Thyroid cancers are mainly papillary, follicular, medullary or anaplastic thyroid cancer. Malignant anaplastic meningioma is an especially malignant tumor with aggressive behavior. Fewer than 10% form more slowly following degeneration of low-grade astrocytoma or anaplastic astrocytoma. CD30 is associated with anaplastic large cell lymphoma. Other mimics include CD30 positive B-cell lymphomas with anaplastic cells (including Hodgkin lymphomas). Thyroglobulin is not produced by medullary or anaplastic thyroid carcinoma. This protein is involved in cancers when spliced with the anaplastic lymphoma kinase. Ceritinib is a selective and potent inhibitor of anaplastic lymphoma kinase (ALK). In poorly differentiated forms, malignant epithelial cells are discohesive, pleomorphic, anaplastic, and giant. ALK was first identified as a chromosomal rearrangement in anaplastic large cell lymphoma (ALCL). Blood spread is also possible in thyroid cancers, especially in follicular and anaplastic carcinoma. The 2;5 chromosomal translocation is associated with approximately 60% anaplastic large-cell lymphomas (ALCLs). Tumor cells are very pleomorphic (anaplastic), some are giant, numerous atypical mitoses. There are a number of clinical trials for anaplastic thyroid carcinoma underway or being planned. Patients with medullary, anaplastic, and most Hurthle cell cancers do not benefit from this therapy.