Accuracy of sonography and hysteroscopy in the diagnosis of premalignant and malignant polyps in postmenopausal women

Abstract

PURPOSE: To evaluate the accuracy of sonographic endometrial thickness and hysteroscopic characteristics in predicting malignancy in postmenopausal women undergoing surgical resection of endometrial polyps. METHODS: Five hundred twenty-one (521) postmenopausal women undergoing hysteroscopic resection of endometrial polyps between January 1998 and December 2008 were studied. For each value of sonographic endometrial thickness and polyp size on hysteroscopy, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated in relation to the histologic diagnosis of malignancy. The best values of sensitivity and specificity for the diagnosis of malignancy were determined by the Receiver Operating Characteristic (ROC) curve. RESULTS: Histologic diagnosis identified the presence of premalignancy or malignancy in 4.1% of cases. Sonographic measurement revealed a greater endometrial thickness in cases of malignant polyps when compared to benign and premalignant polyps. On surgical hysteroscopy, malignant endometrial polyps were also larger. An endometrial thickness of 13 mm showed a sensitivity of 69.6%, specificity of 68.5%, PPV of 9.3%, and NPV of 98% in predicting malignancy in endometrial polyps. Polyp measurement by hysteroscopy showed that for polyps 30 mm in size, the sensitivity was 47.8%, specificity was 66.1%, PPV was 6.1%, and NPV was 96.5% for predicting cancer. CONCLUSIONS: Sonographic endometrial thickness showed a higher level of accuracy than hysteroscopic measurement in predicting malignancy in endometrial polyps. Despite this, both techniques showed low accuracy for predicting malignancy in endometrial polyps in postmenopausal women. In suspected cases, histologic evaluation is necessary to exclude malignancy. ResumoOBJETIVO: Avaliar a acurácia da espessura endometrial ecográfica e características histeroscópicas em predizer malignidade em mulheres na pós-menopausa submetidas à ressecção cirúrgica de pólipos endometriais. MÉTODOS: Quinhentos e vinte e uma (521) mulheres na pós-menopausa submetidas à ressecção histeroscópica de pólipo endometrial entre janeiro de 1998 e dezembro de 2008 foram incluídas no estudo. Para cada valor de espessura endometrial ecográfica e tamanho dos pólipos na histeroscopia, a sensibilidade, a especificidade, valor preditivo positivo (VPP) e valor preditivo negativo (VPN) foram calculados em relação ao diagnóstico histológico de malignidade. Os melhores valores de sensibilidade e especificidade para o diagnóstico de malignidade foram determinados pela curva Receiver Operating Characteristic (ROC). RESULTADOS: O diagnóstico histológico identificou a presença de pré-malignidade ou malignidade em 4,1% dos casos. A espessura endometrial medida por ultrassonografia em casos de pólipos malignos foi maior quando comparado com pólipos benignos e pré-malignos. Na histeroscopia os pólipos malignos também foram maiores. A espessura endometrial de 13 mm mostrou uma sensibilidade de 69,6%, especificidade de 68,5%, VPP de 9,3% e VP...