Just had a breast ultrasound and it says 3cm fn. what does the fn stand for. i will be following up with my doc but can't get in until next week. ta?

Fibroadenoma.: It stands for fibroadenoma, a relatively common benign breast nodule. Ultrasound cannot really make a definitive histologic diagnosis(that would require biopsy), but if all of the sonographic features are present, ultrasound can predict it with a high degree of probability. This could be followed up at 6 month intervals, or undergo needle biopsy if a more immediate diagnosis is desired.