Abstract 4036: Prognostic value of infiltrating immune cell profiling in lung adenocarcinoma

Abstract

Abstract Neoplastic cancer cells and cancer stroma (including infiltrating immune cells) determine the biology and prognosis of cancer. Various types of adaptive and innate immune cells are known to infiltrate the cancer stroma. However, the patterns and spatial distribution of immune cell infiltration as well as their association with tumor histology remain poorly understood. To address these issues, we comprehensively analyzed the infiltrating immune cells present in lung adenocarcinoma. The principal types of both adaptive and innate infiltrating immune cells were immunohistochemically evaluated in the predominant histological components of 111 lung adenocarcinomas. The same analysis was also carried out on 143 samples of histological subtypes making up more than 20% of tumors. As a result, plasma cells and B cells with interfollicular distribution were almost exclusively observed in invasive histological subtypes, while increased number of mast cells were observed in noninvasive histological subtypes. Cluster analysis revealed four distinct immunosubtypes: those characterized by high CD8/CD3 ratios with low stromal cellularity (CD8 subtype), those with increased mast cell numbers (mast cell subtype), those with increased macrophage/DC infiltration with variable amounts of T cell infiltration (mϕ/DC subtype), and those with increased plasma cell infiltration in addition to increased macrophage/DC infiltration and variable increases in other infiltrating immune cells (T cells, Tregs, pDCs, and neutrophils) (plasma cell subtype). These immunosubtypes correlated with histological subtypes. Univariate and multivariate analyses identified the plasma cell subtype as an independent negative prognostic factor. Furthermore, we found that these plasma cells may be one of the major producers of immunosuppressive cytokine IL-35 in cancer stroma. Consequently, comprehensive immunohistochemistry-based profiling of infiltrating immune cells has potential as a powerful method for analyzing the cancer stroma of various cancer tissues. Citation Format: Yutaka Kurebayashi, Katsura Emoto, Yuichiro Hayashi, Ikuo Kamiyama, Takashi Ohtsuka, Hisao Asamura, Michiie Sakamoto. Prognostic value of infiltrating immune cell profiling in lung adenocarcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4036.