Meta-analysis of survival based on resection margin status following surgery for recurrent rectal cancer

Aim To determine the presence and duration of survival advantages was investigated for resection margin status (R0, R1 or R2) following surgery for locally recurrent rectal cancer (LRRC). Method A systematic review of the literature was performed for studies comparing resection margin status for LRRC. Weighted mean differences and meta-analysis of hazard ratios were used as a measure of median and overall cumulative survival. Results Twenty-two studies were included, providing outcome for 1460 patients undergoing surgery for LRRC. 57% underwent an R0 resection, 25% an R1 resection and 11% an R2 resection. The most commonly performed operations were abdominoperineal excision (35%), exenteration (23%) and anterior resection (21%). The range of median survival per resection margin was R0 28-92 months, R1 12-50 months, R2 6-17 months. Patients undergoing an R0 resection survived on average for 37.6 (95% confidence interval: 23.5-51.7) months longer than those undergoing R1 resection and 53.0 (31.2-74.8) months longer than those undergoing R2 resection. This correlated to a hazard ratio of 2.03 (1.73-2.38) for R0 vs R1 and 3.41 (2.21-5.25) for R0 vs R2. Patients undergoing R1 resection survived on average 13.3 (7.23-19.4) months longer than those undergoing R2 resection [hazard ratio of 1.68 (1.33-2.12)]. Conclusion Patients undergoing R0 resection have the greatest survival advantage following surgery for recurrent rectal cancer. There is a survival advantage for R1 over R2 resection, but there may be no benefit of R2 resection over palliative treatment.