The interval approach: an adaptation of the liver-first approach to treat synchronous liver metastases from rectal cancer

Background: The waiting interval after chemoradiotherapy (CRT) is an interesting therapeutic window to treat patients with synchronous liver metastases (SLM) from rectal cancer. Methods: A retrospective analysis was performed of 18 consecutive patients (M/F 10/8, age (range) 60 (51-75) years) from five institutions who underwent liver resection of SLM during the waiting interval after CRT for rectal adenocarcinoma. Results: All patients underwent interval liver surgery for a median (range) of 4 (2-14) liver metastases. Metastases involved a median (range) of 4 (1-7) liver segments. Median (range) time between end of CRT and liver surgery was 22 (6-45) days. Laparoscopic liver surgery was performed in 12 (67%) patients. No severe complications (Clavien-Dindo >= 3b) occurred after liver surgery. Median (range) length of hospital stay after liver surgery was 5 (1-10) days. All patients subsequently underwent rectal resection at a median (range) of 10 (8-13) weeks after end of CRT. Median (IQR) time-to-progression after liver surgery was 4.2 (2.8-9.2) months. Conclusions: The waiting interval after neoadjuvant CRT is a valuable option to treat SLM from rectal cancer. More data are necessary to confirm its oncological efficacy.