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.