamente significativas en relación con los criterios PERCIST y la variación del volumen metabólico tumoral y la glucólisis tumoral total. Los criterios PERCIST fueron el único factor predictivo independiente en el análisis multivariante. Ni el SUV máximo ni el tamaño tumoral fueron predictores para ninguno de los criterios de evaluación. Conclusión La aplicación de los criterios PERCIST, así como el cambio de volumen metabólico tumoral y glucólisis tumoral total de los estudios PET/TC demostraron ser factores pronósticos para la supervivencia cáncer-específica en pacientes de nuestro entorno tratados por cáncer de esófago. Los resultados podrían ayudar a personalizar el tratamiento (AU)
Aim To assess the clinical utility of PERCIST criteria and changes in [18F]FDG PET/CT quantitative parameters as prognostic factors for progression-free survival and cancer-specific survival in patients with esophageal cancer treated by chemoradiotherapy. Material and methods Fifty patients (48 men) diagnosed with esophageal cancer were retrospectively evaluated over a 7.5-year interval. PERCIST criteria were used to assess response to neoadjuvant therapy. Variations in the metabolic parameters maximum SUV, metabolic tumor volume and total lesion glycolysis between pre- and post-treatment PET/CT studies were also determined. ROC curves, Kaplan-Meier method and Cox regression model were used for the analysis of prognostic factors and survival curves. Results The average follow-up was 26.8 months, with 40 recurrences-progressions and 41 deaths. Survival analysis showed statistically significant differences in cancer-specific survival curves for PERCIST criteria and variation of metabolic tumor volume and total lesion glycolysis. PERCIST criteria were the only independent predictor in the multivariate analysis. Neither maximum SUV nor tumor size were predictors for any of the assessment criteria Conclusion Application of PERCIST criteria as well as change in metabolic tumor volume and total lesion glycolysis from PET/CT studies proved to be prognostic factors for cancer-specific survival in patients in our setting treated for esophageal cancer. The results could help to personalize treatment (AU)
Subject(s)
Humans , Male , Female , Middle Aged , Aged , Esophageal Neoplasms/diagnostic imaging , Esophageal Neoplasms/therapy , Fluorodeoxyglucose F18/metabolism , Positron-Emission Tomography , Radiopharmaceuticals , Neoadjuvant Therapy , Chemoradiotherapy , PrognosisABSTRACT
OBJECTIVE: To demonstrate the utility of (18)F-FDG PET/CT in the differentiation of benign and malignant solitary fibrous tumors of the pleura (SFTP). MATERIALS AND METHODS: A retrospective review was performed on the (18)F-FDG PET/CT data from 17 patients with histopathologically diagnosed benign or malignant SFTP. The size, side of SFTP, presence of necrosis, calcification, pleural effusion, hilar lymphadenopathy (LAP), density on CT images (Hounsfield unit-HU), and (18)F-FDG uptake (SUVmax) were recorded and compared in order to detect malignant SFTP. Statistical significance was set as p<0.05. RESULTS: The difference in size, presence of necrosis, and hilar LAP on CT images were statistically significant (p=0.004, p<0.001, p=0.015, respectively) in a comparison of benign and malignant SFTPs. The mean HU of benign SFTP was 46.16±5.52HU, and for malignant SFTP it was 35.03±4.61HU (p=0.003). The mean SUVmax was 3.02±1.02 for benign SFTP and 4.89±2.12 for malignant SFTP (p=0.021). A cut-off value of ≥7cm for size, ≤39.81HU for density, and ≥3.47 for SUVmax was obtained by ROC analysis for detecting malignant SFTP. CONCLUSIONS: (18)F-FDG PET/CT may have a limited role in diagnosing malignant SFTP in suspected patients.
