[Anaplastic carcinoma of the thyroid: long-term survival].

Anaplastic carcinoma of the thyroid is a highly aggressive neoplasm with quickly total course. It is characterized by an average survival of 4-12 months. It infiltrates precociously into the windpipe, oesophagus, vessels of the neck and gives distant metastases in 10-48% of cases. In 30.8 to 80% of cases, this carcinoma originates in an old multinodular goiter. The hypothesis has been also advanced that this neoplasm could derive from a pre-existent well-differentiated carcinoma. The improvement in diagnostic techniques (especially immunohistochemistry) allows a more correct definition of this neoplasm, permitting a differential diagnosis with other tumours (lymphoma, medullary carcinoma, hemangioblastoma) with which in the past it has been erroneously identified. The results reported in the literature are controversial as regards long-term survival, but usually it is less than one year. Longer survival must lead to the suspicion of wrong diagnosis. A relatively better prognosis is observable in intraglandular forms, "minimi" neoplastic focus and young patients. The presence of regional metastatic lymph nodes doesn't seem to modify the prognosis. Instead, a factor which can condition the prognosis is the type of therapy. Now a days the most efficacious curative treatment is the multinodal one (surgery, radio- and chemotherapy). The best results about survival and quality of life have been obtained using chemo-radiotherapy before operation and chemotherapy after it.