Virtual Library

Start Your Search

Likun Chen



Author of

  • +

    P1.13 - Targeted Therapy (Not CME Accredited Session) (ID 945)

    • Event: WCLC 2018
    • Type: Poster Viewing in the Exhibit Hall
    • Track:
    • Presentations: 1
    • Moderators:
    • Coordinates: 9/24/2018, 16:45 - 18:00, Exhibit Hall
    • +

      P1.13-08 - Distribution, Differences in Clinical Characteristics and Resistance Mechanism of ALK Variants in Chinese Lung Cancer Patients. (ID 13678)

      16:45 - 18:00  |  Author(s): Likun Chen

      • Abstract
      • Slides

      Background

      ALK rearrangements are established targetable drivers in NSCLC. Recent reports indicate differential progression-free survival to ALK inhibitors according to specific EML4-ALK variant.

      a9ded1e5ce5d75814730bb4caaf49419 Method

      A total of 172 unique Chinese lung cancer patients with tumors harboring ALK rearrangements (ALK+) were enrolled in the study from 2016 to 2018. ALK+ were detected by Ventana, FISH, or next-generation sequencing based ER-Seq method, which enables simultaneously assess single-nucleotide variants, insertions/deletions, rearrangements, and somatic copy-number alterations across at least 59 genes (59-1021). Tissue biopsy was the first choice for NGS mutation profiling, and ctDNA or pleural effusion testing was used as an alternative.

      4c3880bb027f159e801041b1021e88e8 Result

      Of these 172 cases, the median diagnosis age was 50 (range 24-78), 58% were female, 90% was NSCLC. Of the 147 ALK+ cases detected by NGS, we identified 65 (44%) EML4-ALK v1 (E13; A20), 18 (12%) EML4-ALK v2 (E20; A20), 43 (29%) EML4-ALK v3 (E6; A20), 13 (9%) other EML4-ALK, and 8 (5%) non-EML4-ALK rearrangements. 2 new fusion genes were found in non EML4-ALK rearrangements (SRBD1-ALK (EX20; EX20) and CLIP4-ALK (EX9; EX20)), and the CLIP4-ALK patient’s tissue was also ALK positive by Ventana. V1 found a higher proportion of pleural effusion at baseline than non-v1 (12% v.s.5%). Mutation profiling by NGS were performed after disease progression in 55 patients treated with crizotinib. mPFS was 8.1 months, no significant difference existed between v1 and v3 (P=0.69). But the presence of known ALK resistance mechanisms was significantly higher in v3 as compared to non-v3 (67% v.s. 27%, P=0.038).

      8eea62084ca7e541d918e823422bd82e Conclusion

      Next generation sequencing allows for detection of the specific ALK fusion partner and variants, increases the understanding of the biology of ALK+ NSCLC, and may have value to foretell potential mechanisms of resistance.

      6f8b794f3246b0c1e1780bb4d4d5dc53

      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.

  • +

    P2.01 - Advanced NSCLC (Not CME Accredited Session) (ID 950)

    • Event: WCLC 2018
    • Type: Poster Viewing in the Exhibit Hall
    • Track:
    • Presentations: 1
    • Moderators:
    • Coordinates: 9/25/2018, 16:45 - 18:00, Exhibit Hall
    • +

      P2.01-117 - Concurrent Gene Alterations in Treatment-Naïve EGFR-Mutant Advanced Non-Small Cell Lung Cancer (ID 13102)

      16:45 - 18:00  |  Author(s): Likun Chen

      • Abstract
      • Slides

      Background

      EGFR-TKIs is the standard first line treatment for EGFR-mutant advanced non-small-cell lung cancer (NSCLC). However, 20% to 30% of patients who receive EGFR-TKIs exhibit primary resistance. The gene alterations in treatment-naïve EGFR-mutant advanced NSCLC should be better explored.

      a9ded1e5ce5d75814730bb4caaf49419 Method

      We retrospectively reviewed gene test results of 980 treatment-naïve advanced NSCLC samples in our institute. Tumor biopsy, ctDNA, pleural effusion or cerebrospinal fluid samples were analyzed using hybridization capture-based NGS ER-seq method, white blood cells as control, which enables simultaneously assess single-nucleotide variants (SNV), insertions/deletions (indel), rearrangements and somatic copy-number(CNV) variation at least 59 genes (range 59-1021 genes).

