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 de-novo 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.