Cancer immunohistogram representing cancer-immunity cycle by immunohistochemistry predicts the efficacy of immune checkpoint inhibitors in urological cancer patients

We developed an immunohistogram representing an individual cancer-immunity cycle based on immunohistochemical analyses. We evaluated its ability to predict the efficacy of immune checkpoint inhibitors (ICI) in 11 patients with urothelial carcinoma and 7 patients with renal cell carcinoma who underwent surgery and received ICIs for disease recurrence. Immunohistochemical analyses for CD8, TIA-1, HLA class I, HLA-DR, and PD-L1 were performed and scored 0–3. T-cell infiltration pattern was classified into desert, excluded, partially inflamed, and inflamed. Tumors with an inflamed or partially inflamed pattern and positive scores (score ≥ 1) for all five immune markers were classified as “immune-hot” and others as “immune-cold.” Association between the immunohistogram and ICI treatment efficacy was evaluated with objective response rate, disease control rate (DCR), progression-free survival (PFS), and cancer-specific survival (CSS). Eight (44%) and 10 (56%) patients had immune-hot and immune-cold tumors, respectively. Immune-hot tumors showed a higher DCR (100% vs. 40%, p < 0.01), longer PFS (median unreached for hot, 1.3 months for cold, p < 0.01), and longer CSS (median unreached for hot, 3.3 months for cold, p < 0.01) than immune-cold tumors. The immunohistogram could be clinically useful as an accessible biomarker for precision cancer immunotherapy in urological cancer.