pheochromocytoma (PHEO) and paraganglioma (PGL), collectively referred to as PPGL, originate from the neural crest cells of the embryonic ectoderm and are a rare but non-rare class of neuroendocrine tumors (NET). About 40% of PPGL manifests as a genetic syndrome involving at least 24 characteristic germline mutation pathogenic driver genes［1, 2, 3, 4, 5, 6, 7, 8, 9, 10］。 In recent years, the relevant guidelines and expert consensus of PPGL recommend that all PPGL patients should be subjected to germline-level genetic testing and molecular typing. Priority is given to target gene set sequence capture sequencing based on second-generation sequencing technology, and then individualized and precise management can be implemented［1, 2, 3, 4, 5, 6, 7, 8, 9］。 Although associated with MYC-associated factor X,MAXPPGL syndrome associated with germline mutations of the) gene (online Human Mendelian Inheritance code 154950) has been reported one after another［11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23］However, its clinical characteristics are not exhaustive and rarely reported in China. We retrospectively analyzed the clinical diagnosis and treatment data of 2 patients with PHEO from 2 familiesMAXGermline mutation types, combined with a family survey and literature review, are reported below.
