Author of

• 20167

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  P2.03 - Chemotherapy/Targeted Therapy (ID 704)

  • Event: WCLC 2017
  • Type: Poster Session with Presenters Present
  • Track: Chemotherapy/Targeted Therapy
  • Presentations: 1
  • Moderators:
  • Coordinates: 10/17/2017, 09:30 - 16:00, Exhibit Hall (Hall B + C)

  • 23324

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    P2.03-053 - A Five-Year Audit of EGFR and ALK Testing at a Tertiary Care Centre in North India: More Sensitive Methods Do Make a Difference! (ID 10427)

    09:30 - 09:30  |  Author(s): A. Bal
    • Abstract

    Background:
    Detection of targetable driver mutations in NSCLC may depend on the method employed. We carried out an audit to determine whether the EGFR mutation (EGFR-M) and ALK rearrangement (ALK-R) detection rate is dependent upon on the testing method used. We also sought to assess if EGFR-M and ALK-R was associated with baseline demographic characteristics.
    
    Method:
    Retrospective analysis of NSCLC patients who underwent testing for EGFR-M and ALK-R from January 2012 till May 2017. Methods used for EGFR-M were Real time ARMS PCR and gene sequencing while Break Apart FISH and D5F3 immunohistochemistry(IHC) were used for ALK-R testing.
    
    Result:
    Of the 599 patients tested for EGFR-M, 541 (90.3%) had interpretable results with an overall prevalence of 21.4%(n=116). Real time ARMS-PCR and gene sequencing yielded 95.9% and 81.9% interpretable results respectively. ALK-R testing was done in 462 patients of whom 431 (93.3%) had interpretable results, of which 8.6%(n=37) were positive. D5F3 IHC and Break Apart FISH yielded 94.7% and 82% interpretable results respectively. Mean age was 59.2 and 54.0 years respectively for EGFR-M and ALK-R patients with 54.3% and 45.1% being females. Mutations in exon 19 were the most common (n=81, 69.8%) followed by exon 21 L858R (n=30, 25.9%). 87/116 (75%) and 19/37 (51.4%) of EGFR-M and ALK-R patients received EGFR-TKIs and crizotinib respectively. Table shows differences in prevalence of EGFR-M and ALK-R prevalence in relation to gender, smoking status, histology and testing method used.

    Table 1 Smoking, gender and histologic profile of the patients tested for EGFR mutations and ALK rearrangements

    	EGFR-M positive (n=116)	ALK-R positive (=37)
    Overall	21.4%	8.6%
    Adenocarcinoma only	23.8%	9.5%
    Females vs. males	37.1% vs. 14.3%	12.5% vs. 6.8%
    Non-smokers vs. smokers	34.6% vs. 11.9%	11.6% vs. 6.5%
    Female non smokers	39.9%	12.4%
    Male non-smokers	26.1%	10.5%
    Male smokers	11.1%	6.3%
    Females with adenocarcinoma	40.7%	13.3%
    Method used for testing	23.1% Real time ARMS PCR vs. 17.8% gene sequencing	9.0% D5F3 IHC vs. 4.9% Break Apart FISH

    
    
    Conclusion:
    Real time ARMS-PCR and D5F3 IHC are more sensitive methods for detecting EGFR-M and ALK-R respectively. Prevalence of a targetable driver in North Indian NSCLC patients ranges from 52.3% amongst female non-smokers to 17.4% of male smokers which are very encouraging results from both the patients and the treating oncologists perspectives. Higher percentage of EGFR-M patients receive targeted therapy as compared to ALK-R.