Evaluation of cancer treatment in the abdomen: Trends and advances

Table 1 Changes in lymphoma response definitions for clinical trials

	1999 response criteria	2007 response criteria
CR	Resolution of clinical and radiographic evidence of disease	Disappearance of disease; residual masses are allowed if previously PET positive and now PET negative
CR unconfirmed	May have a residual node greater than 1.5 cm in longest dimension, but SPD must be decreased by > 75%; or has indeterminate bone marrow	Category no longer used
PR	≥ 50% decrease in SPD, and no new or progressive sites of disease	≥ 50% decrease in SPD; may still be positive on PET, but no new lesions
Stable disease	Less than PR but more than PD	Not CR, PR, or PD
Relapsed or PD	Any new lesion or ≥ 50% increase in SPD from nadir	New lesion, PET positive or > 1.5 cm, or ≥ 50% increase in SPD or longest diameter of a previously involved node

PD: Progressive disease; PR: Partial response; CR: Complete response; PET: Positron emission tomography; SPD: Sum of the products of the greatest diameters.

Table 2 Traditional response evaluation criteria of solid tumors

Criteria	WHO[7]	RECIST[9]	RECIST 1.2[12]
CR	Disappearance of all known lesions	Disappearance of all target and non-target lesions - confirm at 4 wk	Disappearance of all target and non- target legions1
PR	≥ 50% decrease in sum of products of all lesions - confirm at 4 wk; no new lesions; no progression of any lesions	≥ 30% decrease from the baseline of the sum of max diameter of all lesions - confirm at 4 wk; no new lesions; no progression	≥ 30% decrease from the baseline of the sum of max diameter of all lesions; no new lesions; no progression1
SD	Neither PR nor PD	Neither PR nor PD	Neither PR nor PD
PD	≥ 25% increase of a single lesion over the smallest measurement or any new lesions	≥ 20% increase over the smallest sum of maximum diameter observed or any new lesions	≥ 20% increase over the smallest sum of maximum diameter and at least 5 mm increase or any new lesions

¹Confirmation at 4 wk required only for non-randomized trials with the primary end-point of response. CR: Complete response; PR: Partial response; PD: Progressive disease; SD: Stable disease; WHO: World Health Organization; RECIST: Response Evaluation of Criteria in Solid Tumors.