Differentiated thyroid cancer (papillary). Brain tumor metastasis as clinical onset. surgical treatment and ¹³¹I. 8 years disease-free

Introduction: The differentiated thyroid cancer is the most common endocrine neoplasia. The major manifestation belongs to the papillary variant (65-90%). The prognosis tends to be very favorable, with a mortality rate of 1.8 % and a disease-free rate up to 10 years of around 90-95 %. The distant metastasis in brain accounts for 0.1-5 %. There are no established protocols for the management of brain metastasis. Therapeutic options are: surgery, stereotactic radiotherapy / radiosurgery, and ¹³¹I. The successful management of this case is an option for brain metastasis from thyroid papillary carcinoma. Case report: A 77 year-old female begins with double vision (diplopia). She underwent twice a surgery for brain tumor with a histopathological report on thyroid papillary tissue. The endocrine evaluation determines euthyroid state except thyroglobulin (TG) 2300 ng/ml. Total thyroidectomy with classic thyroid papillary carcinoma. A diagnostic ¹³¹I scan after surgery shows for first time brain metastasis uptake. The patient receives 25 mCi of ¹³¹I as initial therapeutic dose, and subsequent therapeutic doses (50, 50, 75, 75, 50 mCi) in 2 years, in accordance with the evolution of magnetic resonance, clinic, endocrine lab, hematological analysis, and ¹³¹I scintigraphy, that shows the possible remission of the disease. The follow-up was carried out by means of a clinical control, thyroglobulin values, U.S., ¹³¹I scans, and magnetic resonance. The patient is at the present time over 11 years survival and 8 years disease-free. Discussion: Even though the distant metastasis is not very common in brain and is generally associated with aggressive variants of tumor, our case started with a metastatic brain tumor in an euthyroid patient with no thyroid pathology background and with low-risk post-thyroidectomy criterion. The ¹³¹I scan turned positive in brain metastasis when the patient was thyroidectomized. This detail must be considered important, since it makes it possible to understand the behavior of the metastatic lesions when the primary thyroid tissue is present or absent. Conclusion: We presented a case involving a patient with brain metastasis from thyroid papillary carcinoma. The management of this disease was: previous surgeries to improve the initial neurological clinic, thyroidectomy, and ¹³¹I with therapeutic doses in stages and in a fractional manner with an initial therapeutic dose of 25 mCi, and an accumulated ¹³¹I dose of 325 mCi. (authors)