and importance: Papillary Thyroid carcinoma (PTC) is the most common endocrine malignancy and accounts for 1-2% of all cancer cases. Second malignancies in women diagnosed with thyroid cancer are of concern given the young average age at diagnosis. The concurrent occurrence of thyroid cancer and malignant brain tumor such as glioblastoma (GBM) was rarely seen and reported. However, the simultaneous association of these 2 conditions, namely PTC and GBM, in a neurofibromatosis type 1 (NF1) patient, has never been reported before in the literature. The authors report the first case of an extremely rare association combining papillary thyroid carcinoma, glioblastoma, and a neurofibromatosis 1 in a 34-year-old female patient with primary generalized tonic-clonic seizures. NF1 can be associated with PTC and GBM independently. In this current case, NF1 was accompanied by both PTC and GBM. With the exception of the present case, to our knowledge, there has been no previous case report in the literature in which these 3 entities were associated. The reason for the rarity of this combination of these neoplasms in patients with NF1 remains not clear, but it may be explained by the low incidence of combined occurrence of PTC and GBM. This is the first reported extremely rare coexistence of GBM and PTC in a female NF1 patient. Further genetic investigations could improve our understanding of this combination and change our therapeutic approaches.