Immunotherapy in pancreatic cancer - current status and future.

Abstract

In pancreatic cancer, multimodal protocols, involving chemotherapy, radiation, or regional treatment, are initiated to improve oncological outcome. Since pancreatic adenocarcinoma has been shown to be susceptible to immune stimulation, several immunotherapy approaches have been investigated to define the role of immunotherapy in pancreatic cancer. A review of current and past data concerning experimental and clinical immunotherapy in pancreatic cancer is presented in the context of basic immunotherapeutic principles. Past pitfalls and future developments are analyzed and a synthesis of immune stimulation and immune suppression is deduced on the basis of published data. Preclinical and initial clinical studies with monoclonal antibodies CO17-1A, BW494/32 and anti-epidermal growth factor receptor (EGFR) have been conducted, and various targets suitable for immunotherapy have been identified involving new molecular and gene technology. Targets on pancreatic cancer cells currently under investigation are mucins (MUC-1), glycoproteins (GA733), ras peptides and EGFRs. Side effects are minor and rarely auto-immune reactive. Another approach combines randomized regional with systemic chemoimmunotherapy (mitomycin C, 5-fluorouracil, folinic acid, carboplatin, epirubicin; interferon-gamma, interleukin-2) in nonresectable pancreatic cancer and obtains significant differences in median survival rates (14 months vs 4.5 months in controls) and quality of life. Although single remarkable improvements in the immunological approach to treatment of pancreatic cancer have been made, immunotherapy in pancreatic cancer is still experimental. On the basis of reliable preclinical data, new immunotherapy protocols will have to be evaluated clinically. Careful monitoring of immune responses and side effects, and assessment of quality of life will ensure identification of effective immunotherapy protocols for human pancreatic cancer in the near future.