Early prediction of histopathological response of rectal tumors after one week of preoperative radiochemotherapy using 18 F-FDG PET-CT imaging. A prospective clinical study

Table 4 Correlation between metabolic and histopathological responses

Author (country)	Year	N	2nd PET (weeks)	End-point	ΔSUV-MAX by response (%)	ΔSUV-MAX cut-off (%)	PPV (%)	NPV (%)	P value
Cascini¹³ (Italy)	2006	33¹	2	TRG	62 vs 28	52	100	87	<0.0001
Janssen¹⁴ (Netherlands)	2009	30	1	TRG²	29 vs 9	NA	NA	NA	0.013
Janssen¹⁴ (Netherlands)	2009	30	2	TRG	47 vs 18	43	91	82	0.001
Rosenberg¹⁵ (Germany)	2009	30	2	TRG	44 vs 30	35	82	58	0.085
Guerra¹⁶ (Italy)	2009	28	3	TRG	51 vs 43	49	75	42	NS
Lambrecht¹⁷ (Belgium)	2010	22³	2	pCR	59 vs 25	40	60	100	0.0036
Janssen¹⁹ (Netherlands)	2011	30	2	TRG	NR	48	100	79	<0.001
Janssen¹⁹ (Netherlands)	2011	21⁴	2	TRG	NR	48	83	93	0.001
Leibold¹ (USA)	2011	27⁵	1.5	pCR	27 vs 23	NR	NR	NR	0.68
Current (Israel)	2011	20⁶	1	pCR	35 vs	32	100	94	0.046
				TRG	1832 vs 17	NR	NR	NR	0.064

Abbreviations: NR – not relevant, NA – not available.
¹Patients received non-standard RCT, including also oxaliplatin and raltitrexed.
²A second end-point was prediction of ypT0-2 vs ypT3-4 by metabolic response.
³Two patients received non-standard RCT, including also oxaliplatin.
⁴The study included a validation cohort (n = 21); 5 patients were excluded from the analysis due to peritumoral inflammation.
⁵The study included 4 patients with metastatic disease; responders included complete and near complete pathological response (≥95% response).
⁶One patient was removed from per – protocol analysis because of delayed operation.

ISSN: 1748-717X