MON-311 A Multidisciplinary Strategy for Managing Complex MAX Gene Mutation in Endocrine Oncology

Abstract Disclosure: R. Adupa: None. D.X. Ramos Padilla: None. D. Suravajjala: None. R.V. Chemitiganti: None. Background: Germline mutations in the MAX (MYC-associated factor X) gene are increasingly recognized in hereditary pheochromocytoma and paraganglioma syndromes, as well as other tumors like pancreatic neuroendocrine tumors (PanNETs) (1). The MAX gene acts as a tumor suppressor by regulating the MYC-MAX-MXD1 network, responsible for cell differentiation, growth, and apoptosis. Mutations in this gene disrupt these processes, leading to the development of various tumors, including pheochromocytomas, paragangliomas, PanNETs, and non-endocrine tumors such as chondrosarcomas and lung adenocarcinomas. Genetic testing plays a crucial role in identifying these mutations, facilitating early detection and personalized management strategies. Clinical Case: A 58-year-old woman presented with several endocrine and cancer-related conditions. At age 35, she had bilateral adrenalectomy due to pheochromocytomas, resulting in adrenal insufficiency. She also underwent total thyroidectomy at age 33 for benign thyroid nodules, leading to hypothyroidism. At age 55, she was diagnosed with PanNET and required a Whipple procedure. Genetic testing at the time of Whipple’s procedure revealed a germline mutation in the MAX gene, explaining her predisposition to endocrine tumors. The patient’s family history was unremarkable. Her medications include hydrocortisone, Florinef, Levothyroxine, and lanreotide. This case highlights the importance of genetic testing in managing complex, endocrine-related conditions. Conclusion: This case demonstrates the significant challenges posed by a MAX gene mutation, which predisposes individuals to endocrine and other tumors. The patient’s complex history, involving multiple surgeries and hormone therapies, underscores the need for a multidisciplinary approach. Management includes endocrine replacement therapy, somatostatin analogues like lanreotide for their anti-proliferative effect, and regular surveillance, including biochemical tests and imaging. Prognosis varies based on tumor progression, and ongoing vigilance is crucial. Genetic testing remains essential for diagnosis, optimizing care, and understanding genotype-phenotype correlations. A comprehensive approach ensures better outcomes for patients with MAX gene mutations. Reference: (1) Turin CG, Crenshaw MM, Fishbein L. Pheochromocytoma and paraganglioma: germline genetics and hereditary syndromes. Endocr Oncol. 2022 Jun 28;2(1):R65-R77. Presentation: Monday, July 14, 2025