Immunological studies in a patient with the glucagonoma syndrome

The glucagonoma syndrome is a rare clinical entity characterized by a glucagon-producing tumor of the pancreas, necrolytic migratory erythema, weight loss and usually decreased glucose tolerance. Lately there has been increasing interest in the interaction of peptide hormones and the immune system, implicating a regulatory role of the peptide hormones on immune activation and function. We present a patient with metastasizing glucagonoma and highly elevated plasma levels of glucagon and pancreatic polypeptide. Normal numbers of peripheral blood lymphocytes with normal proportions of the T and B populations were seen. Within the T lymphocyte population the percentage of T4+ cells (helper phenotype) was increased with a concomitant decrease in T8+ cells (suppressor/cytotoxic phenotype), resulting in an abnormally high T4/T8 ratio of 6.7 (mean reference value 1.8). Functional tests demonstrated a normal tuberculin reaction and adequate lymphocyte responses in vitro to polyclonal activators. Furthermore we noticed a urine electrophoretic pattern consistent with a proximal tubular kidney defect. It is concluded that studying the immune system in patients with endocrine active pancreatic tumors may give clues on the influence of pancreatic peptide hormones on immune function and regulation.