EBUS-TBNA for mediastinal staging of centrally located T1N0M0 non-small cell lung cancer clinically staged with PET/CT.

BACKGROUND AND OBJECTIVE: To evaluate the diagnostic accuracy and clinical usefulness of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for mediastinal staging of centrally located T1N0M0 non-small cell lung cancer (NSCLC) clinically staged with positron emission tomography/computed tomography (PET/CT). METHODS: We conducted a study that included patients with centrally located T1N0M0 NSCLC, clinically staged with PET/CT who underwent EBUS-TBNA for mediastinal staging. Patients with negative EBUS-TBNA underwent mediastinoscopy, video-assisted mediastinoscopic lymphadenectomy (VAMLA) and/or lung resection with systematic nodal dissection, that were considered the gold standard. The sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), overall accuracy of EBUS-TBNA for diagnosing mediastinal metastases (N2 disease) and the number needed to treat (NNT: number of patients needed to undergo EBUS-TBNA to avoid a case of pathologic N2 disease after resection) were calculated. RESULTS: One-hundred eighteen patients were included. EBUS-TBNA proved N2 disease in four patients. In the remaining 114 patients who underwent mediastinoscopy, VAMLA and/or resection there were two cases of N2 (N2 prevalence 5.1%). The sensitivity, specificity, NPV, PPV and overall accuracy for diagnosing mediastinal metastases (N2 disease) were of 66%, 100%, 98%, 100% and 98%, respectively. The NNT was 31 (95% CI: 15-119). CONCLUSION: EBUS-TBNA in patients with central clinically staged T1N0M0 NSCLC presents a good diagnostic accuracy for mediastinal staging, even in a population with low prevalence of N2 disease. Therefore, its indication should be considered in the management of even these early lung cancers.

Evaluation of the endothelial function in hypertensive patients with 13N-ammonia PET.

BACKGROUND: Essential hypertension is one of the main risk factors for the development of coronary artery disease (CAD). Hypertension causes endothelial dysfunction which is considered an early sign for the development of CAD. Positron emission tomography is a non-invasive imaging technique that measures myocardial blood flow (MBF), allowing us to identify patients with endothelial dysfunction. METHODS AND RESULTS: 19 patients without comorbidities recently diagnosed hypertensive, as well as 21 healthy volunteers were studied. A three-phase (rest, cold pressor test, and adenosine-induced hyperemia) (13)N-ammonia PET was performed, and MBF was measured. Endothelial-Dependent Vasodilation Index, ΔMBF, and coronary flow reserve (CFR) were calculated for each patient. Hypertensive patients had a significantly higher systolic and diastolic blood pressures compared with the control group (134.6 ± 11.7/86.4 ± 10.6 mm Hg and 106.0 ± 11.8/71.4 ± 6.6 mm Hg, respectively, P < .001). The ENDEVI (1.28 ± 0.26 vs 1.79 ± 0.30, P < .001), the ΔMBF (0.81 ± 0.50 vs 0.25 ± 0.21, P < .001) and the CFR (2.18 ± 0.88 vs 3.17 ± 0.68, P = .001) were significantly lower in the hypertensive patients compared to the control group, 84% of the former group had endothelial dysfunction i.e., ENDEVI < 1.5 and 58% had vasomotor abnormalities, i.e., CFR < 2.5. CONCLUSIONS: In this study, we showed that recently diagnosed hypertensive patients have coronary endothelial dysfunction and vasomotor disturbances which are early signs for the development of CAD.

[The importance of myocardial blood flow quantification with positron emission tomography (PET) in patients with three-vessel disease]. / Importancia de la cuantificación del flujo coronario mediante PET, en pacientes con enfermedad trivascular.

The study of patients with coronary artery disease by means of gated SPECT has been well established. One of the major limitations of this technique is the detection of myocardial perfusion defects in the presence of multivessel or three-vessel coronary artery disease due to balanced ischemia. Quantification of myocardial blood flow by positron emission tomography allows not only to study cardiac perfusion and function but also to determine the coronary flow reserve which has a better correlation with significant stenosis in patients with trivascular disease. The aim of this study was to demonstrate through a case report and literature review the importance of performing quantification of coronary blood flow in this group of patients.

Importancia de la cuantificación del flujo coronario mediante PET, en pacientes con enfermedad trivascular / The importance of myocardial blood flow quantification with positron emission tomography (PET) in patients with three-vessel disease

El estudio de perfusión miocárdica mediante tomografía computada por emisión de fotón único es una técnica ampliamente aceptada con alta sensibilidad y especificidad. Una de las limitaciones de esta técnica es el diagnóstico de enfermedad trivascular, debido al fenómeno de hipoperfusión global balanceada. La adición de los estudios con tomografía por emisión de positrones, permite no sólo el análisis de la perfusión y de la función ventricular, sino también la cuantificación del flujo coronario en mL/g/min de tejido miocárdico y por lo tanto, la determinación de la reserva de flujo coronario, la cual se ha relacionado claramente con la presencia de estenosis coronaria. El propósito de este trabajo es demostrar a través de un caso clínico y revisión de la literatura médica, la importancia del estudio del flujo coronario de forma no invasiva en los pacientes con enfermedad trivascular.

