Therapeutic response of untreatable hepatocellular carcinoma after application of the immune modulators IL-2, BCG and melatonin.

AIM: Application of immunotherapy to a patient with untreatable hepatocellular carcinoma. CASE REPORT: The patient had a tumor of 60 mm in the liver. The pathological anatomic diagnosis was adenoma. However, after surgery of the tumor seven new lesions arose, showing that the original tumor had been a hepatocellular carcinoma. In addition, when hepatocellular adenomas grow to a size of more than 6-8 cm, they are considered cancerous and thus become a risk for hepatocellular carcinoma. The patient was treated with interleukin-2, Bacillus Calmette Guerin, and melatonin. RESULTS: During treatment, the alpha-fetoprotein levels in blood fell from 5,000 IU/ml to zero, at which level it remained during the follow-up period of two years. No tumor was detectable on MRI and CT. Six years after the diagnosis of untreatable hepatocellular carcinoma, the patient remains in a good condition. CONCLUSION: In this case, combined immunomodulating therapy was effective. For patients with metastasized tumors of the liver who are not suitable for conventional therapy, immunomodulation may delay tumor progression, induce tumor regression, or even be curative in some patients. Immunotherapeutic approaches combined with conventional methods for hepatocellular carcinoma treatment may be able to improve therapeutic efficacy.

Local therapy of cancer with free IL-2.

This is a position paper about the therapeutic effects of locally applied free IL-2 in the treatment of cancer. Local therapy: IL-2 therapy of cancer was originally introduced as a systemic therapy. This therapy led to about 20% objective responses. Systemic therapy however was very toxic due to the vascular leakage syndrome. Nevertheless, this treatment was a break-through in cancer immunotherapy and stimulated some interesting questions: Supposing that the mechanism of IL-2 treatment is both proliferation and tumoricidal activity of the tumor infiltrating cells, then locally applied IL-2 should result in a much higher local IL-2 concentration than systemic IL-2 application. Consequently a greater beneficial effect could be expected after local IL-2 application (peritumoral = juxtatumoral, intratumoral, intra-arterial, intracavitary, or intratracheal = inhalation). Free IL-2: Many groups have tried to prepare a more effective IL-2 formulation than free IL-2. Examples are slow release systems, insertion of the IL-2 gene into a tumor cell causing prolonged IL-2 release. However, logistically free IL-2 is much easier to apply; hence we concentrated in this review and in most of our experiments on the use of free IL-2. Local therapy with free IL-2 may be effective against transplanted tumors in experimental animals, and against various spontaneous carcinomas, sarcomas, and melanoma in veterinary and human cancer patients. It may induce rejection of very large, metastasized tumor loads, for instance advanced clinical tumors. The effects of even a single IL-2 application may be impressive. Not each tumor or tumor type is sensitive to local IL-2 application. For instance transplanted EL4 lymphoma or TLX9 lymphoma were not sensitive in our hands. Also the extent of sensitivity differs: In Bovine Ocular Squamous Cell Carcinoma (BOSCC) often a complete regression is obtained, whereas with the Bovine Vulval Papilloma and Carcinoma Complex (BVPCC) mainly stable disease is attained. Analysis of the results of local IL-2 therapy in 288 cases of cancer in human patients shows that there were 27% Complete Regressions (CR), 23% Partial Regressions (PR), 18% Stable Disease (SD), and 32% Progressive Disease (PD). In all tumors analyzed, local IL-2 therapy was more effective than systemic IL-2 treatment. Intratumoral IL-2 applications are more effective than peritumoral application or application at a distant site. Tumor regression induced by intratumoral IL-2 application may be a fast process (requiring about a week) in the case of a highly vascular tumor since IL-2 induces vascular leakage/edema and consequently massive tumor necrosis. The latter then stimulates an immune response. In less vascular tumors or less vascular tumor sites, regression may require 9-20 months; this regression is mainly caused by a cytotoxic leukocyte reaction. Hence the disadvantageous vascular leakage syndrome complicating systemic treatment is however advantageous in local treatment, since local edema may initiate tumor necrosis. Thus the therapeutic effect of local IL-2 treatment is not primarily based on tumor immunity, but tumor immunity seems to be useful as a secondary component of the IL-2 induced local processes. If local IL-2 is combined with surgery, radiotherapy or local chemotherapy the therapeutic effect is usually greater than with either therapy alone. Hence local free IL-2 application can be recommended as an addition to standard treatment protocols. Local treatment with free IL-2 is straightforward and can readily be applied even during surgical interventions. Local IL-2 treatment is usually without serious side effects and besides minor complaints it is generally well supported. Only small quantities of IL-2 are required. Hence the therapy is relatively cheap. A single IL-2 application of 4.5 million U IL-2 costs about 70 Euros. Thus combined local treatment may offer an alternative in those circumstances when more expensive forms of treatment are not available, for instance in resource poor countries.

Changes in cytokine profile during local IL-2 therapy in cancer patients.

BACKGROUND: Exogenous interleukin 2 (IL-2) can influence the complex cytokine network in vivo. This study investigated the cytokine profile of patients with different malignancies before and after local IL-2 administration. PATIENTS AND METHODS: The human TH1 / TH2 cytometric bead array (CBA) kit was used to investigate IL-2, IFNgamma, TNFalpha, IL-4, IL-5 and IL-10 in a control group and in 13 patients. RESULTS: The baseline serum IL-4 levels in patients were lower than in healthy controls, while the baseline ascitic IL-10 levels in patients was higher than in serum. The IL-2 applications induced a strong serum increase in IL-2 and IL-5 and even more in ascites, while IL-10 increased weakly and mainly locally. One month after the start of therapy, the serum IFNgamma had increased in patients, reaching the level of the control group. CONCLUSION: After local injection, IL-2 probably leaks into the blood circulation. The higher increases of IL-2, IL-5 and IL-10 in ascites compared to the serum suggests that the injected cytokines and their effects are mainly local. The minor increase of the immunosuppressive IL-10 could explain the therapeutic difference between local and systemic IL-2 therapy since IL-10 levels markedly increase after systemic IL-2 therapy. IL-5 was always increased after IL-2 therapy and, consequently, may be a downstream mediator of antitumour responses.

Locoregional IL-2 low dose applications for gastrointestinal tumors.

AIM: To explore the feasibility of local interleukin 2 (IL-2) in patients with different forms of abdominal cancer. This required experimentation with the time interval between IL-2 applications and the methods of application. METHODS: Sixteen patients with stages III and IV of gastrointestinal malignancies (primary or metastatic) who were admitted to our Department of Gastroenterology were treated with locoregionally applied IL-2 in low doses. RESULTS: No major problems applying locoregional IL-2 were encountered. In 6 out of 16 patients, a modest but clinically worthwhile improvement was obtained. Adverse effects were minimal. The therapeutic scheme was well tolerated, even in patients in a poor condition. CONCLUSION: This study demonstrates the feasibility of low dose locoregional IL-2 application in advanced abdominal cancer. Local IL-2 therapy gives only negligible adverse effects. The results suggest that it is important to apply intratumorally. Local IL-2 may be given adjunct to standard therapeutic regimes and does not imply complex surgical interventions. These initial results are encouraging.