Mutant allele frequency predicts the efficacy of @entity470 -TKIs in @entity2220 harboring the XXXX mutation.

@entity1 @entity470 @entity2 @entity9512 @entity669 @entity2220
BACKGROUND: Whether the mutant allele frequency (MAF) may also have predictive implications for @entity669 kinase inhibitor (TKI) therapy in @entity1 with advanced @entity470 ( @entity470 )-mutated @entity2220 (AELAd) remains unknown. @entity1 AND METHODS: Based on a biobanking system in conjunction with our institution, we assessed @entity470 mutation status using pyrosequencing (Py) and by outsourcing laboratory tests, such as the Cycleave (Cy) and the Scorpion ARMS (A). RESULTS: Out of 705 @entity1 enrolled in the Shizuoka @entity2 Mutation Study between July 2011 and March 2013, 102 AELAd @entity1 were identified as carrying the @entity9512 mutation (L858Rm) using Py to analyze histological specimens. Of these 102 @entity1 , the @entity470 mutation status was assessed using both Py and Cy in 48 @entity1 : the median MAF of @entity9512 (MAFLR) was 18.5% (range: 8%-82%), and 45 @entity1 (94%) were identified as having an L858Rm using both Py and Cy. Three @entity1 (6%) with discrepant L858Rm findings were only identified using Py. The plotting of a receiver operating characteristic curve to identify the discordance in L858Rm findings showed that the area under the curve for MAFLR was 0.967 (95% confidence interval: 0.91-1) and that an MAFLR of 9% resulted in high sensitivity (100%) and specificity (99%). Also, 29 @entity1 with AELAd, excluding those with postoperative recurrences, had their @entity9512 status assessed using Cy or A. The median age, 69 years (range: 47-84 years); male/female, 14 (48%)/15 (52%); smokers/never-smokers 13 (45%)/16 (55%); ECOG PS 0-1/2-3, 26 (90%)/3 (10%); stage IIIB/IV, 4 (14%)/25 (86%); median MAFLR, 18% (range: 8%-63%). @entity1 with an MAFLR of  <=9% had a significantly shorter progression-free survival (PFS) period after TKI therapy than those with an MAFLR of >9% (mPFS: 92 versus 284 days, P = 0.0027). CONCLUSION: The MAF may be a potential predictive factor of TKI treatment efficacy in @entity1 with AELAd carrying the L858Rm.
