Colloid nodule

[4] Colloid nodules are usually small enough to be undetectable without an ultrasound or other imaging techniques.

[5] They usually produce no symptoms, so patients are unlikely to notice them until their size makes them easier to detect.

Like other thyroid nodules, they are usually first noticed in a routine physical examination.

Follow-up examinations typically include an ultrasound if it is unclear whether or not there really is a nodule present.

Colloid nodules are not surrounded by a fibrous capsule of compressed tissue.

Histopathology of a colloid nodule of the thyroid, showing dilated thyroid follicles. There is some reactive fibrosis (at right) but no consistent capsule.