Cancer-associated immunodeficiency is seriously worsened by surgical
trauma. Short-term preoperative
interleukin-2 (IL-2)
immunotherapy abolishes postoperative immunodeficiency and can induce immunological control of the growth of
minimal residual disease.
Growth factors play an important role in oncological practice in treating
neutropenia (
G-CSF) or associated anaemia during
chemotherapy (
erythropoietin). Unfortunately,
lymphocytopenia is not considered a
biological marker with regard to survival. On the other hand, the role of the immune response to surgical
trauma has been emphasised by many surgeons, and to counteract it immune nutrition (
omega 3 fatty acid,
mRNA,
arginine) or thymic
hormone have been tried. We believe that the obvious method of counteracting postoperative
lymphocytopenia is the administration of the specific
growth factor for T lymphocytes, i.e.
IL-2. The aim of this study was to report on our experience with
IL-2 preoperative immunoactivation in
colorectal cancer and the long-term outcome of patients treated in comparison with a control group operated on without
immunotherapy. In order to obtain activated
lymphocytosis at the time of operation administration of
IL-2 (6 million I.U. twice daily subcutaneously) for 3 preoperative days is sufficient, starting 4 days before surgery. The inclusion/exclusion criteria were histologically documented
colorectal cancer, elective surgery, laparotomic surgery, no second tumour, age 20-80 years, no cardiovascular, hepatic or
renal failure. From June 1992 to December 2005, 67 patients were treated (Dukes B/C: 46/21) with
IL-2 immunotherapy. The clinical and
biological results were compared with those of a control group of 173 patients (Dukes B/C 114/59) operated on in the same period and recruited with the same criteria. Dukes stage-C patients in both groups underwent
adjuvant chemotherapy plus
radiotherapy for
rectal cancer. Data were statistically analysed using Fisher's exact test, Student's T-test and analysis of variance, as appropriate. The overall survival curves were plotted with the Kaplan-Mayer method. After a median follow-up of 69 months (range: 12-169) the progression rate was 15/67 (22%) vs 68/173 (39%) in controls (p = 0.02). Important results were obtained in Dukes-B patients: progression rate 7/46 (15%) vs 37/114 (32,4%) in controls (p = 0.03). We can conclude that
immunotherapy is well tolerated.
IL-2 is capable of counteracting surgery-induced immunodeficiency. The amplification of the immune response in the post-operative period is capable of controlling
minimal residual disease after radical surgery, of reducing the progression rate, and of improving the prognosis and overall survival.