Table 2.

Overview PET(/CT)-based criteria for response assessment

	EORTC (1999)	PERCIST (2009)	PECRIT (2017)	PERCIMT (2018)	iPERCIST (2019)
Modality	PET	PET	PET/CT	PET/CT	PET/CT
Complete response	• Reduction of FDG uptake to background levels	• Reduction of FDG uptake to the level of background blood pool	• Disappearance of all metabolically active tumors and TL • SAD reduction target lymph nodes < 10 mm • No new lesions	• Complete resolution of all FDG-avid lesions • No new FDG-positive lesion	• Reduction of FDG uptake to the level of background blood pool
Partial response	• ≥ 15% reduction of FDG uptake	• ≥ 30% reduction in SULpeak • Min. 0.8 units of measurable lesions	• ≥ 30% reduction in SULpeak • ≥ 30% decrease in TL diameter sum	• Complete resolution of some FDG-avid lesions • No new FDG-positive lesion	• ≥30% reduction in SULpeak
Stable disease	• Neither CR, PR nor PD	• Neither CR, PR nor PD	• Neither CR, PR nor PD	• Neither CR, PR nor PD	• Neither CR, PR nor PD
Progressive disease	• ≥ 25% increase of FDG uptake	• > 30% increase in SULpeak • Min. 0.8 units of measurable lesions	• > 30% increase in SULpeak • Or new metabolically active lesion • ≥ 20% increase in target lesion diameter (Min. 5 mm) • Or new lesions	• Four or more new lesions of < 10 mm functional diameter • Or three or more new lesions >10 mm functional diameter • Or two or more new lesions > 15 mm functional diameter	UMPD: • ≥ 30% increase in SULpeak • or new FDG-positive lesion CPMD: • Confirmation of progression by second PET after 4–8 weeks later • Otherwise reset in case of PMR or SMD
Reference	[56]	[58]	[59]	[60, 61]	[30]

Abbreviations: TL target lesion; SUL SUV corrected for lean body mass; SAD short-axis-diameter, UPMD unconfirmed progressive metabolic disease; CPMD confirmed progressive metabolic disease; PMR partial metabolic response; SMD stable metabolic disease