25244              ADENOMA OF THYROID

This patient was a woman aged 76 who died of congestive cardiac failure secondary to myocardial infarction.  There was a previous history of an operation for goitre.

The specimen consists of the larynx, trachea and thyroid gland viewed from behind to show the left lobe of the thyroid replaced by a yellow spheroidal adenoma measuring 3.5 cms in length.  Its cut surface shows many areas of necrosis and there is a thick fibrous capsule.  No normal thyroid tissue is present in this lobe.  The right lobe is small and atrophic.  Histology shows a micro-follicular adenoma in which a thin rind of small follicles is present beneath the dense fibrous capsule.  The bulk of the nodule is dense eosinophilic hyaline stromal material containing many calcified areas.  Follicular epithelium in this hyaline matrix is very irregular and atrophic.  Often only one or two epithelial cells remain in the follicular cavity.  There is no intrafollicular colloid.  The Congo Red stain for amyloid is negative.