      4c3880bb027f159e801041b1021e88e8 Result

      Three hundreds and eighty one cases with EGFR sensitive mutation were identified, 358 adenocarcinoma, 7 squamous cell carcinoma, 1 adenosquamous carcinoma and 15 NSCLC. Among the patients, 88 patients (23.1%) harbored concurrent actionable mutations with EGFR, which 43 were exon 19 deletion, 37 were L858R and 8 were uncommon EGFR mutations. One patient had co-occurring L858R, T790M and CDKN2A frameshift mutation. The actionable mutations were from 23 genes, which involved in cellular signaling pathways, and some genes had been reported associated with EGFR-TKIs resistance (details in table). Except the actionable mutations, TP53 mutations were detected in 225 samples (59.1%, 225/381), which 35.1% (79/225) in exon8. Bcl-2–like 11(BIM) deletion were detected in 31 (8.1%, 31/381) white blood cells.

      Signaling Pathways

      Concurrent gene alterations

      Frequency(N=88)

      Cell cycle*

      CDKN2A

      3.9%

      CDK4

      2.1%

      CCNE1

      0.8%

      CCND1

      0.8%

      CCND3

      0.3%

      PI3K/AKT/mTOR*

      PIK3CA

      2.9%

      PTEN

      1.3%

      TSC1/2

      1.0%

      AKT2

      0.3%

      NF1

      0.3%

      RTKs*

      MET

      0.8%

      HER2

      0.8%

      FGFR2

      0.3%

      FGFR3-TACC3

      0.3%

      Ras/Raf/MAPK*

      KRAS

      0.8%

      Homologous Recombination Repair pathway

      BRCA2(sc+gm)

      0.8%

      BRCA1(sc)

      0.5%

      ATM

      0.5%

      PALB2

      0.3%

      Others

      CTNNB1

      2.9%

      MDM2

      2.4%

      SMARCA4

      0.8%

      JAK2

      0.5%

      sc, somatic mutation;

      gm, germline mutation;

      *, genes had been reported associated with EGFR-TKIs resistance

      8eea62084ca7e541d918e823422bd82e Conclusion

      Concurrent gene alterations in treatment-naïve EGFR-mutant advanced NSCLC is common, and mutiple genes are involved. This maybe contribute to the primary resistance to EGFR-TKIs in EGFR-mutant advanced NSCLC. Indicate the importance of multiplex molecular test and further researches of target therapies.

      6f8b794f3246b0c1e1780bb4d4d5dc53

      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.

  • +

    P2.06 - Mesothelioma (Not CME Accredited Session) (ID 955)

    • Event: WCLC 2018
    • Type: Poster Viewing in the Exhibit Hall
    • Track:
    • Presentations: 1
    • Moderators:
    • Coordinates: 9/25/2018, 16:45 - 18:00, Exhibit Hall
    • +

      P2.06-39 - Next Generation Sequencing Reveals Genetic Landscape of Malignant Mesothelioma (ID 12702)

      16:45 - 18:00  |  Author(s): Likun Chen

      • Abstract
      • Slides

      Background

      Malignant mesothelioma (MM) is a rare form of cancer affecting the mesothelium lining. The 5-year survival rate of advanced patients is less than 1% due to the lack of effective medical therapies. To investigate the possibility of targeted therapy for MM patients, a deeper understanding of the genetic basis is required.

      a9ded1e5ce5d75814730bb4caaf49419 Method

      We reviewed 26 samples taken from 22 MM patients who underwent genetic testing at our institute from 2016 to the present. Somatic mutation profiles were analyzed using hybridization capture based next-generation sequencing (NGS), which enables the simultaneous detection of single-nucleotide variants, insertions/deletions, rearrangements, and copy-number alterations of at least 59 genes (range 59 – 1021 genes).

      4c3880bb027f159e801041b1021e88e8 Result

      The 26 samples included 8 tumor tissue samples, 17 blood samples and 1 ascetic fluid sample. The most frequently mutated genes were TP53 (11/21), followed by NF2 (6), RB1 (4), NF1 (3), FLT1 (3), BAP1 (2), EGFR (2), FAT2 (2), FGFR4 (2), KIT (2), MAP3K1 (2), MLL4 (2), STK11 (2), APC, ATR, BRAF, BRCA2, CDKN2A, ERBB3, FBXW7, MET, KRAS, PIK3CA and so on. Among these mutations, 5 of NF2 mutations and 2 of NF1 mutations were loss-of-function mutations, which suggests the possible sensitivity of mTOR inhibitors administration. Besides, patients with the active or inactive mutations of KRAS, BRAF, CDKN2A, ERBB3, MET and PIK3CA gene might be sensitive to corresponding targeted drugs. MET exon 14 skipping mutation, commonly identified in non-small-cell cancer (NSCLC) patients, had never been reported in MM patients before. c-Met inhibitors such as crizotinib and cabozantinib may be of efficacy for this patient. Apart from predicting therapeutic effectiveness of MEK inhibitors, the detection of KRAS activating mutation may also provide prognostic information.

