Two of 5 lesions less than 2 cm(40.0%),14 of 93 lesions 2 to 4 cm(15.0%)and 4 of 88 lesions greater than 4 cm(4.5%)were benign lesions.

• 186例中肿瘤直径<2cm者5例；其中2例为良性病变(40%25)；肿瘤直径2-4cm者93例中14例为良性病变(15.；0%25)；肿瘤直径>4cm的88例中只有4例(4