Abstract
AIM: Interferons (IFNs) are known to have antiproliferative and immunoregulatory activities that are modulated through specific cell surface ligands, known as IFN-alpha, -beta, and -gamma receptors. The presence of these receptors and their impact on response to adjuvant therapy in patients with pancreatic cancer has not been determined. PATIENTS AND METHODS: Slides were prepared from 46 patients with pancreatic adenocarcinoma. Immunohistochemistry (IHC) was subsequently used to determine the expression of IFN- alpha/beta receptor-chain 2 (IFN-alpha/betaR) and IFN-gamma receptor-chain 1 (IFN-gammaR). The correlation between IFN receptor expression, tumor characteristics, and the overall patient response to adjuvant therapy were determined analytically. RESULTS: The IHC performed for pancreatic adenocarcinoma demonstrated a high IFN-alpha/betaR expression in 4% (2/46) of patients, moderate expression in 20% (9/46) of patients, and faint or no expression in 76% (35/46) of patients. IHC confirmed a high expression of IFN-gammaR in 52% (24/46) of patients, moderate expression in 35% (16/46) of patients, and faint or no expression in the remaining 13% (6/46) of patients. Thirty-two (69.7%) patients received adjuvant therapy. Clinicopathological survey did not demonstrate any significant correlation between IFN-alpha/betaR and IFN-gammaR expression with regard to tumor size, vascular invasion, perineural invasion, lymph node metastases, or stage of disease. Use of adjuvant therapy was associated with increased survival in patients with IFN-alpha/betaR-positive tumors compared with patients with IFN-alpha/betaR-negative tumors (24 months versus 14.7 months in log rank test, p=0.012). The expression of IFN-gammaR, however, had no impact on patient survival (20 months vs 17 months; p=0.656, log rank test). CONCLUSION: IFN-alpha/betaR is associated with improved survival for patients with resectable pancreatic cancer who received adjuvant therapy.