Hormonal and metabolic effects of chronic interleukin-2 infusion in cancer patients

Interleukin-2 (IL-2) is secreted during the immune response to trauma, sepsis, and transplant rejection. Its role in the development of the metabolic abnormalities observed in these circumstances is not well defined. We studied the clinical, hormonal, and metabolic response to a 5-day IL-2 infusion (3 x 10(6) U/m2/day) of nine patients with metastatic renal carcinoma. IL-2 induced systemic manifestations after a latent period of 4 h (fever, tachycardia) or 8 h (hypotension). These manifestations persisted until the end of the infusion. Insulin levels were not modified. Among the stress hormones, cortisol increased at the onset of fever and tachycardia, whereas the rise in catecholamines occurred later (24 h) and appeared more as a response to the development of hypotension. The only metabolic effects observed were a late (third day) rise of lactate and a late and transient (third to fourth day) decrease of glycerol and nonesterified fatty acids. These metabolic modifications were temporally related to the development of hypotension and result more likely from low tissue perfusion rather than from a direct or hormone-mediated effect of IL-2.