SDHB and metastatic neoplasm: Although some features, including larger tumor size (especially more than 5 cm), extra-adrenal primary tumor site, younger age at diagnosis, or elevated levels of plasma 3-methoxytyramine (3-MT) [1] could guide clinical practice to establish the risk of developing metastasis, the presence of mutations in the succinate dehydrogenase type B (SDHB) gene is generally considered as the strongest single risk factor associated with a significant risk of metastatic disease, leading to metastases in 40% or more of patients [1,19,20].