Table 1.

Comparison of response criteria for GISTs.

RECIST Criteria	Response	Choi Criteria
Disappearance of all lesions. No new lesions.	Complete (CR)	Disappearance of all lesions. No new lesions.
30% decrease. No further increase.	Partial (PR)	≥10% decrease in size OR ≥15% decrease in density (HU on CT). No new lesions. No obvious progression of non-measurable disease.
Does not meet criteria for PR or PD	Stable disease (SD)	Does not meet criteria for complete response, partial response of progression. No clinical deterioration attributed to tumor progression
20% increase in size AND criteria for CR, PR or SD not met before increased disease.	Progression (SD)	≥10% increase in tumor size AND does not meet criteria of PR by tumor density on CT. New lesions. New intratumoral nodules or increase in size of previous intratumoral nodules.