Stage and size using magnetic resonance imaging and endosonography in neoadjuvantly-treated rectal cancer

Table 1 Demographic and histopathological data of 21 patients assessed for both stage and size before chemotherapy

Age, median (IQ range)	60 (60-66)
Gender (male/female)	17/4
Surgery (AR/APR/Hartman)	13/8/0
Laparoscopy (yes/no)	10/11
Differentiation grade (G1/2/3/4)	0/19/0/0 (2 not classified)
T-stage (T1/2/3/4)	2/8/9/2
N-stage (N0/1/2)	12/6/3
Assessed nodes, median (IQ range)	15 (14-18)

Table 2 Feasibility and accuracy of the tumour node metastasis staging, with stage II as the cut-off, using magnetic resonance imaging, endosonography and a combination (combo) of assessments of lymph nodes using magnetic resonance imaging and assessments of perirectal tissue penetration using endosonography compared with the histopathology of resected specimens in 23 patients before and after chemotherapy

	MRI-pre	ERUS-pre	Combo-pre	MRI-post	ERUS-post	Combo-post
Feasibility of stage	1.00	0.81
Feasibility of size	0.97	0.74
Accuracy of differentiating stages I/II	0.65	0.70	0.74	0.65	0.78	0.83
Sensitivity of differentiating stages I/II	0.73	0.87	0.87	0.73	0.80	0.93
Specificity of differentiating stages I/II	0.5	0.38	0.50	0.50	0.75	0.62
Kappa value of differentiating stages I/II	0.23	0.26	0.40	0.23	0.53	0.58
Overstaging of differentiating stages I/II	0.17	0.22	0.17	0.17	0.087	0.13
Understaging of differentiating stages I/II	0.17	0.087	0.087	0.17	0.13	0.048
Accuracy of perirectal penetration	0.48	0.70		0.52	0.78
Accuracy of lymph node detection	0.74	0.56		0.74	0.74

The last two columns present the accuracy of the prediction of perirectal tissue penetration and lymph nodes using magnetic resonance imaging (MRI) and endosonography (ERUS).

Table 3 Tumour length (median and range in mm) and the area (median and range in mm) using magnetic resonance imaging and endosonography before and after chemotherapy in 18 patients

Modality	Before chemotherapy		After chemotherapy		Specimen
	Length	Area	Length	Area	Length
MRI	47 (36-68)	641 (283-1345)	44 (19-68)	616 (156-1431)	Not applicable
ERUS	46 (29-59)	680 (290-2110)	41 (15-56)	595 (100-1380)	Not applicable
Histopathology	Not applicable	Not applicable	Not applicable	Not applicable	34 (12-70)

MRI: Magnetic resonance imaging; ERUS: Endosonography.