Tumor-related imaging parameters predict response and survival after neoadjuvant chemoradiotherapy in rectal cancer

Table 1 Clinical and magnetic resonance image characteristics of non-sarcopenic and sarcopenic patients evaluated before neoadjuvant chemoradiotherapy for rectal cancer, n (%)/median (interquartile range)

Characteristics	Total (n = 133)	Non-sarcopenia (n = 98)	Sarcopenia (n = 35)	P value
Age (years)	56 (50, 64)	57 (50, 64)	56 (49, 66)	0.829
Maximum diameter of the tumor (mm)	37 (33, 45)	36 (33, 44)	40 (33.5, 46.5)	0.357
Length (mm)	56 (44, 68)	56 (44, 67.8)	57 (45, 69)	0.424
Short diameter of the largest lymph node (mm)	7 (5, 10)	7 (5, 10)	8 (5, 13)	0.718
Maximum diameter perpendicular to the intestinal wall on T2WI (mm2)	20 (15, 24)	20 (15, 24)	21 (15.5, 24.5)	0.272
Maximum cross-sectional area of the tumor on T2WI (mm2)	1064 (756, 1462)	962 (759, 1379)	1258 (789, 1720)	0.118
Distance of the tumor from the anal verge (mm)	51 (37, 72)	51.5 (36.2, 70.8)	50 (38.5, 73.5)	0.675
Carcinoembryonic antigen	3.77 (1.91, 13.05)	3.39 (1.78, 10.3)	5.05 (2.68, 20.2)	0.094
Carbohydrate antigen 19-9	12.23 (5.98, 27.80)	12.6 (6.46, 25.8)	9.92 (3.56, 32.5)	0.565
Body mass index (kg/m2)	22.87 (21.22, 25.10)	22.9 (21.3, 25.3)	22.9 (21.1, 24.1)	0.823
Sex
Male	93 (69.92)	60 (61.22)	33 (94.29)	< 0.01
Female	40 (30.08)	38 (38.78)	2 (5.71)
Circle
2	10 (7.52)	10 (10.20)	0 (0.00)	0.019
3	37 (27.82)	31 (31.63)	6 (17.14)
4	86 (64.66)	57 (58.16)	29 (82.86)
Signal
1	55 (41.35)	37 (37.76)	18 (51.43)	0.226
2	78 (58.65)	61 (62.24)	17 (48.57)
Spiculation
0	61 (45.86)	43 (43.88)	18 (51.43)	0.567
1	72 (54.14)	55 (56.12)	17 (48.57)
Node
0	94 (70.68)	72 (73.47)	22 (62.86)	0.333
1	39 (29.32)	26 (26.53)	13 (37.14)
Stratification
0	50 (37.59)	35 (35.71)	15 (42.86)	0.585
1	83 (62.41)	63 (64.29)	20 (57.14)
MRF status
0	63 (47.37)	51 (52.04)	12 (34.29)	0.108
1	70 (52.63)	47 (47.96)	23 (65.71)
Extramural vascular invasion status
0	55 (41.35)	39 (39.80)	16 (45.71)	0.682
1	78 (58.65)	59 (60.20)	19 (54.29)
ExtraMRF
0	86 (64.66)	65 (66.33)	21 (60.00)	0.641
1	47 (35.34)	33 (33.67)	14 (40.00)
Clinical T stage
2	2 (1.50)	2 (2.04)	0 (0.00)	0.696
3	60 (45.11)	44 (44.90)	16 (45.71)
4	71 (53.38)	52 (53.06)	19 (54.29)
Clinical N stage
0	29 (21.80)	22 (22.45)	7 (20.00)	0.971
1	51 (38.35)	38 (38.78)	13 (37.14)
2	50 (37.59)	36 (36.73)	14 (40.00)
3	3 (2.26)	2 (2.04)	1 (2.86)

0: No, negative or absent; 1: Yes, positive or present (excluding clinical T and N stage). MRF: Mesorectal fascia; T2WI: T2-weighted imaging.

Table 2 Univariate analysis of sarcopenia for tumor regression grades, T downstaging, and overall survival

Prognostic indicators	Odds ratio	95%CI	P value
Tumor regression grade	2.328	0.9948-2.960	0.062
dT	1.035	0.425-2.716	0.941
Overall survival	1.269	0.577-2.790	0.554

Table 3 Univariate and multivariate analysis of prognostic variables for tumor regression grades

