Serum Immunoglobulin G Is Associated With Decreased Risk of Pancreatic Cancer in the Swedish AMORIS Study
Sam Sollie, Aida Santaolalla, Dominique S. Michaud, Debashis Sarker, Sophia N. Karagiannis, Debra H. Josephs, Niklas Hammar, Göran Walldius, Hans Garmo, Lars Holmberg, Ingmar Jungner, Mieke Van Hemelrijck
Abstract
Background: Emerging evidence points to potential roles of the humoral immune responses in the development of pancreatic cancer. We evaluated associations between pre-diagnostic serum markers of the humoral immune system (immunoglobulin A (IgA), immunoglobulin G (IgG) and immunoglobulin M (IgM)), and pancreatic cancer risk in the Swedish Apolipoprotein-related MORtality RISk (AMORIS) study. Methods: We selected all participants (≥20 years old) with baseline measurements of IgA, IgG or IgM (n= 41900, 136221, and 29919, respectively). Participants were excluded if they had a history of chronic pancreatitis and individuals were free from pancreatic cancer at baseline. Multivariate Cox proportional hazards regression was used to estimate risk of pancreatic cancer for medical cut-offs of IgA, IgG and IgM. Results: Compared to the reference level of 6.10-14.99 g/L, risk of pancreatic cancer was elevated among those with IgG levels <6.10 g/L [HR: 1.69 (95% CI 0.99-2.87)], and an inverse association was observed among those with IgG levels ≥15.00 g/L [0.82 (95% CI 0.64-1.05); Ptrend = 0.027]. The association appeared to be stronger for women than men [HR: 0.64 (95% CI 0.43-0.97) and 0.95 (95% CI 0.69-1.29) respectively]. No associations were observed with IgA or IgM. Conclusion: An inverse association was observed between pre-diagnostic serum levels of IgG and risk of pancreatic cancer. Our findings highlight the need to further investigate the role of immune response in pancreatic cancer aetiology.