Thyroid lesions showing multitudes of small cysts are always benign follicular lesions. This patient insisted on FNA due to a positive family history. In a series of 1100  biopsy proven thyroid FNAs at our institution, not one lesion showing this appearance was positive for malignancy.

Lesions that are clearly defined with no microcalcifications and a clear interface between the lesion and the parenchyma ("halo") can be followed up safely with ultrasound. generally, lesions that enlarge should be sampled.

Thyroid lesions are best appreciated and evaluated in real-time ultrasound. Especially, the loss of border definition can be limited to a certain part of the lesion and does not necessarily appear on the static images. In this respect, thyroid and breast ultrasound are similar: real-time review is indicated in complex lesions.