Anastomotic leakage after surgery for rectal cancer: a risk factor for local recurrence, distant metastasis and reduced cancer-specific survival?

Aim The impact of anastomic leakage (AL) on the oncological outcome after anterior resection (AR) for rectal cancer is still controversial. We explored the impact of AL regarding local recurrence (LR), distant metastasis and overall recurrence (OAR). Overall and cancer-specific survival was analysed. Method Patients undergoing AR for rectal cancer with a registered AL between 1995 and 1997 and a control group were identified in the Swedish Rectal Cancer Registry. The medical records were retrieved for additional data and validation. Differences in the oncological outcome at 5-year follow-up were analysed with multivariate methods. Results After validation, 114 patients with AL and 136 control patients with locally radical surgery for tumours in tumour-node-metastasis stages I-III were analysed. There was no difference detected between patients with AL and control patients regarding rates of LR [8% (9 of 114) vs 9% (12 of 136); P = 0.97], distant metastasis [18% (20 of 114) vs 23% (31 of 136); P = 0.37] and OAR [19% (22 of 114) vs 28% (38 of 136); P = 0.15]. The 5-year cancer-specific survival was almost 80% in both groups. In multivariate analysis, AL was not a risk factor of LR, distant metastasis or OAR and had no impact on 5-year overall or 5-year cancer-specific survival. Irrespective of the occurrence of AL, preoperative radiotherapy (P = 0.055) and rectal washout (P = 0.046) reduced the LR rate, but did not influence survival. Conclusion Anastomotic leakage was not proved to be a risk factor of worse oncological outcome. Hence, additional adjuvant treatment or extended follow-up on the basis of the occurrence of AL after AR might not be justified.