Table 3.

Analysis of plasma samples of follow-up cases

Patient codeTumor samplePlasma samples collected before commencement of treatmentPlasma samples collected during or after treatment*Time after TKI treatment commenced (wk)Response to TKI treatment
MutationMutant percentageMutationMutant concentration (copies/mL)MutationMutant concentration (copies/mL)
(A) Cases without pretreatment plasma samples
    Case 1Del1947NAND30SD
    Case 2Del1953NAND32PR
    Case 7L858R33NAND54PR
    Case 9Del199.8NAND20PR
    Case 12L858R44NAND4PR
(B) Cases with pretreatment plasma samples
Case 8L858R40L858R3.2ND60PR
Case 15L858R19L858R55L858R5526PD
Case 26L858R62L858R8,300L858R10014PR
Case 38L858R39L858R34,000L858R784CR
Case 39L858R26L858R9.7ND8PR
  • NOTE: Clinical response was defined by Response Evaluation Criteria in Solid Tumors. CR, complete response; PR, partial response; SD, stable disease; PD, progressive disease. Cases 1, 2, 7, 9, and 12 had no pretreatment plasma samples. NA, not applicable. All cases, except case 9, had gefitinib treatment. Case 9 had erlotinib treatment. Del19 denotes deletion in EGFR exon 19. ND, not detected. NA, not available. All L858R mutation are 2573T>G. All numerical figures are correct to two significant figures.

  • * Samples were collected during treatment, except for case 9. Erlotinib treatment was stopped in case 9, 4 wk before plasma collection.