<qa>  What is the advantage of a selective LN aspiration based on LN characteristicsCharacteristics of benign and malignant LNs using ultrasonography have been described in various contexts. Cervical and axillary LNs provided accurate characteristics eg. shape, short- to long-axis ratio, number of blood vessels in LN, vascularization pattern, etc. in predicting malignancy with linear superficial transducers.7-11 LN characteristics using EUS or EBUS also have established criteria predicting mediastinal LN malignancy eg. size, shape, borders and echogenicity.12 Depending on the studies, it has been suggested to obtain specimens of all accessible LNs without considering their characteristics. It has also been suggested to proceed to a selective LN aspiration based on LN characteristics, with the advantage of cost reduction fewer needles used, less time to carry out procedure, and specimens needed to be analysed.6 