A medium power view of a microfollicular adenoma (MGG). At this magnification lack of background colloid, uniformity of cells and microfollicular pattern are obvious. In the absence of nuclear atypia, crowding or papillary architecture these lesions are classified differently either as follicular lesion, cytologically benign, Thy3 or follicular lesion - indeterminate. In all cases the physician must know that criteria to predict a well differentiated follicular carcinoma are only histological following excision of the lesion to search for capsular or vascular invasion. However an aggressive surgical approach will result in many benign lesions being excised.