A nomogram is a 2-dimensional calculating device or alignment chart designed to allow the approximate computation of a function. The use of such a mathematical model for treatment of aggressive and rare diseases is objective and individualized. Like a slide rule, its accuracy is limited to the precision with which “markings” can be drawn and aligned. Kim and colleagues1 have precisely described a coordinate system that can be easily reproduced to predict disease-free and overall survival after intended curative resection of adrenocortical carcinoma. The constants chosen were independent prognostic variables specific to the patient and the tumor.