ATC commonly causes symptoms by compressing local structures, such as the esophagus, carotid arteries, recurrent laryngeal nerve and trachea.

[2] Risk factors include being over the age of sixty, a long-standing goiter, and repeated radiation exposure to the chest or neck.

This suggests that many ATC cases have dedifferentiated from differentiated thyroid cancer and, as a result, become more aggressive and difficult to treat.

[2] The presence of regionally swollen lymph nodes in older patients in whom needle aspiration biopsy reveals characteristic vesicular appearance of the nuclei supports a diagnosis of anaplastic carcinoma.

[2] On immunohistochemistry testing, ATC is usually positive for the keratin, p53, and PAX8 proteins and is negative for thyroid transcription factor-1, thyroglobulin, and calcitonin.

[2] The presence of PAX-8 positive staining and association with a different thyroid cancer that is adjacent to the ATC support the diagnosis.

[2] ATC is considered an emergency cancer diagnosis since it poses a high risk of blocking the airway and/or esophagus due to its rapid growth in the neck, either of which can quickly cause a person's death by asphyxiation, if not immediately corrected.

[2] Medications, such as fosbretabulin (a type of combretastatin), bortezomib and TNF-Related Apoptosis Induced Ligand (TRAIL), are, however, under investigation in vitro and in human clinical studies.

[9] With the advent of molecular testing and next-generation sequencing, BRAF and MEK inhibitors are playing an increasing role in the management of patients with anaplastic thyroid cancer harboring such mutations.

Immunotherapy is also starting to play an important role in anaplastic thyroid cancer management with several ongoing clinical trials demonstrating promising effects.

Combinatorial therapy that is molecular-based may lead to significant tumor regression, potentially making patients amenable to curative surgery.

The National Comprehensive Cancer Network Clinical Practice Guidelines currently recommend that postoperative radiation and chemotherapy be strongly considered.

[15] Additional factors that affect prognosis include the person's age, the presence of distant metastases, the dose of radiation administered to the primary tumor and regional lymph nodes, and if combined modality treatment is used.

[2] Treatment of anaplastic thyroid cancer is generally palliative in its intent due to its highly aggressive nature and nearly universal mortality.

Death is attributable to upper airway obstruction and suffocation in half of patients, and to a combination of complications of local and distant disease, or therapy, or both in the remainder.