Immunosuppression and human cancer: Role of prostaglandins

Prostaglandins, unsaturated fatty acid derivatives with diversified pharmacologic activity, have been implicated in the pathophysiology of many diseases. Prostaglandin E (PGE) levels were measured by radioimmunoassay in the plasma of 41 normocalcemic patients with various stages of malignancies. Delayed hypersensitivity was assessed by a battery of six recall skin test antigens (ST) and by Dinitrochlorobenzene (DNCB) sensitization and challenge. Twenty‐five patients with one or more positive skin tests had a mean PGE level of 87 ± 8 pg/ml, whereas 16 patients with negative ST had a mean PGE level of 96 ± 12 pg/ml. Twenty‐one DNCB negative patients had a mean PGE level of 98 ± 12 pg/ml and eight totally anergic patients had a mean PGE of 96 ± 12 pg/ml. All PGE values were within the normal range and there was no statistical difference between the four groups, (p < 0.1). We concluded that circulating PGE does not correlate with the non‐specific immunosuppression seen in cancer patients.