P2.16-002 Adequacy of Lymph Node Sampling during Lobectomy in a Small Community Teaching Hospital

Abstract

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-1negative 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.