Table 5.

Mutation status of the four lung cancer whose tissue biopsies were positive for T790M or L878R.

Patient	Mutations Detected in Tissues	Mutations Detected in Plasma by the CRISPR	Mutations Detected in Plasma by ddPCR
1	T790M	T790M (Mean fluorescence intensity: 100000)
2	T790M
3	L858R	L858R (Mean fluorescence intensity: 99493)	L858R (10.13/µL)
4	T790M, L858R	L858R (Mean fluorescence intensity: 31419)	L858R (2 copes/µL)

The cut-off of mean fluorescence intensity >25,775 and 31,702 was set up in 20 age and gender-matched cancer-free smokers for the CRISPR-Cas12a system to determine positive L858R and T790M in plasma, respectively. The cutoff value for ddPCR to determine positive L858R and T790M in plasma was defined as two copies/µL, respectively.