Published online Jun 10, 2017. doi: 10.5306/wjco.v8.i3.266
Peer-review started: December 5, 2016
First decision: March 28, 2017
Revised: April 12, 2017
Accepted: May 3, 2017
Article in press: May 5, 2017
Published online: June 10, 2017
Processing time: 182 Days and 20.9 Hours
To verify whether recurrence-free survival (RFS) surrogates overall survival (OS) in phase III trials for resectable colorectal liver metastases (CRLM).
MEDLINE, EMBASE, and Scopus databases were consulted. Eligible studies were phase III trials testing any type of systemic therapy (neoadjuvant, adjuvant or perioperative) added to surgery in patients with resectable CRLM. A linear regression model based on hazard ratios (HR) of OS and RFS was performed.
Of 3059 studies, 5 phase III trials (1162 patients) were included for analyses. A linear regression weighted by each trial was used to estimate the association between each HR and RFS. The originated formula was: OS HR = (0.93 × RFS HR) + 0.14; with RFS 95%CI (0.48-1.38), with P = 0.007.
This association suggests that RFS could work as a putative surrogate endpoint of OS in this population, avoiding bigger, longer and more resource-consuming trials. The OS could be assumed based on RFS and our model could be useful to better estimate sample size calculations of phase III trials of CRLM aiming for OS.
Core tip: This study addresses a systematic review of curative-intent treatment of colorectal liver metastasis looking for oncologic outcomes. We describe the association between overall survival (OS) and recurrence free survival in the setting of resectable colorectal liver metastases (CRLM). It suggests that recurrence free survival could work as a putative surrogate of OS in this population, avoiding bigger, longer and more resource-consuming trials. We do believe that our model can be useful to better estimate sample size calculations of superiority phase III trials of CRLM aiming for OS.