Poorly differentiated thyroid cancer

Poorly differentiated thyroid carcinoma is malignant neoplasm of follicular cell origin showing intermediate histopathological patterns between differentiated and undifferentiated thyroid cancers.

Histopathology

 * Presence of small cells with round nuclei and scant cytoplasm with a diffuse solid pattern
 * Round or oval nests (insulae) or in trabeculae.
 * Solid growth and presence of microfollicles, some of which contain dense colloid.
 * Extrathyroidal extension and blood vessel invasion
 * Foci of necrosis,
 * Larger than 5 cm in greatest diameter at diagnosis

Epidemiology

 * PDTC affects predominantly females about 55 years of age