When the needle is moved in different directions, it samples a much wider area than a core biopsy (FNA is thus more representative than a core biopsy). The to and fro movements and changing the direction of the needle, while it is still inside the lesion are the two crucial steps in procuring an adequate representative sample. Movement of the needle is adjusted according to the type of lesion. A sclerotic lesion will require more force than a soft tumor. A cyst will almost aspirate by itself. When fluid is aspirated, its color, consistency and amount should be recorded in the requisition form, which allows the lesion.
