Non-inferiority of fragmented care for high-risk pediatric neuroblastoma patients: a single institution analysis.

Pediatric neuroblastoma (NB) patients receive multi-modal therapy and may experience care fragmented among multiple institutions with a significant travel burden, which has been associated with poor outcomes for some adult cancers. We hypothesized that fragmented care for pediatric NB patients is associated with inferior outcomes compared to treatment consolidated at one location. We reviewed paper and electronic records for pediatric NB patients who received ≥1 hematopoietic stem cell transplant (HSCT) at Duke from 1990-2017. Fragmented care was defined by treatment at >1 institution and grouped by 2 institutions vs. 3+ institutions. Distances were calculated using Google Maps. To compare all care groups, we used Fisher's Exact and Kruskal-Wallis tests for demographic and treatment characteristics, Kaplan-Meier for unadjusted overall survival (OS), and Cox proportional hazards for factors associated with OS. Of 127 eligible patients, 102 (80.3%) patients experienced fragmented care, with 17 treated at 3+ facilities. Kaplan-Meier analysis did not associate fragmented care with increased mortality (log-rank p = 0.13). With multivariate analysis, only earlier diagnostic decade and greater distance to HSCT remained significantly associated with worsened OS. In this single institutional study, we found fragmented care did not impact overall survival. Worsened overall survival was associated with increased travel distance for HSCT and further research should aim to improve supportive processes for patients undergoing HSCT for high-risk neuroblastoma.

A tumor-intrinsic PD-L1/NLRP3 inflammasome signaling pathway drives resistance to anti-PD-1 immunotherapy.

An in-depth understanding of immune escape mechanisms in cancer is likely to lead to innovative advances in immunotherapeutic strategies. However, much remains unknown regarding these mechanisms and how they impact immunotherapy resistance. Using several preclinical tumor models as well as clinical specimens, we identified a mechanism whereby CD8+ T cell activation in response to programmed cell death 1 (PD-1) blockade induced a programmed death ligand 1/NOD-, LRR-, and pyrin domain-containing protein 3 (PD-L1/NLRP3) inflammasome signaling cascade that ultimately led to the recruitment of granulocytic myeloid-derived suppressor cells (PMN-MDSCs) into tumor tissues, thereby dampening the resulting antitumor immune response. The genetic and pharmacologic inhibition of NLRP3 suppressed PMN-MDSC tumor infiltration and significantly augmented the efficacy of anti-PD-1 antibody immunotherapy. This pathway therefore represents a tumor-intrinsic mechanism of adaptive resistance to anti-PD-1 checkpoint inhibitor immunotherapy and is a promising target for future translational research.