Intrathyroideal papillary thyroid carcinoma presenting with a solitary brain metastasis

Papillary thyroid carcinoma (PTC) is the most common type of well-differentiated thyroid carcinoma and typically has an excellent prognosis. The incidence of distant metastasis from PTC is low. However, once metastasis has developed in a distant site, prognosis is markedly diminished. Brain metastases from PTC are extremely rare. No consensus regarding management has yet been reached. We report on the case of a patient who presented with signs of intracranial hypertension. Cranial magnetic resonance imaging (MRI) identified a lesion of the right temporofrontoparietal lobe. The patient underwent a craniotomy with a total removal of the tumor. Histologic examination of the lesion showed a metastasis of papillary adenocarcinoma. We observed a cold nodule in the right lobe of the thyroid on physical examination and imaging techniques (e.g., CT and scintigraphy). Fine-needle-aspiration cytology of the nodule was reported as PTC. A total thyroidectomy was performed and histopathological examination showed intrathyroidal variant of PTC. Postoperatively adjuvant whole brain radiation therapy with 44 Gy to multiple brain metastases of PTC was applied. One month later, the patient then underwent ¹³¹I radioiodine therapy with 150 mCi of ¹³¹I given orally. In conclusion, the present case underwent an aggressive multimodal approach therapy. This report indicates that the early detection and control of brain metastases may contribute to a better quality of life for patients affected by brain metastases.