Combination therapy with interleukin-2 and alpha-interferon for the treatment of patients with advanced cancer

Cardiotoxicity as a dose-limiting factor in a schedule of high dose bolus therapy with interleukin-2 and alpha-interferon. An unexpectedly frequent complication

BACKGROUND

In a group of patients with metastatic melanoma treated with high dose immunotherapy, there was an unexpectedly high incidence of severe cardiac adverse effects.

METHODS

Sixteen patients with metastatic melanoma were treated with high dose interleukin-2 (IL-2) and alpha-interferon (alpha-IFN). Each treatment cycle consisted of IL-2 at a dose of 12 MIU/m2 and alpha-IFN at a dose of 3 MIU/m2, given as intravenous bolus injections every 8 hours on Days 1-5, every 3 weeks for a total of three cycles. Before treatment, careful cardiologic screening was performed, including electrocardiogram (ECG), stress test, cardiac multiple uptake-gated acquisition (MUGA) scan, and echocardiography. During therapy, patients were monitored with daily ECG and creatine phosphokinase measurements. Once cardiac damage was suspected, IL-2 and alpha-IFN were discontinued, and echocardiography, stress test and MUGA-scan were repeated. If indicated, cardiac catheterization with endomyocardial biopsies was performed.

RESULTS

Despite pretreatment cardiac screening, seven patients (44%) exhibited myocardial injury. Acute myocardial infarction occurred in one patient, cardiomyopathy developed in four, asymptomatic ECG changes appeared in one, and 1 patient died of acute cardiac arrest. Echocardiography showed hypokinesis and decreased left ventricular ejection fraction. These abnormalities disappeared within 6 months. Cardiac catheterization in four affected patients revealed normal coronary arteries, but endomyocardial biopsies showed interstitial edema, vacuolation, and degeneration of myocytes. Electron-microscopic examination showed fragmentation of myofibrils, swelling of mitochondria and loss of mitochondrial cristae.

CONCLUSIONS

This intensive treatment schedule of IL-2 and alpha-IFN is prohibited by severe and life-threatening cardiac toxicity.

Enhanced therapeutic effects of anti-tumour agents against growth and metastasis of colon carcinoma 26 when given in combination with interferon and interleukin-2

Chemoimmunotherapy of pulmonary metastases was investigated in a protocol of combined anti-tumour agents and interferon-beta and/or interleukin-2. The combination of interferon-beta and interleukin-2 after treatment with etoposide or cisplatin exerted profound therapeutic effects in an experimental model (lung colonization) using colon carcinoma 26, which was resistant to interferon-beta or to interleukin-2 alone. Cured mice treated with anti-tumour agents and cytokines rejected re-implanted tumours. Moreover, this approach also had profound effects on spontaneous pulmonary metastases, together with the effect on primary tumours. However, this combination of cytokines did not enhance the anti-tumour activity of etoposide in athymic mice with pulmonary metastases. Injections of tumour-bearing BALB/c mice with a combination of etoposide and these cytokines resulted in a marked increase in CD8+, asialo-GM1+ cells. Thus the combined treatment with interferon-beta and interleukin-2 after administration of cytotoxic drugs may induce specific anti-tumour immunity, and such combinations may offer a new approach to the development of effective therapy for cancer metastases.

Immunotherapy in liver tumours: I. Combined administration of recombinant interleukin-2 (IL-2) and interferon-alpha through the subcutaneous transposed spleen prolongs the half-life of IL-2 in vivo and enhances antitumor effects

Two modifications in this study, including the use of subcutaneous transposed spleen (STS) as a port for administration of recombinant interleukin-2 (IL-2) and interferon-alpha (IFN-alpha), and the mixture of IL-2 and IFN-alpha with degradable starch microspheres (IIM), for the treatment of rat liver tumor are introduced. Group I is the control. Group II received the IIM schedule through the STS. Group III and group IV received IL-2 and IFN-alpha, diluted with normal saline and injected through the STS or a peripheral vein. The comparative studies indicated that the best result was seen in group II where the elevated concentration of IL-2 in portal blood and massive tumor necrosis with lysis were observed. Inhibitions of tumor growth of 33%, 20% and 13% in group II, III, and IV, respectively, were observed. We conclude that administration of the IIM schedule through the STS is an effective method for the treatment of liver tumor in rats.

