Start Your Search
OA10 - EGFR Mutations (ID 382)
- Event: WCLC 2016
- Type: Oral Session
- Track: Biology/Pathology
- Presentations: 1
OA10.07 - Report on Liquid Biopsies from Advanced Lung Adenocarcinoma Patients and Correlation with Their Tumor Biopsy Profiles (ID 4826)
11:00 - 12:30 | Author(s): C. Marana
Liquid biopsy (LBx) has emerged as an alternative tool for the management of advanced lung cancer patients (pts) identifying driver mutations, and hence, improving personalized medicine. There are still controversial issues such as standardization, validation of different technologies, concordance with tissue molecular profile results (TMPR), and others. LBx offers many advantages including non-invasive, bypass tumor heterogeneity, an opportunity for serial measurements to evaluate response or early recurrence, and others.
Guardant 360 was analyzed in 100 consecutive stage IV or recurrent lung adenocarcinoma (adeno) pts. Guardant 360 is a panel of 70 genes including single nucleotide variations, amplifications, translocations, and short insertions/duplications/deletions in exons 19 and 20 of the EGFR, and others. Cell-free DNA (cfDNA) is extracted from plasma and genomic alterations are analyzed by massively parallel sequencing of amplified target genes. TMPRs from each subject was obtained or recovered for comparison with their LBx counterparts. TMPRs from this cohort was developed in different CLIA laboratories
69 pts were females; median age 72 (range, 27-99). 84/100 pts had at least 1 genomic alteration by LBx (range, 1-10). Most common abnormalities found in LBx were: TP53 (37 pts), EGFR (35 pts), NF1 (20 pts), KRAS (12 pts), MET (14 pts). From this 84 pts with + LBx results, 67 pts (80%) had TMPRs for comparison. Main reason for lack of TMPRs: insufficient tumor (19/100; 19%). For comparison between the 2 modalities, we considered all pts with available results in both tests; hence, 81 pts were used to compare tumor biopsy (TBx) vs. LBx. 37 pts out of 81 (46%) had at least 1 similar genomic abnormality found in both TBx and LBx, respectively. Most of the concordance was in EGFR alterations (19/28; 68%). LBx caught 16 additional EGFR genomic aberrations not being identified by TBx. A total of 35 EGFR genomics aberrations were identified in LBx; 16/35 EGFR mutations found in LBx were actionable and 5 of these 16 actionable EGFR mutant cases were only found in LBx not in TBx.
LBx offers an alternative to identify genomic alterations. Still, insufficient tumor is the major reason for lacking of TMPRs. EGFR mutations are the most common actionable mutations found in LBx; also, it has a high correlation with TBx (68%). LBx identified more gene abnormalities than TBx, and in some cases, the actionable EGFR mutations were found only in LBx sample.
Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.