In the multivariate Cox regression analysis, combining all histopathological and immunohistochemical features, SDHB loss, mitoses > 3/10 HPF, and larger tumor size (> 5.1 cm) were found to be associated with lower metastasis-free survival in PCC/PGL patients (Table 4). This evidence concerns the gene SDHB and adrenal gland pheochromocytoma.