      8eea62084ca7e541d918e823422bd82e Conclusion

      NGS can identify genetic mutations comprehensively and provide predictive and prognostic implications for MM patients. It is a cost-effective tool to describe the genetic landscape of MM, which will facilitate the development of novel therapeutics for the treatment of MM patients.

      6f8b794f3246b0c1e1780bb4d4d5dc53

      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.

  • +

    P3.12 - Small Cell Lung Cancer/NET (Not CME Accredited Session) (ID 978)

    • Event: WCLC 2018
    • Type: Poster Viewing in the Exhibit Hall
    • Track:
    • Presentations: 1
    • Moderators:
    • Coordinates: 9/26/2018, 12:00 - 13:30, Exhibit Hall
    • +

      P3.12-12 - Genomic Profiling of Pulmonary Large-Cell Neuroendocrine Carcinoma (LCNEC) Reveals Distinct Mutational Landscape (ID 13244)

      12:00 - 13:30  |  Author(s): Likun Chen

      • Abstract
      • Slides

      Background

      The controversial classification of lung neuroendocrine tumor has been amended a few times since recognised as a separate entity. LCNEC shares clinical features with small cell lung carcinoma (SCLC) and they were both classified as lung neuroendocrine carcinoma according to the 2015 WHO lung primary pathology classification, numerous studies have revealed barely satisfactory outcomes when it was treated as SCLC. However the underlying molecular basis for such commonalities and discrepancies are poorly understood. In this study, we interrogated the genomic landscape of LCNEC and SCLC along with their histologically related subtypes: carcinoids and atypical carcinoids to define the molecular pattern of LCNEC.

      a9ded1e5ce5d75814730bb4caaf49419 Method

      We performed targeted sequencing in 35 tissue samples using a panel covering 520 cancer related genes, spanning 1.6MB of human genome, with an average sequencing depth of 1,418x. Among them, 15 were diagnosed with SCLC, 9 with LCNEC, 6 with carcinoid and 5 with atypical carcinoid.

      4c3880bb027f159e801041b1021e88e8 Result

      On average, LCNEC exhibited 13.5 mutations per million base pairs (Mb) and a C:G>A:T transversion rate of 34%, which is indicative of tobacco exposure. LCNEC had SCLC (16.7 Mb) had comparable TMB (p=0.18), which is significantly higher than carcinoids (1.2/Mb, p<0.001) and atypical carcinoids (2.4/Mb, p<0.001). The most frequently mutated gene in LCNEC is TP53 (89%, 8/9), followed by NOTCH1 (33%), KEAP1 (22%), RB1 (22%) and a few chromatin modifiers, including KMT2D (33%), KMT2C (33%). Co-mutation in TP53 and RB1, a hallmark of SCLC, was found in 22% (2/9) of LCNEC patients; in contrast, 80% of SCLC patients harbored concurrent mutation. 67% carcinoid (4/6) and 20% (1/5) atypical carcinoid patients had no mutation identified from this panel. No classic lung adenocarcinoma driver mutations were found in any subtype. Copy number analyses revealed significantly higher copy number variation (CNV) in SCLC and LCNEC comparing with carcinoids and atypical carcinoids, which yield virtually no CNV. Our analysis revealed a comparable CNV status of SCLC and LCNEC (p=0.158), with an enrichment in amplification of chromatin modifiers.

      8eea62084ca7e541d918e823422bd82e Conclusion

      Our study, comprehensively characterized 4 subtypes of neuroendocrine tumors, revealed a high TMB and CG:AT transversion rate in LCNEC patients as well as a distinctive mutation landscape, with an enrichment of mutations occurring at chromatin remodelers. Furthermore, LCNEC has comparable TMB and CNV status as SCLC, which are significantly higher than carcinoid and atypical carcinoids.

      6f8b794f3246b0c1e1780bb4d4d5dc53

      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.