Utilidad de la elastografía cuantitativa por ultrasonografía endoscópica (USE) para el diagnóstico de las lesiones sólidas del páncreas (LSP) / Utility of quantitative elastography by Endoscopic Ultrasound (EUS) to diagnose solid pancreatic lesions (SPL)

Resumen Introducción: la punción con aguja fina guiada por ultrasonografía endoscópica (PAF-USE) permite un diagnóstico de las lesiones sólidas del páncreas (LSP) con una sensibilidad de alrededor del 85 % en la literatura mundial y aún más baja en nuestro medio, por lo cual se requiere explorar nuevos accesorios (agujas) o técnicas tales como la elastografía, que mejoren esta sensibilidad. Esta última permite la cuantificación de la rigidez del tejido con altos grados de precisión y desde 2001 se ha aplicado al diagnóstico de tumores sólidos de diversos órganos como mama y tiroides, músculo, entre otros; y desde 2006 se ha empleado para las LSP y ha demostrado su utilidad como complemento a las herramientas diagnósticas disponibles, ya que mejora la precisión de la biopsia por PAF-USE al seleccionar el área más sospechosa para ser puncionada y también guía el manejo clínico cuando la PAF-USE es negativa o no concluyente. Objetivo: evaluar el rendimiento diagnóstico de la elastografía cuantitativa de strain ratio (SR) obtenida por ecoendoscopia en las LSP teniendo como patrón de oro el diagnóstico citopatológico. Métodos: 71 pacientes (rango de edad: 35-89, media: 62,2 años); de estos, 35 mujeres fueron sometidas a USE para la evaluación de LSP. El diseño del estudio fue de corte transversal, prospectivo y de un solo centro. La USE se realizó con un ecoendoscopio Pentax lineal y un procesador Hitachi-Noblus. La lesión (área A) y un área de referencia B se seleccionaron para calcular la relación de deformación (B/A, SR expresada en %). Se tomó como punto de corte SR para definir las lesiones malignas (duras) SR > 22 teniendo en cuenta la evidencia actualmente disponible; estos resultados se compararon con la citopatología de las muestras obtenidas por punción guiada por USE. Después de la aplicación de criterios de exclusión, se realiza el análisis estadístico de 56 pacientes y se considera el valor p < 0,05. Se calculó la sensibilidad, especificidad, valor predictivo positivo (VPP), valor predictivo negativo (VPN) y precisión diagnóstica comparando la elastografía SR con los diagnósticos finales por citopatología. Resultados: la elastografía cuantitativa SR (%) permite detectar las LSP malignas con sensibilidad del 94,6 % (intervalo de confianza [IC] del 95 %: 85,4 %-98,2 %), especificidad del 89,3 % (IC 95 %: 78,5 %-95,0 %), VPP del 89,8 % (IC 95 %: 79,5 %-95,3 %); VPN del 94,3 % (IC 95 %: 84,6 %-98,1 %) y exactitud del 92,0 % (IC 95 %: 85,4 %-95,7 %). Conclusión: la elastografía cuantitativa SR por USE en LSP es un complemento útil que mejora la precisión de la PAF-USE al seleccionar el área más sospechosa para ser puncionada y guiar el manejo clínico cuando la PAF-USE es negativa o no concluyente, ya que tiene una alta sensibilidad y especificad en el diagnóstico de las LSP malignas.

Abstract Introduction: Endoscopic ultrasonography with fine-needle aspiration allows performing a diagnosis of solid pancreatic lesions with an approximate 85% sensitivity, as referenced in specialized literature, and even lower sensitivity as per local research. To yield better sensitivity and to improve the results, it is required to examine new elements (needles) and techniques like elastography. Elastography helps in the quantification of tissue stiffness with a high level of accuracy. Since 2001, elastography has been applied in diagnosing solid forms of cancer (tumors) that affect organs like breasts, the thyroid, and some muscles. This method which has been used to diagnose solid pancreatic lesions (SPL) since 2006 has proved to be useful as a complementary method to the existing diagnostic techniques. It improves the accuracy of the endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNA) by selecting the more suspicious area to be punctured, and it also guides the clinical treatment after getting a negative EUS-FNA or a non-conclusive result. Objective: To evaluate the diagnostical performance of the strain ratio (SR) quantitative elastography by ecoendoscopy in solid pancreatic lesions, considering the cytopathologic diagnostic as the gold standard. Methods: 71 patients (age range: 35-89 years old, mean: 62.2 years old); out of those 71 patients, The EUS to diagnose SPL, was performed on 35 women. This was a single-center, prospective cross-sectional study design. The EUS was performed with a Pentax linear endoscope and a Hitachi-Noblus ultrasound. The lesion (area A) and a reference area B were selected to calculate the deformation ratio (B/A, SR expressed as a percentage). SR > 22 was selected as a cut-off point to determine the malignant lesions (solid lesions), considering the evidence currently available. The results were compared with their cytopathology interpretation once that the EUS was performed. After the exclusion criteria was applied, a statistical analysis of 56 patients was performed, considering p < 0,05. The sensitivity, the specificity, the positive predictive value (PPV), the negative predictive value (NPV) and the diagnostic accuracy, were calculated, comparing the elastography SR with the final diagnostics with the cytopathology interpretation. Results: Quantitative elastography SR (%) allows to detect the malignant SPL with sensitivity 94.6% (95% confidence interval [CI]: 85.4%-98.2%), specificity of 89.3% (CI 95%: 78,5 %-95,0 %), PPV of 89.8% (CI 95 %: 79,5 %-95,3 %); NPV of 94.3% (IC 95 %: 84,6 %-98,1 %) and an accuracy of 92.0% (CI 95 %: 85,4 %-95,7 %). Conclusion: SR quantitative elastography by Endoscopic Ultrasound, EUS is a suitable complement method that improves the EUS-FNA accuracy, by selecting the most suspicious area to be punctured, and it also guides clinical treatment after getting a negative EUS-FNA or a non-conclusive result, due to its high sensitivity and specificity levels to diagnose malignant SPL.

