[Anaplastic transformation of papillary carcinoma of the thyroid]

Anaplastic transformation of well-differentiated carcinomas of the thyroid is not common. The authors present a case of a 61-year-old woman, on whom, 17 years earlier, a near-total thyroidectomy was performed with a unilateral selective lymphatic dissection of the neck because of a papillary carcinoma of the thyroid. The operations were followed by a course of external irradiation. For 17 years the patient had no complaints, then she was treated again for recurrence of tumor in the residual thyroid tissue. By biopsy next to papillary carcinoma the authors diagnosed an anaplastic tumor with giant cells, which led to the patient's death 6 months after the operation. Surveying the data in literature they draw attention to the role of external irradiation in anaplastic transformations after the first operation.