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

Table 4

Univariate and multivariate analysis of disease-free survival.

Characteristics		Univariate			Multivariate
		HR	95% CI	value	HR	95% CI	value
Low-volume surgeon	445	1.000			1.000
High-volume surgeon	316	0.566	0.44–0.74	<0.001	0.736	0.55–0.98	0.04
Age in years				0.01			<0.001
<50	41	1.000			1.000
50–75	486	1.052	0.61–1.80		1.261	0.67–2.37
>75	234	1.304	1.16–1.49		2.034	1.01–4.08
ASA-classification [16]				<0.001			0.05
1	158	1.000			1.000
2	410	0.938	0.68–1.29		0.914	0.63–1.33
3	181	1.547	1.09–2.19		1.301	0.86–1.97
4	25	2.567	1.65–4.62		1.507	1.05–2.86
Urogenital comorbidity	66	1.521	1.07–2.17	0.02	1.174	0.69–1.47	0.43
Open surgical technique	253	1.000			1.000
Laparoscopic	508	0.518	0.41–0.65	<0.001	0.752	0.55–1.03	0.08
No conversion	396	1.000			1.000
Conversion (laparoscopy only)	112	1.380	1.03–1.86	0.03	1.337	0.92–1.95	0.13
Elapsed time of the surgery	761	1.003	1.00–1.01	0.02	1.001	0.99–1.01	0.43
Blood loss intraoperatively	761	1.001	1.00–1.01	<0.001	1.000	0.99–1.00	0.20
Tumor stage				<0.001			0.04
1	50	1.000			1.000
2	153	1.293	0.63–2.67		1.307	0.59–2.91
3	489	2.549	1.31–4.97		1.666	0.79–3.52
4	58	6.609	3.21–13.6		2.814	1.21–6.54
Nodal stage				<0.001			<0.001
0	439	1.000			1.000
1	216	2.484	1.91–3.23		1.769	1.28–2.46
2	106	4.791	3.57–6.43		2.484	1.51–4.10
Metastatic stage				<0.001			<0.001
0	684	1.000			1.000
1	77	9.697	7.29–12.9		7.093	4.99–10.1
Positive lymph nodes	761	1.117	1.09–1.14	<0.001	1.031	0.98–1.08	0.21
Resection margins				<0.001			0.29
Complete resection (R0)	731	1.000			1.000
Microscopically irradical (R1)	19	2.955	1.76–4.97		1.200	0.60–2.38
Macroscopically irradical (R2)	11	3.080	1.58–6.00		0.551	0.23–1.32
Length of hospital-stay	761	1.012	1.01–1.02	<0.001	1.004	0.99–1.01	0.39
No adverse event	656	1.000			1.000
Adverse event	105	1.664	1.24–2.23	0.01	1.069	0.69–1.65	0.76
No adjuvant chemotherapy	546	1.000			1.000
Adjuvant chemotherapy	215	2.104	1.67–2.65	<0.001	1.376	0.98–1.93	0.06

Only significant factors listed; 13 patients lost to follow-up, 8 low-volume patients, and 5 high-volume patients; according to the AJCC TNM-staging system [17].