Rendimiento del sistema Bethesda en el diagnóstico citopatológico del nódulo tiroideo / Efficiency of the Bethesda System for Thyroid Cytopathology

INTRODUCCIÓN: La punción-aspiración con aguja fina es una pieza clave en la evaluación preoperatoria del nódulo tiroideo y el sistema Bethesda es el más aceptado para categorizar el análisis citológico. El objetivo del estudio es evaluar la validez del sistema Bethesda en la enfermedad nodular tiroidea para diagnosticar malignidad. MÉTODOS: Se incluye a los pacientes intervenidos de tiroides consecutivamente entre junio de 2010 y junio de 2017. Se realizó el análisis de la punción preoperatoria según el sistema Bethesda, correlacionando este dato con la histología definitiva para cada nódulo biopsiado. Los parámetros de prueba diagnóstica se calcularon como prueba de screening (verdadero positivo: categorías IV, V, VI) y como método para identificar malignidad (verdadero positivo: categorías V, VI). RESULTADOS: Se incluyó a 522 pacientes, de los que 184 (35,2%) presentaron un carcinoma en la histología definitiva; siendo el carcinoma papilar el más frecuente (84,2%). Los porcentajes de malignidad en el nódulo biopsiado para cada categoría Bethesda fueron: I, 0%; II, 1,5%; III, 6,4%; IV, 31%; V, 86,5% y VI, 100%. En el análisis como prueba de screening, se identificó una sensibilidad del 98,9%, especificidad del 84,4%, valor predictivo positivo del 69,6%, valor predictivo negativo del 99,5% y precisión diagnóstica global del 88,2%. En el análisis para detectar malignidad, los parámetros fueron: sensibilidad 98,6%, especificidad 97,6%, valor predictivo positivo 93,5%, valor predictivo negativo 99,5% y precisión diagnóstica global 97,9%. CONCLUSIONES: El sistema Bethesda es un método sencillo y reproducible en la categorización citológica del nódulo tiroideo, una herramienta útil en el manejo y eficaz para identificar el riesgo de malignidad

INTRODUCTION: To establish quality standards in oncologic surgery is a complex but necessary challenge to improve surgical outcomes. Unlike other tumors, there are no well-defined quality standards in pancreatic cancer. The aim of this study is to identify quality indicators in pancreatic oncologic surgery in Spain as well as their acceptable limits of variability. METHODS: Quality indicators were selected based on clinical practice guidelines, consensus conferences, reviews and national publications on oncologic pancreatic surgery between the years 2000 and 2016. Variability margins for each indicator have been determined by statistical process control techniques and graphically represented with the 99.8 and 95% confidence intervals above and below the weighted average according to sample size. RESULTS: The following indicators have been determined with their weighted average and acceptable quality limits: resectability rate 71% (> 58%), morbidity 58% (< 73%), mortality 4% (< 10%), biliary leak 6% (< 14%), pancreatic fistula rate 18% (< 29%), hemorrhage 11% (< 21%), reoperation rate 11% (< 20%) and mean hospital stay (< 21 days). CONCLUSIONS: To date, few related series have been published, and they present important methodological limitations. Among the selected indicators, the morbidity and mortality quality limits have come out higher than those obtained in international standards. It is necessary for Spanish pancreatic surgeons to adopt homogeneous criteria regarding indicators and their definitions to allow for the comparison of their results

Efficiency of the Bethesda System for Thyroid Cytopathology. / Rendimiento del sistema Bethesda en el diagnóstico citopatológico del nódulo tiroideo.

INTRODUCTION: Fine-needle aspiration biopsies are a key tool for preoperative assessment of thyroid nodules, and the Bethesda system is the preferred method to report cytological analysis. The purpose of this study is to assess the efficiency of the Bethesda system to identify the malignancy risk of thyroid nodules. METHODS: Patients who underwent thyroid surgery between June 2010 and June 2017 were included. Samples were classified into 6categories according to rates of malignancy associated with each diagnostic category. In order to investigate the correlation between categories, a statistical analysis compared the categories with pathology reports. Diagnostic indicators were calculated as a screening test (categories IV, V, VI as true-positive) and as a method to identify malignancy (V, VI as true-positive). RESULTS: In a series of 522 patients, we found 184 (35.2%) malignant tumours, papillary carcinoma being the most prevalent with 155 cases (84.2%). Malignant rates for diagnostic categories were: I, 0%; II, 1.5%; III, 6.4%; IV, 31%; V, 86.5%; VI, 100%. A robust correlation was identified between categories on statistical analysis. For the «screening test¼ analysis, sensitivity was 98.9%, specificity 84.4%, positive predictive value 69.6%, negative predictive value 99.5%, and diagnostic accuracy 88.2%. Analysing the accuracy to detect malignancy, values were: sensitivity 98.6%, specificity 97.6%, positive predictive value 93.5%, negative predictive value 99.5%, diagnostic accuracy 97.9%. CONCLUSION: The Bethesda system is a clear and reliable approach to report thyroid cytology and therefore is an effective tool to identify malignancy risk and guide clinical management.