Table 4.

Association between the mtDNA microsatellite instability and the risk and prognosis in CRC.

Sample type	Findings	Potential utility	Ref
CRC tissues (n = 100) and the corresponding noncancerous tissues.	The mtMSI was found in 30% of CRCs and it was associated with the poor prognosis.	Risk evaluation and prognosis evaluation	[65]
83 CRC tissues with a MSI tumor (including 39 patients with Lynch syndrome) and in 99mCRC patients with a microsatellite stable (MSS) tumor.	The mtMSI was high in mCRC patients with both MSI and MSS tumors, but no correlation with prognosis.	Risk evaluation and prognosis evaluation	[51]
The microdissected cancer epithelia and adjacent stromas of 48 sporadic CRCs.	The stromal mtMSI had no association with stromal nMSI or epithelial mtMSI.	Risk evaluation	[66]
CRC tissues (n = 35) and the corresponding noncancerous tissues.	mtMSI [310＇C＇ insertion (p = 0.00001) and T16189C (p = 0.0007)] was increased in the CRC tissues.	Risk evaluation	[67]

Recent studies showed that nuclear genome microsatellite instability was the significant predictor of prognosis CRCs. But the association between the mtDNA microsatellite instability and the risk and prognosis needs to be further confirmed.