January - March 2009, Volume 5, Issue 1

Botusan IR, Terzea D, Constantin I, Ioachim D, Stanescu B, Enachescu C, Barbu C, Fica SV

Rare evolution of a papillary thyroid carcinoma dedifferentiated to an anaplastic form with rhabdoid features - case presentation

Acta Endo (Buc) 2009, 5 (1): 99-106
doi: 10.4183/aeb.2009.99

Anaplastic thyroid carcinoma (ATC) is the most aggressive type of thyroid\r\ndedifferentiation. Rarely, ATC associates rhabdoid characteristics and only few cases have been\r\npresented to date. We present a case of a thyroid papillary carcinoma which shifted to an\r\naggressive anaplastic form with rhabdoid dedifferentiation and concomitant leukemic reaction\r\nwith eosinophilia. A 76 years old man with a long standing history of a thyroid nodule, noticed\r\nwithin months a rapid growth of the nodule associating marked compression phenomena with\r\nleft deviation of the trachea and esophagus and mild dysphonia. Palliative surgery was\r\nperformed, but the evolution was unfortunate with further health deterioration (fatigue, dyspnea,\r\ndysphagia, loss of appetite and weight loss). Laboratory tests proved leukocytosis with\r\nneutrophilia and left deviation of leukocytes formula, with major eosinophilia. The pathology\r\nshowed a thyroid papillary carcinoma with anaplastic changes. By immunohistochemistry,\r\nit was confirmed the thyroid origin of the tumor (thyreoglobulin positive areas) but also the\r\nepithelial nature of the undifferentiated areas (positive areas for cytokeratin and epithelial\r\nmembrane antigen). Moreover, in the anaplastic areas, rhabdoid differentiation was\r\nidentified by positive coloration against vimentin, protein S100 and desmin. The tumor was\r\naggressive by its anaplastic transformation, confirmed by a high proliferation index (Ki67:\r\n40% positive). The computed tomography was concordant with the phenotype predicted by\r\nhistological description showing a malignant thyroid tumor, invading cervical and mediastinal\r\nareas with secondary lung disseminations. Unfortunately, the outcome was fatal even though\r\nadditional treatment methods have been tried: radiotherapy and chemotherapy. The\r\nparticularities of this case reside in the very rare dedifferentiation of a papillary thyroid\r\ncarcinoma towards an anaplastic thyroid carcinoma harboring the rhabdoid phenotype and\r\nalso its association with eosinophilia.

Keywords: anaplastic thyroid carcinoma; rhabdoid dedifferentiation; eosinophilia.

Correspondence: Simona. Fica, MD, Department of Endocrinology, Elias Hospital, Bucharest,\r\nemail: simonafica@yahoo.com, fax: +40 21 314 14 00