[Etiological analysis of a patient with multiple primary malignant neoplasms]

To investigate the etiology of multiple primary malignant neoplasms occurred in one patient. Retrospective analysis was performed on a 52-year-old female patient who was admitted to the Department of Endocrinology, the First Affiliated Hospital of Sun Yat-Sen University on October 7, 2021, due to "thyroid occupying lesion for one week". A complete systemic positron emission tomography examination of the patient indicated that the metabolic characteristics of the left thyroid nodules were consistent with medullary thyroid carcinoma, those of the right thyroid nodules were consistent with papillary thyroid carcinoma, and the metabolic characteristics of the T_6-7 level were consistent with meningioma, and teratoma was found in the right ovarian region. Intradural subdural mass resection was performed on October 20, 2021, and bilateral total thyroidectomy, isthmus thyroidectomy, bilateral central lymph node dissection and left cervical lymph node dissection were performed on November 2, 2021. The postoperative pathologic diagnosises were meningioma (WHO Grade 1), medullary thyroid carcinoma (left side), and papillary thyroid carcinoma (right side).Whole exon gene sequencing revealed the presence of mutations in the ACAN and FLNB genes, which are associated with dysplasia, as well as mutations in the DDX41 and JAK2 genes, which are linked to active pro-proliferation signaling and tumor susceptibility. In this study, a gene mutation pattern which could lead to multiple primary malignant neoplasms was found.