Abstract 220: Intra-tumor immune heterogeneity is associated with prognosis of oropharyngeal head and neck squamous cell carcinoma

As cell-cell interactions among tumor and immune cells are known to contribute to tumor progression, in depth evaluation of tumor-immune heterogeneity will enable biomarker-guided patient stratification and improvement of treatment response. Here we examined head and neck squamous cell carcinomas (HNSCC) to reveal the prognostic significance of leukocytes in tumors with regards to their complexity, effector status and spatial characteristics via multiplex immunohistochemistry and image cytometry. To accomplish this, we examined oropharyngeal HNSCC (N = 38), where lymphoid, myeloid, and hypo-inflamed leukocyte complexity correlated with HPV-status (Tsujikawa et al. Cell Reports, 2017). In the present study, quantitative analysis of cell density and distribution of 14-distinct immune cell lineages (e.g., CD8 + T cells, regulatory T cells, Th1, Th2, Th17, Th0 lymphocytes, B cells, NK cells, CD163 + and CD163 - macrophages, mature and immature dendritic cells, mast cells, granulocytes) was analyzed via immune cell density mapping and tissue segmentation algorithms. We revealed tropism of polarized Th1-type cells within tumor nests versus stroma in HPV-associated HNSCC. In addition, Cox regression analysis of cell density and distribution of the 14 immune populations revealed that CD66b + granulocyte infiltration within tumor nests reflected a negative prognostic indicator for HNSCC outcome. Furthermore, cell-cell proximity analysis in HPV-associated HNSCC further revealed a correlation between PD-L1 positive immune cells, and micro-regionally polarized immune characteristics biased towards Th1, coincident with high density of CD8 + T cells. These results reveal intra-tumor immune heterogeneity is associated with micro-regional immune complexity profiles, and provide insight into in situ immune characteristics that may aid patient stratification for immune therapy going forward. Acknowledgement: This project was supported by the Japan Society for the Promotion of Science Grant-in-Aid for Young Scientists (Start-up, 17H07016), Oregon Clinical and Translational Research Institute (OCTRI), grant number (UL1TR000128) from the National Center for Advancing Translational Sciences (NCATS) at the National Institutes of Health (NIH), and P30 CA069533-17 OHSU Knight Cancer Institute. LMC acknowledges support from the NIH/NCI, DOD BCRP Era of Hope Scholar Expansion Award, Susan G. Komen Foundation, Stand Up To Cancer - Lustgarten Foundation Pancreatic Cancer Convergence Dream Team Translational Research Grant, Breast Cancer Research Foundation, and the Brenden-Colson Center for Pancreatic Health. Citation Format: Takahiro Tsujikawa, Guillaume Thibault, Young Hwan Chang, Edward El Rassi, Daniel R. Clayburgh, David Sauer, Akihito Arai, Molly F. Kulesz-Martin, Motomi Mori, Shigeru Hirano, Paul W. Flint, Lisa M. Coussens. Intra-tumor immune heterogeneity is associated with prognosis of oropharyngeal head and neck squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 220.