Background: The treatment options for patients with therapy refractory 
metastatic colorectal cancer (mCRC) are sparse. TAS-102 (FTD/TPI) is a new oral 
anti-tumour agent composed of a nucleoside analogue, trifluridine, and a 
thymidine phosphorylase inhibitor, tipiracil, indicated for patients with mCRC 
who are refractory to standard therapies. This study summarizes published and 
unpublished experience with FTD/TPI in clinical practice settings. Patients and 
methods: The Medline/PubMed, Embase and Cochrane Library databases were searched 
to identify observational studies on FTD/TPI monotherapy for mCRC. Papers 
describing use of FTD/TPI monotherapy outside clinical trials in series of 
patients evaluable for effectiveness were eligible. The outcomes of interest 
were median progression free survival (mPFS), median overall survival (mOS) as 
well as mean PFS time restricted to six months (PFS6m) and mean OS time 
restricted to one year (OS1y). Results of the pooled analyses of observational 
studies were compared to the results of the Japanese phase II trial and the two 
phase III trials, RECOURSE and TERRA. Results: Seven published and two 
unpublished studies with 1008 patients from 64 centres were included for 
analysis. The pooled mPFS was 2.2 months (95% CI 2.1 to 2.3 months), and the 
pooled mOS was 6.6 months (95% CI 6.1 to 7.1 months). PFS6m was 2.9 months (95% 
CI 2.6 to 3.1 months) and OS1y was 6.8 (95% CI 6.0 to 7.5) months. While these 
results all reflect RECOURSE, the pooled mOS is lower than in the phase II trial 
and the OS1y is inferior to both the phase II trial and TERRA. Conclusion: This 
systematic review and a meta-analysis indicates that in real life settings, the 
survival benefit of FTD/TPI monotherapy in patients with therapy refractory mCRC 
reflects the outcomes in RECOURSE but is inferior to outcomes in the two Asian 
efficacy trials. What is already known TAS 102 (Lonsurf) is an oral fixed dose 
combination of trifluridine (FTD) and tipiracil (TPI) indicated as salvage-line 
treatment in patients with therapy refractory metastatic colorectal cancer 
(mCRC). A Japanese phase II trial and two phase III trials, RECOURSE and TERRA, 
demonstrated that FTD/TPI prolonged overall survival. What this study adds This 
systematic review and meta-analysis of real life data from 64 sites indicates 
that the effectiveness in daily clinical practice settings of FTD/TPI 
monotherapy in late stage mCRC reflects the outcomes in RECOURCE but is inferior 
to the outcomes in the Japanese phase II trial and TERRA.