TABLE 3

(Preoperative) Multimodality and Radiotherapy Treatment Response Evaluation in Primary Rectal Cancer

Stage	Authors	Year	Reference	No. of patients	Therapy	Timing after therapy of PET evaluation	PET response criteria	Outcome measures	Results	P
Recurrent nonresectable tumor	Engenhart et al.	1992	40	21	Radiotherapy	8–9 wk	SUV normalization to background	Local control	PPV 20%; NPV 67%
cT3NXM0	Schiepers et al.	1999	41	9	Radiotherapy	2–3 wk	−ΔMR_glu	Histopathology, cell kinetics	Accuracy 80%
cT3 or N1	Guillem et al.	2000	49	15	Chemoradiation	4–5 wk	−ΔSUV, visual response score, −δTLG	Histopathology	PPV 100%
cT2, cT3, cT4, N1, N2, or N3	Oku et al.	2002	46	40	Radiotherapy	3–5 wk	SUV cutoff level after radiotherapy 3.2; SUV ratio	Recurrence, CT shrinkage rate	Responders <3.2; nonresponders >3.2 Correlation −0.383	0.046 0.014
cT3 or cT4	Amthauer et al.	2004	44	20	Chemoradiation + hyperthermia	2–4 wk	−ΔSUV_max,BSA > 36%	Histopathology	PPV 93%; NPV 100%	<0.001
cT2NXM0, cT3NXM0, or cT4NXM0	Calvo et al.	2004	50	25	Chemoradiation	4–5 wk	−ΔSUV_max	Histopathology (T downstaging)	Responders −3.3; nonresponders −1.9	0.03
cT3, cT4, or N1	Guillem et al.	2004	51	15	Chemoradiation	4–5 wk	−ΔSUV_max ≥ 62.5%, visual response score, −δTLG ≥ 69.5%	Recurrence, overall survival, recurrence-free survival	Responders −69%; nonresponders 37%	0.004
cT3 or cT4	Denecke et al.	2005	52	23	Chemoradiation + hyperthermia	2–4 wk	−ΔSUV_max > 36%	Histopathology (T downstaging)	Responders −60%; nonresponders −37%	0.03
									PPV 77%; NPV 100%	0.002
uT3, uT4, or N1	Konski et al.	2005	53	20	Chemoradiation	3–4 wk	−ΔSUV_max	Histopathology	Responders −75%; nonresponders −52%	0.24
cT3, cT4, or N1	Cascini et al.	2006	54	33	Chemoradiation	Day 12 during and after	−ΔSUV_mean > 52% (after 12 d)	Histopathology (tumor regression grade)	Responders −63%; nonresponders −22%; accuracy 100%	<0.0001
cT3, cT4, N1M0, N2M0, or N3M0	Capirci et al.	2006	55	88	Chemoradiation	5–6 wk	PET-positive	5-y overall survival	PET-negative: 5-y OS 91%; PET-positive: 5-y DFS 62%	0.024
							PET-negative (SUV_max < 0.9)	5-y disease-free survival	PET-negative: 5-y DFS 81%; PET- positive: 5-y OS 72%	0.003
cT3NXM0 or cT4NXM0	Kalff et al.	2006	56	34	Chemoradiation	7–43 d	Visual response score	Overall survival	CMR: 3-y PFS 100%; PMR: 3-y OS 79%	<0.0001
								Progression-free survival	CMR: 3-y OS 100%; PMR: 3-y PFS 47%	<0.0001
cT3 or cT4	Capirci et al.	2007	57	45	Chemoradiation	5–6 wk	−ΔSUV_max > 66.2%	Histopathology (tumor regression grade, T downstaging)	Responders −76%; nonresponders −47%; PPV 77%; NPV 89%; accuracy 80%	0.0015
cT3, cT4, or N1	Melton et al.	2007	58	21	Chemoradiation	4–5 wk	−ΔSUV_max > 70%, visual response score, −δTLG, −ΔCT/−ΔPET volume	Histopathology (T downstaging)	Responders −72%; nonresponders −44%; PPV 58%; NPV 100%	<0.001
cT3 or cT4	Kristiansen et al.	2008	59	30	Chemoradiation	7 wk	Visual response on PET/CT	Histopathology (tumor regression grade)	PPV 50%; NPV 58%
uT2N+ oruT3N0+	Siegel et al.	2008	47	32	Short course of radiotherapy	Days 7–8 after start	−ΔSUV_max > 40%	Histopathology (tumor regression grade)	No correlation between PET responses and outcome measures	NS
uT3, uT4, or N1	Nakagawa et al.	2008	48	59	Radiotherapy	2–3 wk	SUV cutoff level after radiotherapy 5	Median survival	Responders 95 mo; nonresponders 42 mo	0.042
								5-y overall survival	Responders 70%; nonresponders 44%
							SUV ratio < 100%		Relative risk 0.239	0.028
								Histopathology	Significant correlation	0.047
cT3 or cT4	Vliegen et al.	2008	60	20	Chemoradiation	4–6 wk	−ΔSUV_max	Histopathology (tumor regression grade)	Responders −83%; nonresponders −59%	0.025
cT3NX, cT4NX, or N1	Konski et al.	2008	61	53	Chemoradiation	3–4 wk	−ΔSUV_max	Histopathology, disease-free survival	Responders −67%; nonresponders −55%	0.08

PPV = positive predictive value; NPV = negative predictive value; ΔMR_glu = fractional change in MR_glu; ΔSUV = fractional change in SUV; SUV ratio = ratio of SUV between follow-up and baseline scans; ΔSUV_max,BSA = ΔSUV_max corrected for body surface area; ΔSUV_max = fractional change in SUV_max; ΔSUV_mean = fractional change in SUV_mean; OS = overall survival; DFS = disease-free survival; CMR = complete metabolic response; PFS = progression-free survival; PMR = partial metabolic response; ΔCT/ΔPET volume = change in lesion volume based on CT or PET measurements; NS = not significant.