Author of

• 12409

  +

  P3.03 - Poster Session 3 - Technology and Novel Development (ID 152)

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

  • 12411

    +

    P3.03-002 - Heterogenity of Adeno carcinoma of Lung - change in Immunohistochemistry and histopathology chacter in patients treated with chemotherapy or EGFR-TKIs (ID 1356)

    09:30 - 09:30  |  Author(s): V. Agarwal
    • Abstract

    Background
    Adenocarcinoma of the lung is a heterogenous group of disease. Even within the same patient, the tumor may show, various patterns of histopathology. In fact published data suggest that only 1/3rd of lung cancer are homogenous. Although known this factor is not taken into account in treatment planning and management. It is also known that treatment induces heterogenity and change in character of the tumor.

    Methods
    46 patients of Stage IV Adenocarcinoma of Lung were studied. All patients were confirmed as Adenocarcinoma by doing IHC TTF p63. All slides were viewed by two pathologists and all patients had EGFR mutation done.IHC marker for neuro-endocrine differentiation was done i.e. Chromogranin-A and Synaptophysin. Patients were treated with chemotherapy or EGFR-TKI. Patients were re-biopsied on progression. The same set of IHC studies was done.

    Results
    

    	IHC marker for adenocarcinoma	IHC marker for squamous cell	Neuro-endocrine marker
    n=46
    Pre-chemotherapy/TKI	41 (89%)	15 (32%)	17 (37%)
    Post-chemotherapy/TKI	25 (54%)	25 (54%)	29 (63%)
    n=18
    Pre TKI	16 (89%)	5 (28%)	4 (22%)
    Post TKI	8 (44%)	9 (50%)	14 (78%)
    n=28
    Pre-chemotherapy	25 (89%)	10 (36%)	13 (46%)
    Post-chemotherapy	17 (61%)	16 (57%)	15 (54%)

    Median duration of chemotherapy - 10 months Median duration of TKI - 16 months Change in character on IHC - seen in approximately 30% patients Infact change in post TKI occurring in upto 50% of patients with gain in Small Cell characters. Of the 50% patients who gained i.e. 10 patients - 7 of them also showed microscopic features of Small Cell Carcinoma of Lungs.

    Conclusion
    The study suggests that patients with advanced lung cancer have benefit from chemotherapy and TKI. On treatment and on progression there is a change in IHC and histopathology character in the patients. It occurs in close to 40% in such patients. These changes also call for changes in treatment. Hence re-biopy in such patients is essential.