Table 2.

Sensitivity and specificity of different possible thresholds for dichotomizing tumors into EGFR mutant and EGFR WT groups

ThresholdSensSpec
Unidimensional
    Optimal*7.0% Decrease71%78%
    Alternate9.0% Decrease52%85%
    RECIST30% Decrease14%100%
Volumetric
    Optimal*24.9% Decrease90%89%
    RECIST65% Decrease14%96%

Abbreviations: Sens, sensitivity = percentage of EGFR mutant tumors classified as responders; Spec, specificity = percentage of EGFR WT tumors classified as nonresponders.

  • *Threshold calculated to have highest summed sensitivity and specificity.

  • Threshold outside of the 95% limits of agreement with the highest summed sensitivity and specificity.