Author of

• 20179

  +

  P2.15 - SCLC/Neuroendocrine Tumors (ID 716)

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

  • 23530

    +

    P2.15-015 - Negativity for Thyroid Transcription Factor 1 Was Correlated with Less Neuroendocrine Differentiation in Small Cell Lung Cancers (ID 9180)

    09:30 - 09:30  |  Author(s): K. Mizumura
    • Abstract

    Background:
    The biological and clinical significance of thyroid transcription factor 1 (TTF-1) remains unclear in small cell lung cancer (SCLC). The purpose of this study was to clarify the clinicopathological characteristics of TTF-1-negative SCLC.
    
    Method:
    We retrospectively studied the associations between survival and the expression of TTF-1, and examined the association between the expression of TTF-1 and neuroendocrine markers (Synaptophysin, Chromogranin, and CD56), neuroendocrine cell-specific transcription factor (ASCL1, BRN2), and NF1B, which is an oncogene for SCLC. Formalin fixing and paraffin embedding (FFPE) and clinical data in SCLC patients were collected and used. The study was approved by the institutional review board.
    
    Result:
    Thirty-five patients were examined. Eleven patients were negative for TTF-1, and twenty-four patients were positive for TTF-1. The analysis demonstrated that overall survival was not statistically significant between patients with TTF-1-negative and those with TTF-1-positive SCLC. However, frequency of negativity of Synaptophysin and Chromogranin was greater in patients with TTF-1-negative SCLC than in those with TTF-1-positive SCLC based on immunohistochemical expression, and the difference was statistically significant. mRNA expression of ASCL1, NF1B, and serum ProGRP were significantly lower in patients with TTF-1-negative SCLC than in those with TTF-1-positive SCLC. We showed that TTF-1-negative SCLC showed less neuroendocrine differentiation. It is suspected that TTF-1-positive and -negative SCLC have different biological characteristics.
    
    Conclusion:
    TTF-1-negative SCLC was different in terms of aspects of neuroendocrine differentiation (negativity of Synaptophysin and Chromogranin, lower expression of ASCL1 and NF1B) compared to TTF-1-positive SCLC.