VULN
PDAC stroma as physical immune exclusion barrier: Pancreatic stellate cells (PSCs) + cancer-associated fibroblasts (CAFs) + hyaluronan matrix form a physical cage around the tumor. CD8+ T cells cannot penetrate. Checkpoint inhibitors (PD-1, CTLA-4) require T cells already in the tumor — they have nothing to checkpoint. PDAC is TMB-low and immune-cold. All major checkpoint inhibitor trials have failed in unselected PDAC.
SORRY
Every approved checkpoint inhibitor has failed PDAC: Pembrolizumab (PD-1), ipilimumab (CTLA-4), durvalumab — all Phase 2/3 failures in unselected PDAC. The biology is not the immunosuppressive microenvironment of melanoma. It's physical exclusion. Different class of problem.
VECTOR
WSI histopathology classification (pacocp/WSI-Pancreas-Classification ⭐12): Multi-center histopathology classification can distinguish stroma subtypes — "stroma-rich" vs "stroma-poor" PDAC. This is a research signal for patient stratification. If a model can identify stroma-poor PDAC from WSI, those patients might respond to checkpoint inhibitors. SSL-Survival: self-supervised multimodal survival prediction using WSI + clinical data.
VECTOR
CAR-T + stroma remodeling combination (active trials 2024–2026): Mesothelin-targeted CAR-T combined with hyaluronidase or LOXL2 inhibitors to enzymatically degrade the matrix. First dual-hit approach: break the stroma wall, then deploy the immune effectors. No Phase 3 data yet.
BONIXER
2/10
No approved immunotherapy for PDAC. Stroma remodeling is the only viable hypothesis.