Characteristics and Prognostic Significance of Preoperative Magnetic Resonance Imaging-Assessed Circumferential Margin in Rectal Cancer

Table 2

The association between radiological and clinicopathological characteristics and patients’ outcomes.

Characteristics	Number (%)	LR			DFS			OS
		HR	95% CI	value	HR	95% CI	value	HR	95% CI	value
Age, years
65	113 (55.7)	1			1			1
65	90 (44.3)	1.40	0.65–3.05	0.393	1.60	0.91–2.83	0.105	3.16	1.38–7.24	0.007
Sex
Male	104 (51.2)	1			1			1
Female	99 (48.8)	0.77	0.36–1.69	0.518	0.72	0.41–1.29	0.271	1.06	0.46–2.44	0.899
Preoperative CEA
5 ng/L	147 (72.4)	1			1			1
5 ng/L	56 (27.6)	2.75	1.27–5.96	0.011	1.11	0.59–2.10	0.749	2.36	1.05–5.34	0.038
mrT classification
mrT1-2	30 (14.8)	1			1			1
mrT3	173 (85.2)	30.9	0.59–1606	0.089	4.36	1.35–14.1	0.014	9.01	1.21–67.1	0.032
mrN classification
mrN (−)	114 (56.2)	1			1			1
mrN (+)	89 (43.8)	2.12	0.96–4.70	0.063	1.12	0.64–1.98	0.69	1.54	0.69–3.45	0.296
mrCRM
Clear	171 (84.2)	1			1			1
Involved	32 (15.8)	4.41	2.05–9.51	0.0001	2.22	1.22–4.05	0.009	3.02	1.30–7.00	0.01
Location of closest mrCRM in bowel wall
Anterior	107 (52.7)	1			1			1
Lateral/posterior	96 (47.3)	0.57	0.25–1.28	0.173	0.78	0.44–1.38	0.390	0.75	0.33–1.69	0.483
Peritoneal reflex relationship
Above	39 (19.2)	1			1			1
Below	164 (80.8)	2.67	0.80–8.92	0.111	3.07	1.21–7.78	0.018	2.99	0.89–10.0	0.077
Tumor distance from anal verge
5 cm	85 (41.9)	1			1			1
5 cm	118 (58.1)	1.56	0.69–3.50	0.284	0.94	0.53–1.65	0.822	1.61	0.69–3.77	0.269
pT classification
pT1-2	60 (29.6)	1			1			1
pT3-4	143 (70.4)	12.2	1.65–89.9	0.014	5.43	1.95–15.1	0.001	12.2	1.65–90.7	0.014
pN classification
pN (−)	113 (55.7)	1			1			1
pN (+)	90 (44.3)	5.31	2.00–14.1	0.001	2.36	1.31–4.28	0.004	2.67	1.13–6.30	0.025
pCRM
pCRM (−)	189 (93.1)	1			1			1
pCRM (+)	14 (6.9)	4.66	1.75–12.4	0.002	2.60	1.10–6.14	0.029	0.92	0.12–6.83	0.933
Tumor grade
Low-medium	170 (83.7)	1			1			1
High	33 (16.3)	1.28	0.48–3.42	0.612	1.94	1.01–3.73	0.048	1.41	0.48–4.23	0.536
Adjuvant treatment
No treatment	67 (33.0)	1			1			1
Chemotherapy	69 (34.0)	3.65	1.19–11.2	0.024	3.43	1.45–8.12	0.005	5.06	1.43–17.8	0.012
Chemoradiotherapy	67 (33.0)	2.40	0.74–7.85	0.145	3.53	1.49–8.36	0.004	3.34	0.89–12.7	0.076

LR, local recurrence; DFS, disease-free survival; OS, overall survival; mrCRM: MRI-assessed circumferential margin; pCRM: pathological circumferential margin.