Table 1.

Modified computed tomography response evaluation criteria for gastrointestinal stromal tumors

Response	Definition
Complete response	Disappearance of all lesions; No new lesions
Partial response	A decrease in size1 of ≥ 10% or decrease in tumor density (HU) ≥ 15% on CT; No new lesions; No obvious progression of nonmeasurable disease
Stable disease	Dose not meet criteria for complete response, partial response, or progressive disease; No symptomatic deterioration attributed to tumor progression
Progressive disease	An increase in tumor size of ≥ 10% and does not meet criteria of partial response by tumor density (HU) on CT; New lesions; New intratumoral nodules or increase in size of existing intratumoral nodules

¹The sum of longest diameters of target lesions as defined in RECIST. CT: Computed tomography.