Influence of Individual Surgeon Volume on Oncological Outcome of Colorectal Cancer Surgery

Table 5

Univariate and multivariate analysis of overall survival.

Characteristics		Univariate			Multivariate
		HR	95% CI	value	HR	95% CI	value
Low-volume surgeon	451	1.000			1.000
High-volume surgeon	321	0.495	0.35–0.69	<0.001	0.731	0.51–1.04	0.09
Age in years				<0.001			<0.001
<50	41	1.000			1.000
50–75	494	1.068	0.58–1.98		1.110	0.82–1.77
>75	237	2.426	1.30–4.52		1.578	1.45–1.76
ASA-classification [16]				<0.001			0.01
1	158	1.000			1.000
2	410	1.384	0.92–2.08		1.340	0.83–2.16
3	181	2.726	1.78–4.17		1.973	1.16–3.36
4	25	5.398	3.07–9.49		3.136	1.54–6.41
Comorbidity	523	1.509	1.13–2.01	<0.001	1.089	0.71–1.68	0.70
Cardiac	155	1.569	1.17–2.11	<0.001	1.190	0.79–1.79	0.40
Vascular	244	1.427	1.10–1.86	<0.001	1.084	0.78–1.52	0.64
Neurologic	56	1.663	1.09–2.54	0.02	1.190	0.92–2.41	0.10
Urogenital	66	1.749	1.20–2.54	<0.001	1.215	0.78–1.89	0.39
Open surgical technique	258	1.000			1.000
Laparoscopic	514	0.522	0.41–0.67	<0.001	0.595	0.43–0.83	<0.001
No conversion	400	1.000			1.000
Conversion (laparoscopy only)	114	1.510	1.10–2.08	0.01	1.418	0.93–2.16	0.10
Blood loss intraoperatively	772	1.001	1.00–1.01	<0.001	1.000	1.00–1.00	0.63
Tumor stage				<0.001			0.67
1	50	1.000			1.000
2	156	1.235	0.57–2.66		1.507	0.64–3.58
3	495	1.999	0.98–2.66		1.435	0.64–3.23
4	60	4.956	2.30–10.7		1.952	0.78–4.88
Nodal stage				<0.001			<0.001
0	445	1.000			1.000
1	218	2.262	1.68–3.04		1.959	1.34–2.87
2	108	4.997	3.61–6.92		3.091	1.77–5.40
3	1	14.03	1.94–101		5.660	0.65–49.6
Metastatic stage				<0.001			<0.001
0	695	1.000			1.000
1	77	5.020	3.73–6.76		3.883	1.34–2.87
Number of positive lymph nodes	772	1.134	1.11–1.16	<0.001	1.042	0.99–1.10	0.13
Resection margins				<0.001			0.08
Complete resection (R0)	742	1.000			1.000
Microscopically irradical (R1)	19	3.520	2.05–6.05		2.294	1.08–4.89
Macroscopically irradical (R2)	11	4.153	2.12–8.12		1.798	0.71–4.53
No adverse event	665	1.000			1.000
Adverse event	107	1.938	1.42–2.65	<0.001	1.129	0.70–1.82	0.62
No adjuvant chemotherapy	554	1.000			1.000
Adjuvant chemotherapy	218	1.517	1.17–2.98	<0.001	1.174	0.79–1.74	0.43

Only significant factors listed; 3 low-volume patients lost to follow-up; according to the AJCC TNM-staging system [17].