A Nature Communications study mapped genetic variation across complement cascade genes and found associations with pancreatic cancer susceptibility and prognosis. The multi-omic analysis integrated genomics with functional annotations to identify variants that modulate complement activation and tumor–immune interactions. Authors report specific alleles that correlate with altered complement expression in tumor tissue and with patient survival metrics, suggesting the complement system contributes to both tumorigenesis and disease trajectory. Functional follow-up implicated complement-related immune remodeling in the tumor microenvironment. Clinical implications include potential stratification markers for patient risk and exploratory therapeutic opportunities: complement-targeted agents could modulate tumor immunity in selected molecular subgroups, though clinical testing is required.