Management of Papillary Thyroid Cancer Metastatic to the Central Nervous System: A Narrative Review of the Literature

Brain metastases (BM) associated with papillary thyroid cancer (PTC) occur with an approximate frequency of 0.15% to 1.3% of PTC cases. There is little evidence regarding the treatment of this association (PTC and BM). A narrative review of the literature is presented. We assessed multiple treatment options and its effectiveness in this vulnerable population. Methods: The data were collected using the PubMed search engine and Google Scholar. There were selected all studies that included: << thyroid carcinoma >> << brain metastases >> << radiotherapy >> << surgery >> << iodine-131 >> << papillary carcinoma >> << differentiated carcinoma >>. Once the relevant works had been listed and compared, the main findings of each one were related and analyzed. Results: We found 15 studies between the years 1990 and 2019 that describe 187 patients with thyroid cancer and brain metastases; of which 138 presented PTC, and 62% (58/93) were women. The average age was 59 years. Patients who received multimodal treatment (association of 2 or more therapies; one of them, brain metastasis resection) had a longer survival, with an average of 54 months, compared to monotherapy. Discussion: Patients with PTC who also present BM require a multimodal therapy approach: when it is associated with brain metastasis resection, better results are evident; in contrast, when monotherapy is used, a limited performance is observed, with poor results. Conclusion: Patients with PTC who also present BM have better outcomes and higher survival rate with a multimodal therapy approach, including brain metastasis resection.