Table 1.

Summary of measurement and response assessment approaches for bidimensional and unidimensional assessment based on irRC

Bidimensional assessment (the original irRC (7))Unidimensional assessment
Measurable lesions≥5 × 5 mm2 by bidimensional measurements≥10 mm in the longest diameter
Measurement of each lesionThe longest diameter × the longest perpendicular diameter (cm2)The longest diameter (cm)
The sum of the measurementsThe sum of the bidimensional measurements of all target lesions and new lesions if anyThe sum of the longest diameters of all target lesions and new lesions if any
Response assessmentPD: ≥25% increase from the nadirPD: ≥20% increase from the nadir
PR: ≥50% decrease from baselinePR: ≥30% decrease from baseline
CR: Disappearance of all lesionsCR: Disappearance of all lesions
New lesionsThe presence of new lesion(s) does not define progression. The measurements of the new lesion(s) are included in the sum of the measurements.
ConfirmationConfirmation by 2 consecutive observations not less than 4 weeks apart was required for CR, PR, and PD