MKI67 and paraganglioma: The PASS score (pheochromocytoma of the Adrenal gland Scaled Score) was the first [129], and it was based on morphological criteria not including Ki67, which was successively integrated with growth pattern, cellularity, comedo-type necrosis, angioinvasion, and capsular invasion in the GAPP (Grading system for Adrenal Pheochromocytoma and Paraganglioma) system [130].