In:
Journal of Clinical Oncology, American Society of Clinical Oncology (ASCO), Vol. 30, No. 15_suppl ( 2012-05-20), p. 10596-10596
Abstract:
10596 Background: Anti-EGFR inhibitors are superior to chemotherapy in first-line therapy of advanced EGFR-mutant NSCLC. The EURTAC trial was a randomized Phase III trial of erlotinib vs. chemotherapy in patients with EGFR-mutant NSCLC. Interim results showed significant improvement in progression-free survival (R. Rosell, ASCO 2011). An accurate rapid in vitro diagnostic for EGFR mutations is needed to select patients for this therapy. Methods: Prospective EGFR mutation testing for the trial was performed on laser-capture microdissected tumor cells using a combination of 3 lab-developed tests (LDTs), including a Length Analysis of Fluorescently-labeled PCR (Genescan) method for exon 19 deletions, a Taqman-based PCR assay for exon 21 mutation with laser-capture macrodissected tumor cells, and secondary Sanger sequencing. A subset of samples from the trial was retrospectively tested with an AS-PCR assay (cobas EGFR mutation test) which detects L858R and 〉 29 exon 19 deletions. The test provides automated results within 8 h; the DNA required can be isolated from one 5-micron tissue section. Four methods were compared: AS-PCR assay, LDT, direct Sanger sequencing and massively parallel sequencing (MPS; 454, Branford, CT). Results: LDT results were obtained for 1044 screened patients. Residual tumor blocks were available for 487 patients (47%), including 303 wild-type, 172 mutant (135 enrolled on the trial) and 12 inconclusive cases by the LDT. Comparison of AS-PCR and LDT results showed a positive percent agreement (PPA) – 93.7% (CI 88.8%, 96.5%), and negative percent agreement (NPA) – 97.5% (94.9%, 98.8%). Comparison of AS-PCR and Sanger results showed a PPA of 96.6% (91.7%, 98.7%) but an NPA of 88.3% (84.1%, 91.5%). Among 34 AS-PCR + /Sanger - case, MPS confirmed the presence of exon 19 deletions in 25 cases and L858R mutations in 7. Direct comparison of AS-PCR and MPS results showed a PPA of 93.1% (88.1%, 96.1%) and NPA of 97.7% (95.0%, 98.9%). Clinical outcomes for cases with mutations detected by the AS-PCR test will be presented. Conclusions: The AS-PCR assay was highly concordant with the LDT and MPS, and more sensitive than Sanger sequencing.
Type of Medium:
Online Resource
ISSN:
0732-183X
,
1527-7755
DOI:
10.1200/jco.2012.30.15_suppl.10596
Language:
English
Publisher:
American Society of Clinical Oncology (ASCO)
Publication Date:
2012
detail.hit.zdb_id:
2005181-5
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