Table 1.

Studies evaluating the impact of MMR status on the efficacy of 5-FU-based treatment in CRC.

References	Analyzed/Total	MSI Frequency	Disease Stage	Treatment	Result
Sargent et al. (2010) [53]	457	15%	Stage II & III	FU/LEV or FU/LV vs. No Treatment	Reduced OS in dMMR Tumors Receiving FU-based Adjuvant Therapy (HR, 2.95; 95% CI, 1.02–8.54; p = 0.04)
Jover et al. (2009) [60]	505/754	10.1%	Stage II & III	5-FU-based vs. No Treatment	Reduced Survival in dMMR Tumors Receiving FU-based Adjuvant Therapy (pMMR Log Rank p = 0.00001; dMMR Log Rank p = 0.7)
Tejpar et al. (2009) [61]	1254/3278	22% stage II 12% stage III	Stage II & III	5-FU/FO vs. 5-FU/FO/CPT-11	Prognostic Effect of dMMR in Patients Treated with 5-FU
Sargent et al. (2008) [62]	341	13.8%	Stage II & III	5-FU/LEV, 5-FU/FO vs. No Treatment	Reduced OS (pMMR HR, 0.69; p = 0.047; dMMR HR, 1.26; p = 0.68) and DFS (pMMR HR, 0.59; p = 0.004; dMMR HR, 1.41; p = 0.53) in dMMR Tumors Receiving 5-FU-based Adjuvant Therapy
Kim et al. (2007) [56]	542	18.1%	Stage II & III	FU/LV vs. No Treatment	No Difference was Found by dMMR Status.
Westra et al. (2005) [54]	273/391	16%	Stage III	FU-based Chemotherapy	In a Multivariate Model, dMMR Status was not Associated with DFS.
Ribic et al. (2003) [52]	570	16.7%	Stage II & III	5-FU-based Chemotherapy vs. No Treatment	Reduced OS (pMMR HR, 0.72; p = 0.04; dMMR HR, 1.07; p = 0.80) in dMMR Tumors Receiving 5-FU-based Adjuvant Therapy
Hemminki et al. (2000) [55]	1044	12%	Stage III	5-FU-based Chemotherapy	Improved RFS in dMMR Tumors (p = 0.020)
Elsaleh et al. (2000) [57]	656	8.5%	Stage III	5-FU-based Chemotherapy	Better Survival in dMMR Tumors (p = 0.0007)

Abbreviations: dMMR, deficient mismatch repair; CRC, colorectal cancer; 5-FU, 5-fluorouracil; FO, folinic acid; CPT-11, irinotecan; LV, leucovorin; LEV, levamisole; PFS, progression-free survival; HR, hazard ratio; MSI, microsatellite instability; OS, overall survival; DFS, disease-free survival; RFS, recurrence-free survival; pMMR, proficient mismatch repair.