ABSTRACT
BACKGROUND: Staging of mediastinal lymph nodes in non-small cell lung cancer (NSCLC) is mandatory. The maximum Standard Uptake Value (SUVmax) obtained using F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) is the best non-invasive technique available for this evaluation, but its performance varies from center to center. The aim of the present study was to identify FDG-PET predictors of mediastinal malignancy that are able to minimize intercenter variability and improve the selection of subsequent staging procedures. METHOD: A multicenter study of NSCLC patients staged through FDG-PET and endobronchial ultrasonography with needle aspiration (EBUS-NA) was performed using therapeutic surgery with systematic nodal dissection as gold standard. Intercenter variability and predictive power for mediastinal malignancy of different FDG-PET measures were assessed, as well as the role of these measures for selecting additional staging procedures. RESULTS: One hundred and twenty-one NSCLC patients, of whom 94 (72%) had ≥1 hypermetabolic spots in the mediastinum, were included in the study. Mean SUVmax of the primary tumor was 12.3 (SD 6.3), and median SUVmax of the highest hypermetabolic spots in the mediastinum was 3.9 (IQR 2.4-7). Variability of FDG-PET measures between hospitals was statistically significant (p = 0.016 and p < 0.001 respectively), but lost significance when SUVmax in the mediastinum was expressed as a ratio or a subtraction from the primary tumor (SUVmax mediastinum/tumor, p = 0.083; and SUVmax mediastinum - tumor, p = 0.428 respectively). SUVmax mediastinum/tumor showed higher accuracy in the ROC analysis (AUC 0.77 CI 0.68-0.85, p < 0.001), and showed predictive power for mediastinal malignancy when using a 0.4 cutoff (OR 6.62, 95%CI 2.98-14.69). Sensitivities and negative predictive values of clinical staging through EBUS-NA attained values ranging between 57% and 92% after FDG-PET, which improved with additional techniques when the tumor had a diameter >3 cm and/or a SUVmax mediastinum/tumor ratio >0.4. CONCLUSION: The SUVmax mediastinum/tumor ratio is a good predictor of regional tumor extension in NSCLC. This measure is not influenced by intercenter variability and has an accuracy of over 70% for the identification of malignancy when using a 0.4 cutoff.
Subject(s)
Carcinoma, Non-Small-Cell Lung/pathology , Lung Neoplasms/pathology , Mediastinal Neoplasms/diagnostic imaging , Mediastinal Neoplasms/secondary , Positron-Emission Tomography , Aged , Endoscopic Ultrasound-Guided Fine Needle Aspiration , Female , Fluorodeoxyglucose F18 , Humans , Logistic Models , Lymph Nodes/diagnostic imaging , Lymph Nodes/pathology , Male , Mediastinum/diagnostic imaging , Mediastinum/pathology , Middle Aged , Neoplasm Staging , Prospective Studies , ROC Curve , SpainABSTRACT
Objetivo. Los pacientes pediátricos con infección del tracto urinario (ITU) tienen riesgo de desarrollar lesiones renales. Aunque el reflujo vesicoureteral (RVU) predispone a ITU y parece tener un papel importante en el desarrollo de estas lesiones, estudios recientes cuestionan dicha relación. El objetivo del estudio fue evaluar mediante gammagrafía renal con 99mTc-DMSA la existencia de lesiones renales y su relación con la presencia o no de RVU. Material y métodos. Se evaluaron retrospectivamente 230 pacientes (460 unidades renales), edad media 11 meses (intervalo: 12 días-5 años), con ITU probada mediante urinocultivo. A todos ellos se les realizó cistografía miccional seriada (CUMS) para valorar la existencia o no de RVU. Para determinar si la ITU originó cicatrices se practicó 99mTc-DMSA a partir de los 6 meses postinfección. Resultados. El estudio con 99mTc-DMSA de control postinfección fue patológico en 62 unidades renales, afectando a 54 pacientes (23 %). De los pacientes estudiados, 110 fueron diagnosticados de RVU, afectando a 161 unidades renales, de las cuales 43 unidades (27 %) presentaron cicatrices. De los restantes 120 pacientes sin RVU, 240 unidades renales, 19 de ellas (8 %) presentaron afectación renal. Conclusión. Las cicatrices renales post-ITU están en algunos casos relacionadas con RVU, pero en ocasiones se asocian a la propia infección. No todos los pacientes con RVU desarrollan lesiones y su presencia no siempre predispone a mayor susceptibilidad a lesiones renales. La CUMS o cistografía isotópica directa son útiles para diagnosticar RVU, pero no deberíamos obviar el estudio con 99mTc-DMSA en el manejo del paciente con ITU
Objective. Paediatric patients with urinary tract infection (UTI) have risk of developing renal scarrings. Although it is known that vesicoureteral reflux (VUR) predisposes to UTIs and it seems to have an important role in the development of renal lesions, some recent published studies question that relation. The aim of the study was to evaluate renal scarring by using renal scintigraphy 99mTc-DMSA and see the relation with or without the presence of VUR. Material and methods. We evaluated retrospectively a total of 230 patients (460 renal units), mean age: 11 months (range: 12d-5y), with UTI probed by urinoculture. All were studied with voiding cistourethrography (MCU) to evaluate the presence or absence of VUR. Patients were evaluated with 99mTc-DMSA scan 6 months after UTI to determine if UTI caused renal scarring. Results. Renal scans with 99mTc-DMSA 6 months post-infection were abnormal in 62 renal units, affecting 54 patients (23 %). From all patients studied, 110 were diagnosis of VUR being affected 161 renal units, 43 of them (27 %) presented renal scarrings. From the remaining 120 patients without VUR that is 240 renal units, 19 of them (8 %) presented parenchymatous damage. Conclusion. Renal scarring resulting from UTI are in some cases related to VUR, but sometimes are caused by the infection itself. Not all patients with VUR develop renal lesions, and neither the presence of VUR always predispose children to renal lesions. MCU and direct isotopic cystography are useful for diagnosis of VUR but we shouldn't avoid 99mTc-DMSA scan in the management of children with UTI
