The “discovery” analysis set included five PGL tumor samples, all belonging to the Cluster 1 representing PPGLs with highest risk of metastasis, multiplicity, or recurrence (patients 1, 2, and 3 harboring germline SDHB mutations and patients 13 and 14, both with a germline VHL mutation (Table 1, detailed information is provided in Table S1)). This evidence concerns the gene SDHB and neoplasm.