Table 1.

Characteristic of available meta-analysis on prognostic and predictive value of microsatellite instability (MSI).

Study, Year	Number of Included Trials	Number of Patients	CRC Stage	Received Treatment	MSI Status	Main Findings	Predictive Value of MSI Status
Popat et al., 2005 [53]	32	7642	I–IV	5-FU-based adjuvant chemotherapy vs. control group	1277 MSI	MSI-H status established as a prognostic factor; no benefit from adjuvant FU for MSI patients	Not assessed
Guastadisegni et al., 2010 [64]	31	12,782	I–IV	5-FU-based adjuvant chemotherapy in combination with levamisole or leucovorin (in 6 studies) or mitomycin (in 1 study)	14% MSI (396 MSI, 2467 MSS)	MSI-H status established as a prognostic factor (association between MSI and favourable prognosis in term of OS and DFS; inconclusive results about predictive value of MSI status due to the high inter-study heterogeneity	Inconclusive results
Webber et al., 2015 [80]	16	9312	I–IV	5-FU-based chemotherapy vs. control group	15% MSI	No difference in the effect of treatment based on MSI status	Not proven
Des Guetz et al., 2009 [81]	7	3690	II–III	5-FU-based adjuvant chemotherapy vs. control group	14% MSI (454 MSI-H; 3690 MSS)	MSI-H status established as a predictive factor of non response to 5-FU-based chemotherapy in CRC patients stage II or III	Proven for patients stage II/III
Des Guetz et al., 2009 [82]	6	964	IV	5-FU-based chemotherapy or combinations of 5-FU or capecitabine with oxaliplatin and/or irinotecan	9% MSI (91 MSI-H, 873 MSS)	No difference in the effect of treatment of patients with metastatic CRC in terms of RR based on MSI status	Not proven for mCRC patients

CRC, colorectal cancer; FU, fluorouracil; MSS, microsatellite stable; MSI-H, high-frequency MSI; OS, overall survival; DFS, disease free survival; RR, response rate; mCRC, metastatic colorectal cancer.