There is colloid in the background in both cases. The main differences between the two cases are as follows: the ratio of monolayered sheets to micro- and nomofollicles, the proportion of isolated nuclei and the degree of anisonucleosis is greater in non-neoplastic patient compared with those in patient with follicular adenoma.

The ultrasound presentations are also characteristics. The thyroid is composed of multiple nodules is the hyperplastic case while there is a solitary nodule presenting perinodular blood flow in the tumorous case. The presence of halo is doubtful in the follicular adenoma.