Worldwide, the incidence of thyroid cancer has greatly increased in the last decades with female 
predominance. Increase in incidence of more advanced disease has also been reported. Poorly 
differentiated thyroid cancer is a rare aggressive subtype of thyroid cancer that does not appear denovo from the start, it starts as differentiated cancer then dedifferentiation occurs by genetic factors. It 
is the main cause of death from non-anaplastic follicular cell derived thyroid cancer. It expresses 
thyroglobulin, as differentiated thyroid cancers and usually does not concentrate radioactive iodine 
with increased glucose transporter 1 expression, like anaplastic thyroid cancers. This type of cancer 
has high risk of local recurrence and distant metastasis. Management of this type of cancer is 
challenging with overall poor therapy response and prognosis with high mortality rate when compared 
to differentiated thyroid cancers. Surgery is the standard management in early operable cases followed 
by radioactive iodine therapy (after testing avidity)/radiotherapy/chemotherapy and the recently 
available molecular targeted therapies are promising.