Author of

• 11866

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  P2.18 - Poster Session 2 - Pathology (ID 176)

  • Event: WCLC 2013
  • Type: Poster Session
  • Track: Pathology
  • Presentations: 1
  • Moderators:
  • Coordinates: 10/29/2013, 09:30 - 16:30, Exhibit Hall, Ground Level

  • 11870

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    P2.18-004 - Clinical application of immunocytochemical detection of ALK rearrangement on cytology slides for detection or screening of lung adenocarcinoma (ID 353)

    09:30 - 09:30  |  Author(s): T. Morimoto
    • Abstract

    Background
    Immunohistochemical screening of anaplastic lymphoma kinase (ALK) rearrangement has been regarded essential and routinely carried out to select the treatment for lung adenocarcinoma. However, due to difficulty to approach a tumor by transbronchial lung biopsy (TBLB), it often fails to obtain tumor tissues whereas tumor cells are contained in cytology specimens simultaneously obtained when the bronchoscopy is done. Therefore we evaluated the expression of ALK protein by using immunohistochemistry (IHC) on TBLB specimens and immunocytochemistry (ICC) on brushing smear cytology slides in the same cases, and compared the concordance rate of IHC and ICC results. ICC was carried out on routine Papanicolaou-stained slides after cytology diagnosis and decolorization.Background: Immunohistochemical screening of anaplastic lymphoma kinase (ALK) rearrangement has been regarded essential and routinely carried out to select the treatment for lung adenocarcinoma. However, due to difficulty to approach a tumor by transbronchial lung biopsy (TBLB), it often fails to obtain tumor tissues whereas tumor cells are contained in cytology specimens simultaneously obtained when the bronchoscopy is done. Therefore we evaluated the expression of ALK protein by using immunohistochemistry (IHC) on TBLB specimens and immunocytochemistry (ICC) on brushing smear cytology slides in the same cases, and compared the concordance rate of IHC and ICC results. ICC was carried out on routine Papanicolaou-stained slides after cytology diagnosis and decolorization.

    Methods
    IHC was done using the commercially available antibody against ALK (dilution 1:100, clone 5A4; Novocastra, Newcastle, UK), and signals were detected using the EnVision FLEX Mini-kit (Dako, Tokyo, Japan). Papanicolaou-stained bronchoscopic brushing smear cytology slides containing cells cytologically diagnosed as adenocarcinoma were used. ICC was carried out by using the same antibody and the detection kit as used in IHC. IHC and ICC expressions were quantified by three cytopathologists. Cytoplasmic ALK expressions were quantified using a three-value intensity score (0, 1+, 2+) and the intensity scores 1+ and 2+ are defined positive.

    Results
    Eighteen patients with adenocarcinoma were extracted in the Hirosaki University Hospital and the Hirosaki National Hospital. IHC and ICC results showed a very high concordance rate: sensitivity of ICC in comparison with IHC was 85.7% (6/7), specificity was 100% (11/11), positive predictive value was 100% (6/6), and negative predictive value was 91.6% (11/12).

    Conclusion
    Detection of ALK rearrangement using ICC on routine Papanicolaou cytology slides is considered to be advantageous for lung cancer treatments.