Diagnostic value of endoscopic ultrasound guided fine needle aspiration combined with the new category of papanicolaou society of cytopathology in solid pancreatic lesions / 中华消化杂志

Objective To study the diagnostic value of endoscopic ultrasound guided fine needle aspiration (EUS-FNA) combined with the new category of papanicolaou society of cytopathology in solid pancreatic lesions (SPL) rapid on-site evaluation (ROSE).Methods From February 2011 to October 2014,225 patients with SPL who underwent EUS-FNA and obtained the cytological diagnosis were enrolled.The lesions were finally diagnosed according to pathological results,imaging and follow-up data,and then the sensitivity,specificity,and accuracy of EUS-FNA in the diagnosis of SPL were calculated based on the new papanicolaou society of cytopathology terminology.Logistic stepwise regression analysis was performed to analyze the risk factors.Results Among 225 patients with SPL,96 cases (42.7％)had uncertain cytological diagnosis,17.3％ (39/225) could not be diagnosed,8.0％ (18/225) were atypical lesions,and 17.3％ (39/225) were suspicious malignant carcinomas.Among 129 cases (57.3％)with certain cytological diagnosis,15.1％ (34/225) were benign lesions,14.7％ (33/225) were tumors (benign or others) and 27.6％ (62/225) were malignant tumors.When atypical lesions were added into non-tumor lesions or tumor lesions,the sensitivity,specificity and accuracy of diagnosis were 87.3 ％,91.7％,88.2％,and 94.7％,72.2％,90.3％,respectively.Serum CA125≥14 kU/L (odds ratio (OR) =7.13,95％ confidence interval (CI) 2.02 to 25.22,P=0.002) and history of biliary disease (OR=3.85,95％CI 1.22 to 12.51,P=0.022) were two independent risk factors of pancreatic tumors.Conclusions Despite of a high percentage of uncertain cytological diagnosis,EUS-FNA still has high diagnostic value in SPL when combined with the new papanicolaou society of cytopathology terminology.Furthermore,serum CA125≥14 kU/L and history of biliary disease may help to diagnose pancreatic tumors.

Endoscopic ultrasound-guided needle-based confocal laser endomicroscopy for diagnosis of solid pancreatic lesions

An accurate diagnosis of solid pancreatic lesions (SPLs) is important because pancreatic cancer cannot be ignored if curative treatment is possible. Prompt and reliable diagnostic procedures are greatly needed for patients presenting with SPLs, particularly where resection is possible for a malignant mass. Several endoscopic ultrasound (EUS)-related technologies including a novel EUS-guided needle-based confocal laser endomicroscopy (EUS-nCLE) can provide real-time images at the cellular level (1,000-fold magnification). A 19-gauge EUS-guided fine needle aspiration (EUS-FNA) needle is recommended because its channel is large enough for the 0.85-mm diameter nCLE miniprobe. The procedure is performed by standard EUS-FNA techniques with either pre- or post-loading technique. Ten percent fluorescein sodium (2.5–5 mL) is used as an enhancing agent and is intravenously injected immediately before puncturing the lesion. Only a few studies have used the technique and reported results. A recent study from 19 malignant and 3 benign SPLs classified EUS-nCLE findings according to 4 signs: dark clumps, and dilated vessels (predominantly seen in malignant SPLs) and fine white fibrous bands and normal acini (predominantly seen in benign SPLs). Using these criteria, researchers correctly diagnosed 18 of the malignant SPLs (94.7%). Another study described 2 lesions as having “dark cells aggregates with pseudo-glandular aspects, and straight hyperdense elements more or less thick corresponding to tumoral fibrosis” in 17 of 18 malignant SPLs. Thus far, no large and systematic study has been performed to evaluate the potential clinical use of EUS-nCLE for diagnosing SPLs. However, based on available information from a few studies and the current limitations of EUS-FNA, EUS-nCLE can potentially provide a complementary role in diagnosing such lesions. Nevertheless, more studies are certainly needed.