Your ultrasound report is lacking details about the nodules such as blood flow, regular/irregular borders, present/absent calcification; mixed echogenicity most likely means complex cyst; hyperechoic lesion can be cystic.
Unfortunately, this is all the reports states. It was not a "nuclear" test just a regular ultrasound -- would it still state or show the things you mentioned?
If absent information means absent worrysome features, the biopsy still can be recommended for complex nodule. It suppose to be ultrasound-assisted, so the sample will be obtained from solid portion of the nodule.