Table 4. .

Comparison of response categories between conventional and immune-related criteria

	WHO	IrRC	RECIST 1.0	RECIST 1.1	irRECIST	iRECIST
CR	Complete resolution of lesions (confirmed at 4 weeks)	Complete resolution of lesions (confirmed at 4 weeks) from first irCR scan	Complete resolution of lesions	Complete resolution of non-nodal lesions and < 10 mm short-axis for lymph nodes	Complete resolution of non-nodal lesions and < 10 mm short-axis for lymph nodes. No confirmation necessary	Complete resolution of non-nodal lesions and < 10 mm short-axis for lymph nodes. No new lesions
PR	≥50% decrease in tumour burden (confirmed at 4 weeks)	≥50% decrease in tumour burden (confirmed at 4 weeks)	≥30% decrease in tumour burden	≥30% decrease in tumour burden	≥30% decrease in tumour burden	≥30% decrease in tumour burden
SD	Does not meet criteria for CR/PR/PD	Does not meet criteria for irCR/irPR/irPD	Does not meet criteria for CR/PR/PD	Does not meet criteria for CR/PR/PD	Does not meet criteria for irCR/irPR/irPD	Does not meet criteria for iCR/iPR/iUPD/iCPD
PD	≥25% increase in tumour burden relative to nadir; new lesions	≥25% increase in tumour burden relative to nadir; new lesions. Confirmation of PD via a subsequent scan ≥ 4 weeks later is required	≥20% increase in tumour burden relative to nadir; new lesions	≥20% increase in tumour burden relative to nadir and a minimum absolute increase of 5 mm; new lesions	≥20% increase in tumour burden relative to nadir and a minimum absolute increase of 5 mm; new lesions. Confirmation of PD via a subsequent scan ≥ 4 weeks later to detect delayed responses is required	iUPD—presence of new measurable/non- measurable lesions, or ≥ 20% increase in tumour burden relative to nadir iCPD-confirmation of IUPD with >/= 5 mm increase in size of target or new target lesions, increase in non-target or new non-target or increase in number of new lesions.

CR, complete response; iCPD, immune-confirmed progressive disease; iCR, immune complete response; iPR, immune partial response; irCR, immune-related complete response; irPR, immune-related partial response; irPD, immune-related progressive disease; irRC, immune-related response criteria; irRECIST, immune-related Response Evaluation Criteria in Solid Tumours; iUPD, immune–unconfirmed progressive disease; PD, progressive disease; PR, partial response; RECIST, Response Evaluation Criteria in Solid Tumours; SD, stable disease; WHO, World Health Organization.