Treatment of locally advanced rectal cancer and synchronous liver metastases: multicentre comparison of two treatment strategies.

Abstract

Management of locally advanced rectal cancer (LARC) has been optimized during recent times through (beyond) total mesorectal excision surgery and, more recently, the introduction of total neoadjuvant treatment (TNT)1–4. For patients with synchronous liver metastases, the optimal treatment strategy is less clear, with high variability among institutions worldwide5. In the Netherlands, two specific treatment sequences have mainly been used for treating LARC and synchronous liver metastases: the liver-first approach (LFA) and the M1 schedule6–8. The LFA consists of induction systemic chemotherapy, subsequent local treatment of the liver metastases, followed by long-course (chemo)radiotherapy and resection of the primary tumour. The rationale behind LFA is to treat the rectal tumour locally only when control of synchronous liver metastases has been established. Radiotherapy and primary tumour resection can be avoided in patients with disease progression during the first phase of the schedule9. The M1 schedule starts with preoperative short-course pelvic radiotherapy (5 × 5 Gy), followed by systemic therapy, and subsequent surgical treatment of both the liver and rectum (either simultaneously, liver first or primary tumour first). The advantage of starting with radiotherapy is the immediate downstaging effect on the primary tumour. This strategy has been proven safe and effective, and leads to excellent local control10.