The study of patients with coronary artery disease by means of gated SPECT has been well established. One of the major limitations of this technique is the detection of myocardial perfusion defects in the presence of multivessel or three-vessel coronary artery disease due to balanced ischemia. Quantification of myocardial blood flow by positron emission tomography allows not only to study cardiac perfusion and function but also to determine the coronary flow reserve which has a better correlation with significant stenosis in patients with trivascular disease. The aim of this study was to demonstrate through a case report and literature review the importance of performing quantification of coronary blood flow in this group of patients.

[PET evaluation of inflammatory process in Takayasu's arteritis]. / Determinación de actividad inflamatoria en pacientes con arteritis de Takayasu mediante tomografía por emisión de positrones (PET).

OBJECTIVE: To determine the application of PET in monitoring patients with Takayasu's arteritis (TA) with Inflammatory activiti (IA) and this correlation with established clnical criteria. METHODS: 35 patients diagnosed with TA were enrolled. Determination of erythrocyte sedimentation rate, C -reactive protein, fibrinogen and a complete blood count was performed and clinical criteria of activity were applied. A baseline PET was performed in all patients. Those who were positive for IA received drug treatment. Among the group of active patients, ten were randomized to undergo another PET scan and clinical criteria determination to evaluate inflammatory activity after 6 months of treatment. We compared clinical criteria with PET capacity to determine IA. The results between the initial and final PET were finally compared. RESULTS: Clinical criteria had a sensitvity of 63% and a specificity of 90% to show IA. Sensivity decreased after 6 months of treatment to 27%. DISCUSSION: This is the first prospective study that compares the findings of PET before and after treatment for IA in patients with TA. Clinical criteria lack sensitivity for the detection of IA in the follow-up after treatment. CONCLUSIONS: PET is a diagnostic technique with high sensitivity and specificity for the diagnosis and monitoring of patients with TA and inflammatory activity.

Determinación de actividad inflamatoria en pacientes con arteritis de Takayasu mediante tomografía por emisión de positrones (PET) / PET evaluation of inflammatory process in Takayasu's arteritis

Objetivos: Determinar la aplicación que tiene la tomografía por emisión de positrones en el seguimiento de pacientes con arteritis de Takayasu con actividad inflamatoria y su correlación con los criterios clínicos establecidos. Métodos: Se incluyeron 35 pacientes con diagnóstico de arteritis de Takayasu. Se determinó velocidad de sedimentación globular, proteína C reactiva, biometría hemática, así como, fibrinógeno y se aplicaron los criterios clínicos de actividad. Se realizó tomografía por emisión de positrones basal de los pacientes positivos para actividad inflamatoria, todos recibieron tratamiento farmacológico. De forma aleatoria se incluyó a 10 pacientes que posterior al tratamiento durante seis meses se les realizó un nuevo estudio clínico y una tomografía por emisión de positrones para determinar actividad inflamatoria. Se compararon los criterios clínicos con tomografía por emisión de positrones tanto del estudio basal como el de seguimiento. Resultados: Los criterios clínicos tuvieron una sensibilidad de 63% y especificidad de 90% para demostrar actividad inflamatoria en forma basal. La sensibilidad de los criterios clínicos disminuyó posterior al tratamiento hasta 27%, en donde se observó que pacientes aparentemente inactivos por clínica, continuaban activos por tomografía por emisión de positrones. Discusión: Éste es el primer estudio que compara de manera prospectiva los hallazgos de tomografía por emisión de positrones antes y después del tratamiento para actividad inflamatoria en pacientes con arteritis de Takayasu. Los criterios clínicos carecen de sensibilidad para la detección de actividad inflamatoria en el seguimiento posterior al tratamiento. Conclusiones: El tomografía por emisión de positrones es una técnica de diagnóstico con una alta sensibilidad y especificidad para el diagnóstico y seguimiento de pacientes con arteritis de Takayasu y actividad inflamatoria.

Objective: To determine the application of PET in monitoring patients with Takayasu's arteritis (TA) with inflammatory activity (IA) and its correlation with established clinical criteria. Methods: 35 patients diagnosed with TA were enrolled. Determination of erythrocyte sedimentation rate, C-reactive protein, fibrinogen and a complete blood count was performed and clinical criteria of activity were applied. A baseline PET was performed in all patients. Those who were positive for IA received drug treatment. Among the group of active patients, ten were randomized to undergo another PET scan and clinical criteria determination to evaluate inflammatory activity after 6 months of treatment. We compared clinical criteria with PET capacity to determine IA. The results between the initial and final PET were finally compared. Results: Clinical criteria had a sensitivity of 63% and a specificity of 90% to show IA. Sensitivity decreased after 6 months of treatment to 27%. Discussion: This is the first prospective study that compares the findings of PET before and after treatment for IA in patients with TA. Clinical criteria lack sensitivity for the detection of IA in the follow-up after treatment. Conclusions: PET is a diagnostic technique with high sensitivity and specificity for the diagnosis and monitoring of patients with TA and inflammatory activity.