RESUMO
BACKGROUND: The use of 18F-FDG Positron emission tomography/Computed tomography (PET/CT) in the initial staging of many cancers is clearly established. Most soft tissue sarcoma (STS) has a high affinity for 18F-FDG, which is why 18F-FDG PET/CT has been proposed as a non-invasive method, useful in diagnosis and follow-up. The standardized uptake value values (SUV), the volume-based metabolic parameters MTV (metabolic tumor volume), and TLG (total lesion glycolysis) determine tumor viability and provide its total volume and the total activity of metabolically active tumor cells. The histological grade is the most important predictor of metastases and mortality associated with STS, and a significant relationship between the metabolic parameters of 18F-FDG PET/CT and the histological grade has been described. METHODS: A retrospective study was conducted on STS patients, who had histological grade according to the FNCLCC (Fédération Nationale des Centres de Lutte Contre Le Cancer) criteria, as well as a baseline PET/CT. SUV (SUVmax, SUVmean, and SUVpeak), MTV, and TLG were quantified. A T-student test was performed to establish the relationship between the metabolic biomarkers and the histological grade. Their usefulness as predictors of the histological grade was verified using receiver operator characteristic (ROC) curves. A survival function study was performed using the Kaplan-Meier method. To assess the prognostic utility of the metabolic biomarkers we use the Log-Rank method. RESULTS: The SUV values were useful to discriminate high-grade STS. We found a significant relationship between the histological grade and the SUV values. SUVmax, SUVpeak, MTV, and TLG were predictors of overall survival (OS). There were no significant differences in the OS for the SUVmean, or in the disease-free survival (DFS) for SUVmax, SUVmean, SUVpeak, MTV, and TLG. CONCLUSIONS: The SUVmax, SUVmean, and SUVpeak values correlate with the HG and are useful to discriminate high-grade from low-grade STS. Patients with high SUVmax, SUVpeak, MTV, and TLG have a significantly lower OS.
RESUMO
INTRODUCCIÓN: El único tratamiento curativo del cáncer de páncreas (CP) es la exéresis quirúrgica, pero debido a su presentación clínica tardía solo el 15-25% de los pacientes son candidatos a resección curativa. El objetivo de este trabajo, prospectivo y unicéntrico, es determinar la utilidad de la PET-TC preoperatoria en el diagnóstico precoz del CP, en su estadificación y en la detección de estadios precursores de la enfermedad en una serie de 139 pacientes sometidos a intervención quirúrgica con «intención curativa» y con el diagnóstico histológico de adenocarcinoma ductal. MÉTODOS: Hemos estudiado las características histopatológicas del CP y de las diferentes lesiones panIN en las piezas quirúrgicas de 139 pacientes sometidos a resección pancreática durante el periodo 2010-2014, comparando estos resultados con los datos preoperatorios de una tomografía computarizada multidetector con contraste trifásico (TCMD) y una PET-TC en la que la captación de glucosa fue determinada por el SUV, considerando malignidad por encima de 2,5. RESULTADOS: En nuestra serie, la sensibilidad de la PET-TC para el diagnóstico tumoral fue del 77,7% (108 de los 139 casos) versus el 75,5% (105 de los 139 casos) para la TCMD. Cuando combinamos este valor máximo del SUV tumoral con el SUV máximo de tejido pancreático normal de cada paciente, la sensibilidad diagnóstica de la PET-TC para el CP asciende al 94,9% (132 de los 139 casos). CONCLUSIÓN: Una combinación de los estudios del PET-TC en el tejido tumoral y no tumoral de cada paciente puede ser una herramienta diagnóstica muy útil no solo para el diagnóstico preoperatorio del CP, sino también para las lesiones panIN
INTRODUCTION: In pancreatic ductal adenocarcinoma (PDA), surgical resection is the only curative treatment, but due to its late clinical presentation only 15-25% patients are candidates for curative resection. The aim of this prospective, single-center study is to determine the diagnostic utility of preoperative PET-CT for early detection of PDA and early panIN lesions. METHODS: We studied the histopathological features of PDA and different panIN lesions in 139 surgical samples from patients undergoing pancreatic resection (from 2010-2014), comparing these results with preoperative PET-CT and MDCT study. For tumor diagnosis in PET-CT maximum standard SUV 2.5 was used. Pancreatic baseline SUVmax is the maximum uptake of the radiotracer 18-2FDG on the ROI curve determined for the area of the normal pancreas after pathological reassessment with areas not affected by tumours or preneoplastic lesions. Tumour Uptake Index is the ratio between the tumour SUVmax and pancreatic baseline SUVmax. RESULTS: Using an standard maximum SUV value of 2.5, PET-CT sensitivity was 77.7% (108 of the 139 cases) against 75.5% (105 of the 139 cases) of MDCT. But when we combined this value with maximum SUV of normal pancreatic tissue from each patient, PET-CT sensitivity improved its value to 94.9%. CONCLUSION: A combination of studies of PET-CT in tumor and non-tumor tissue of each patient might be a very useful diagnostic tool not only for preoperative diagnosis of PDA, but also for early panIN lesions
Assuntos
Humanos , Tomografia por Emissão de Pósitrons/métodos , Neoplasias Pancreáticas/diagnóstico , Pâncreas Exócrino/patologia , Pancreatectomia/métodos , Carcinoma Ductal Pancreático/diagnóstico , Fluordesoxiglucose F18 , Detecção Precoce de Câncer/métodos , Sensibilidade e Especificidade , Adenocarcinoma in Situ/cirurgia , Carcinoma Ductal Pancreático/cirurgiaRESUMO
INTRODUCTION: In pancreatic ductal adenocarcinoma (PDA), surgical resection is the only curative treatment, but due to its late clinical presentation only 15-25% patients are candidates for curative resection. The aim of this prospective, single-center study is to determine the diagnostic utility of preoperative PET-CT for early detection of PDA and early panIN lesions. METHODS: We studied the histopathological features of PDA and different panIN lesions in 139 surgical samples from patients undergoing pancreatic resection (from 2010-2014), comparing these results with preoperative PET-CT and MDCT study. For tumor diagnosis in PET-CT maximum standard SUV 2.5 was used. Pancreatic baseline SUVmax is the maximum uptake of the radiotracer 18-2FDG on the ROI curve determined for the area of the normal pancreas after pathological reassessment with areas not affected by tumours or preneoplastic lesions. Tumour Uptake Index is the ratio between the tumour SUVmax and pancreatic baseline SUVmax. RESULTS: Using an standard maximum SUV value of 2.5, PET-CT sensitivity was 77.7% (108 of the 139 cases) against 75.5% (105 of the 139 cases) of MDCT. But when we combined this value with maximum SUV of normal pancreatic tissue from each patient, PET-CT sensitivity improved its value to 94.9%. CONCLUSION: A combination of studies of PET-CT in tumor and non-tumor tissue of each patient might be a very useful diagnostic tool not only for preoperative diagnosis of PDA, but also for early panIN lesions.
