Background: Chronic subcutaneous rIL-2 at low doses produces long-lasting immunomodulatory effects and is considered an effective treatment for renal cell carcinoma with marginal activity in malignant melanoma and colorectal cancer.
Patients and methods: In this study we evaluated, by Minnesota Multiphasic Personality Inventory (MMPI), the psychological changes induced by rIL-2 in 10 patients with advanced tumors.
Results: After 3 months of rIL-2 treatment, 80% of the patients had a significantly increased score on the clinical scale of depression (D) and psychasthenia (Pt) (p<0.01), 70% on the scale of conversion hysteria (Hy) and 60% on the scales of schizophrenia (Sc) and psychopathic deviate (Pd), (p<0.05). These MMPI changes were however not paralleled by disease progression or clinical-overt psychological disease.
Conclusion: These findings demonstrate that low-dose rIL-2 is a psychoactive treatment, which deserves psychological monitoring The MMPI is feasible for the evaluation of subclinical psychological modifications induced by cytokine immunotherapy.