Contribution of surgical specialization to improved colorectal cancer survival. BJS 2013; 100: 1388-1395.

Results

The 1823 patients who had surgery in 2001–2004 were more likely to have had stage I or III tumours, and to have undergone surgery with curative intent than the 1715 patients operated on in 1991–1994. The proportion of patients presenting electively who received surgery by a specialist surgeon increased over time (from 14·9 to 72·8 per cent; P < 0·001). Postoperative mortality increased among patients treated by non‐specialists over time (from 7·4 to 10·3 per cent; P = 0·026). Non‐specialist surgery was associated with an increased risk of postoperative death (adjusted odds ratio 1·72, 95 per cent confidence interval (c.i.) 1·17 to 2·55; P = 0·006) compared with specialist surgery. The 5‐year relative survival rate increased over time and was higher among those treated by specialist compared with non‐specialist surgeons (62·1 versus 53·0 per cent; P < 0·001). Compared with the earlier period, the adjusted relative excess risk ratio for the later period was 0·69 (95 per cent c.i. 0·61 to 0·79; P < 0·001). Increased surgical specialization accounted for 18·9 per cent of the observed survival improvement.