The Immunogenomic Landscape of Neuroendocrine Prostate Cancer

Purpose: Patients with neuroendocrine prostate cancer (NEPC) are often managed with immunotherapy regimens extrapolated from small cell lung cancer (SCLC). We sought to evaluate the tumor immune landscape of NEPC compared to other prostate cancer types and SCLC. Experimental Design: In this retrospective study, a cohort of 170 patients with 230 RNA sequencing and 104 matched whole exome sequencing data were analyzed. Differences in immune and stromal constituents, frequency of genomic alterations, and associations with outcomes were evaluated. Results: In our cohort, 36% of the prostate tumors were identified as CD8+ T-cell inflamed, while the remaining 64% were T-cell depleted. T-cell inflamed tumors were enriched in anti-inflammatory M2 macrophages and exhausted T-cells and associated with shorter overall survival relative to T-cell depleted tumors (HR=2.62, p