Variables	Univariate analysis			Multivariate analysis
	HR	95%CI	P value	HR	95%CI	P value
Age	0.987	0.955-1.018	0.402
Maximum diameter of the tumor	1.018	0.986-1.053	0.282
Length	1.033	1.011-1.056	0.004	1.029	0.075-0.900	0.012
Short diameter of the largest lymph node	1.069	0.990-1.166	0.108
Maximum diameter perpendicular to the intestinal wall on T2WI	0.995	0.951-1.042	0.824
Maximum cross-sectional area of the tumor on T2WI	1.000	0.999-1.001	0.224
Distance of the tumor from the anal verge	1.011	0.998-1.026	0.118
Carcinoembryonic antigen	1.000	1.000-1.003	0.862
Carbohydrate antigen 19-9	1.000	0.999-1.002	0.616
Body mass index	1.044	0.919-1.188	0.511
Sex	0.676	0.316-1.458	0.314
Circle	0.877	0.485-1.537	0.652
Signal	1.524	0.743-3.131	0.249
Spiculation	0.998	0.488-2.031	0.996
Node	1.968	0.880-4.679	0.109
Stratification	0.560	0.258-1.179	0.134
MRF status	2.289	1.119-4.777	0.025	1.853	0.873-3.970	0.109
Extramural vascular invasion status	1.333	0.650-2.734	0.431
ExtraMRF	1.328	0.632-2.864	0.459
Clinical T stage	1.400	0.718-2.748	0.323
Clinical N stage	1.209	0.777-1.893	0.400
Sarcopenia	2.328	0.994-2.960	0.062

HR: Hazard ratio; MRF: Mesorectal fascia; T2WI: T2-weighted imaging.

Table 4 Univariate and multivariate analysis of prognostic variables for T downstaging

Variables	Univariate analysis			Multivariate analysis
	HR	95%CI	P value	HR	95%CI	P value
Age	1.011	0.975-1.047	0.553
Maximum diameter of the tumor	0.986	0.953-1.021	0.417
Length	0.990	0.970-1.011	0.333
Short diameter of the largest lymph node	0.947	0.876-1.023	0.158
Maximum diameter perpendicular to the intestinal wall on T2WI	1.034	0.980-1.099	0.252
Maximum cross-sectional area of the tumor on T2WI	1.000	0.999-1.000	0.27
Distance of the tumor from the anal verge	0.994	0.982-1.006	0.289
Carcinoembryonic antigen	0.998	0.994-1.001	0.245
Carbohydrate antigen 19-9	1.000	1.000-1.001	0.828
Body mass index	1.077	0.931-1.249	0.32
Sex	2.083	0.822-6.036	0.143
Circle	1.451	0.778-2.653	0.229
Signal	0.603	0.250-1.382	0.243
Spiculation	1.141	0.507-2.562	0.748
Node	1.019	0.430-2.565	0.968
Stratification	1.269	0.551-2.870	0.569
MRF status	4.456	1.881-11.532	0.001	3.409	1.038-12.369	0.049
Extramural vascular invasion status	1.225	0.539-2.756	0.623
ExtraMRF	1.451	0.621-3.621	0.403
Clinical T stage	4.928	2.170-12.340	0.000	1.705	0.461-6.369	0.421
Clinical N stage	0.782	0.464-1.295	0.345
Sarcopenia	1.035	0.425-2.716	0.941

HR: Hazard ratio; MRF: Mesorectal fascia; T2WI: T2-weighted imaging.

Table 5 Univariate analysis of prognostic variables for overall survival

Variables	Univariate analysis			Multivariate analysis
	HR	95%CI	P value	HR	95%CI	P value
Age	1.019	0.983-1.056	0.312
Maximum diameter of the tumor	1.015	0.983-1.049	0.365
Length	1.009	0.991-1.028	0.317
Short diameter of the largest lymph node	1.013	0.950-1.081	0.696
Maximum diameter perpendicular to the intestinal wall on T2WI	0.997	0.952-1.044	0.89
Maximum cross-sectional area of the tumor on T2WI	1.000	0.999-1.000	0.952
Distance of the tumor from the anal verge	1.001	0.989-1.014	0.832
Carcinoembryonic antigen	0.999	0.993-1.004	0.566
Carbohydrate antigen 19-9	1.000	0.998-1.002	0.938
Body mass index	0.990	0.877-1.117	0.871
Sex	0.697	0.297-1.632	0.406
Circle	1.120	0.632-1.989	0.696
Signal	2.046	0.931-4.499	0.075
Spiculation	1.008	0.480-2.114	0.984
Node	2.655	1.281-5.503	0.009	2.199	0.965-5.014	0.061
Stratification	0.918	0.425-1.983	0.828
MRF status	2.149	1.005-4.596	0.049	1.5013	0.636-3.543	0.354
Extramural vascular invasion status	1.955	0.900-4.245	0.090
ExtraMRF	1.936	0.931-4.029	0.077
Clinical T stage	1.797	0.865-3.734	0.116
Clinical N stage	1.592	0.993-2.552	0.053
Sarcopenia	1.269	0.577-2.790	0.554

HR: Hazard ratio; MRF: Mesorectal fascia; T2WI: T2-weighted imaging.