Table 1. EORTC metabolic response group definitions.

EORCT Metabolic response
Progressive metabolic disease (PMD)	Increase of at least 25% in ΣSUVmax or a visible increase in extent of FDG uptake (>20% in longest dimension) or appearance of new metastatic lesion(s)
Stable metabolic disease (SMD)	Response between PMR and PMD
Partial metabolic response (PMR)	Reduction in ΣSUVmax of at least 25%
Complete metabolic response (CMR)	Complete resolution of FDG uptake within all lesions (making them indistinguishable from surrounding tissue)

ΣSUVmax: Sum of target lesions SUVmax

EORTC = European Organization for Research and Treatment of Cancer