The role of surgery for locally recurrent and second recurrent rectal cancer with metastatic disease.

Background: The role of surgery for locally recurrent rectal cancer (LRRC) with resectable distant metastases or second LRRC remains unclear. This study aimed to clarify the influence of synchronous distant metastases (SDMs), a history of distant metastasis resection (HDMR), and a second LRRC on the outcome.

Methods: The long-term outcomes of 70 surgically treated patients with LRRC between 2006 and 2018 were compared by SDM (n = 10), HDMR (n = 17), and second LRRC (n = 7).

Results: Among the 10 patients with SDM, 4 patients underwent simultaneous resection, whereas the other 6 underwent staged resection with distant first approach. Recurrence developed in 9 patients, of which 2 patients with liver re-resection achieved long-term survival without cancer. The patients with and without SDM had equivalent 5-year overall survival rate (40.5% vs. 53.3%, p = 0.519); however, patients with SDM had a worse 3-year recurrence-free survival rate than those without SDM (10.0% vs. 37.5%, p = 0.031). Multivariate analysis showed that primary non-sphincter-preserving surgery, second LRRC, and R1 resection were independent risk factors for overall survival. Similarly, primary non-sphincter-preserving surgery, second LRRC, SDM, and R1 resection were risk factors for recurrence-free survival.

Conclusions: Patients with SDM might still be suitable to undergo salvage surgery and achieve favourable overall survival. Distant metastasectomy should be performed first, followed by a sufficient interval to avoid unnecessary LRRC resection in uncurable patients. An HDMR should not be taken into consideration when making surgical plans. Surgical indication of second LRRC should be strict, especially in referred patients.