Table 3.

FDG-PET measurements and pathological classification

	Pathological responder TRG1–2 (N = 17)	Pathological nonresponder TRG3–5 (N = 23)	P-value
Pre-SUV	7.5 ± 5.2	8.8 ± 6.8	0.5103
Post-SUV	2.0 ± 1.7	5.1 ± 3.9	0.0038
∆SUV	5.4 ± 5.8	3.7 ± 3.8	0.2502
DR(%)	65.3 ± 32.3	35.4 ± 21.7	0.0012

Abbreviations: TRG the Mandard tumor regression grade, FDG-PET, ¹⁸F-fluorodeoxyglucose positron emission tomography, SUV, standardized uptake value, Pre-SUV, SUVmax values on the initial scan, Post-SUV, SUVmax values on the post-CRT scan, ∆SUV, ∆SUV = Pre-SUV– Post-SUV, DR, decreasing rate: DR = ∆SUV/ Pre SUV × 100(%), CRT, chemoradiation therapy