Figure 5.

Analyses of tumor diameter (A,C,E) and plasma methoxytyramine (B,D,F) as predictors of metastatic disease. ROC curves relating changes in true-positive results (sensitivity) and false-positive results (1-specificity) for predicting the presence of malignancy as a function of changing cut-offs for mean tumor diameter are shown in panel A and for plasma methoxytyramine in panel B. Points of ROC curves closest to top left corners indicate values for true- and false-positive results used to estimate optimal cut-offs for tumor diameter in panel C and plasma methoxytyramine in panel D. Likelihoods of metastatic disease as a function of increasing tumor diameter in panel E and of increasing plasma methoxytyramine in panel F are shown separately for tumors with adrenal and extra-adrenal locations, assuming an overall frequency of malignancy of 10% for adrenal tumors and 36% for extra-adrenal tumors. Likelihoods of malignancy were then estimated based on differences in cumulative frequencies of tumors with and without metastases as a function of increasing mean diameter or plasma concentration of methoxytyramine.