Diagnostic Value and Best Cut-off Point of Sonographic Parameters in Distinction between Benign and Malignant Superficial Lymphadenopathy

Background: Diagnosis of malignant lymphadenopathy is particularly important for treatment planning, staging before treatment and also for determination of prognosis. Various diagnostic procedures which are expensive and invasive are now used for distinguishing malignant from benign lymphadenopathies. Ultrasound has been proposed as a non- invasive, cost effective and available procedure compared with other procedures. This study was conducted to evaluate some ultra sound parameters in distinction between malignant and benign superficial lymphadenopathies. Methods: Lymph nodes of 100 patients who were candidates for pathological evaluation of their superficial lymphadenopathy were evaluated sonographically. The most accessible lymph nodes were marked and then biopsied and sonographic results were compared with pathologic ones, and the sensitivity and specificity of the test and the appropriate cut off point was determined based on the ROC curve and by SPSS 17. Results: Of 100 evaluated nodes 55 nodes were benign and 45 nodes were malignant. The ratio of cortical thickness to medullary thickness was not significantly different between malignant and benign lymph nodes. There was a significant difference between blood supply pattern and average indices of PI (P=.007) and RI (P<.001) between benign and malignant lymph nodes. The best cutoff point of cortex thickness to differentiate malignant from benign lymphadenopathy with 62.2٪ sensitivity and 72.7٪ specificity and 70٪ accuracy was 7.95 mm. Conclusion: The color Doppler criteria in combination with gray scale sonography can be very helpful in choosing patients for biopsy or FNA, but cannot fully replace pathological evaluation. Keywords: Color Doppler, Pathology, Superficial lymphadenopathy, Ultrasoun