Table 3.

Strengths, weaknesses and recommendations for three predictive MSI-H/dMMR biomarkers for ICI response.

Assays	Strengths	Weaknesses	Recommendations
IHC for dMMR	Simple Fast Cost-effective Widely available	Too many variables Hard to determine cut-off Relatively low analytic sensitivity and accuracy	First choice in general Use of all four antibodies Use for colorectal cancer and other spectrum of Lynch syndrome when suitable
PCR for MSI-H	Widely available Ease of use Accurate for colorectal cancer and other spectrum of Lynch syndrome	Capture partial MSI profiles Low prevalence in some tumor types	Use of five poly-A panel Use after neoadjuvant therapy or in advanced tumors
NGS for MSI-H	Capture full MSI profile Suitable for all tumor type More accurate and sensitive Simultaneous detection of other potential predictors	High cost Technical demands Lack of wide availability Need tumor-type specific cut-off	The last choice >300 genes in the panel Standardize technical parameters wherever possible