Context: Pheochromocytomas and paragangliomas (PPGLs) are diagnosed earlier in patients with hereditary than sporadic disease. Whether other factors influence age at diagnosis is unclear. Objective: We examined ages at which PPGLs were diagnosed according to different catecholamine phenotypes and locations of tumors. Design & Setting: Retrospective multicenter study. Patients: Patients with PPGLs included 172 with and 183 without identified germline mutations or hereditary syndromes. Biochemical Measurements: Differences in plasma concentrations of metanephrine, a metabolite of epinephrine, were used to distinguish epinephrine-producing tumors from those lacking epinephrine production. Results: Patients with epinephrine-producing tumors were diagnosed 11 yr later (P < 0.001) than those with tumors lacking appreciable epinephrine production. Among patients without evidence of a hereditary condition, those with and without epinephrine-producing tumors had respective mean ± SE ages of 50 ± 2 and 42 ± 2 yr (P < 0.001) at diagnosis. Patients with multiple endocrine neoplasia type 2 and neurofibromatosis type 1, all with epinephrine-producing tumors, were similarly diagnosed with disease at a later age than patients with tumors that lacked appreciable epinephrine production secondary to mutations of von Hippel-Lindau and succinate dehydrogenase genes (40 ± 2 vs. 31 ± 1 yr, P<0.001).Amongthe latter patients, those with multifocal tumors were diagnosed earlier than those with solitary tumors (19 ± 3 vs. 34 ± 2 yr, P < 0.001). Conclusions: The variations in ages at diagnosis associated with different tumor catecholamine phenotypes and locations suggest origins of PPGLs from different chromaffin progenitor cells with variable susceptibility to disease causing mutations. Different optimal age cut-offs for mutation testing are indicated for patients with and without epinephrine-producing tumors (44-49 vs. 30-35 yr, respectively).