Wachtel H, Hutchens T, Baraban E, Schwartz LE, Montone K, Baloch Z, LiVolsi V, Krumeich L, Fraker DL, Nathanson KL, Cohen DL, Fishbein L. Predicting Metastatic Potential in Pheochromocytoma and Paraganglioma: A Comparison of PASS and GAPP Scoring Systems. J Clin Endocrinol Metab. 2020 12 01; 105(12).