Vaccination with anti-idiotype antibodies mimicking a renal cell carcinoma-associated antigen induces tumor immunity

We have previously isolated and characterized 6 different internal image mouse monoclonal anti-idiotype antibodies (Ab2) directed against the paratope of mouse monoclonal antibody G250 (MAbG250, Ab1), which specifically reacts with human renal cell carcinoma (RCC). These Ab2s (NUH31, 44, 51, 71, 82 and 91) demonstrated specificity for the combining site of Ab1, and appeared to recognize 2 partly overlapping idiotopes on Ab1. In this study, we further characterize the fine specificity of the Ab2, investigate whether the immunogenicity of Ab2 could be enhanced by conjugation to a carrier and investigate the anti-tumor efficacy of Ab3 sera in mice challenged with RCC. Immunization of animals with Ab2 conjugated to keyhole limpet hemocyanin as carrier protein resulted in a 2-fold increase in antigen-specific anti-anti-idiotype antibodies (Ab3) as compared with immunization using Ab2 alone. Specific reactivity was observed with antigen-positive cell lysates, and all Ab3 sera contained immunoglobulin resembling Ab1 (Ab1'), as shown by competitive Ab1-antigen binding assays. Fine-specificity studies of Ab3 sera revealed that the Ab2s can be divided into 4 mutually exclusive groups, showing that the 6 Ab2s recognize 4 slightly different idiotopes in the Ab1 binding pocket. Treatment of RCC-challenged mice with Ab3 sera resulted in significant tumor growth inhibition and lower tumor take rates as compared with control groups. Ab3 sera obtained from NUH-91-immunized animals showed superior characteristics as compared to the other Ab3 sera: no tumors remained after 5 weeks of Ab3-NUH91 treatment. Our findings indicate that the Ab2 elicit powerful anti-tumor effects in immune-competent animals.

A phase II study of advanced colorectal cancer patients treated with combination 5-fluorouracil plus leucovorin and subcutaneous interleukin-2 plus alpha interferon

Twenty-one patients with advanced, pretreated colorectal cancer in disease progression were entered in a phase II study to investigate the use of 5-fluorouracil (5FU) + leucovorin with subcutaneous Interleukin-2 + alpha interferon (alpha-IFN). Eighteen of these patients were evaluable for response to treatment: 1 partial response (PR) (duration 8 months), 9 stable disease (SD) (median duration of 6.5 months, range 2-15) and 8 progressive disease (PD). The PR patient survived for 15 months, the SD patients for a median of 11 months and 8 months for PD patients. Toxicity evaluated in the 21 patients reached grade 4 for mucositis in two cases. Grade 3 toxicity was observed more frequently for fever (52.3%) and diarrhea (33.3%) and was most probably the result of the combined side-effect of chemotherapy and the biological response modifiers (BRMs). Treatment was, for the most part, carried out on an out-patient basis as originally planned. In 15 patients tests were carried out to verify whether any immuno-activation had taken place. Significant increases were found during the course of therapy regarding cluster of differentiation activation (HLA-DR, CD71, CS25). Different curves were observed during the course of treatment with respect to the CD8 value, which proved higher in SD patients than in PD patients. Our study would seem to suggest that the addition of BRMs to 5FU + leucovorin could increase survival. The next step, however, must be to determine lower doses of IL-2 for subcutaneous administration in order to reduce toxicity but maintain the same immunostimulation.

Subcutaneous low-dose recombinant interleukin 2 and alpha-interferon in patients with metastatic renal cell carcinoma

A double-institution phase II study was performed in patients with metastatic renal cell carcinoma treated subcutaneously (s.c.) with interleukin 2 (IL-2) and alpha-interferon (INF-alpha). Thirty-eight patients were treated over a course of 7 weeks. Initially (day 1 + 2) patients received s.c. IL-2 at 18 x 10(6) IU m-2. During the following 6 weeks, patients received s.c. IL-2 at 3.6 x 10(6) IU m-2 for 5 days per week and s.c. INF-alpha at 5 x 10(6) for 3 days per week. Thirty-eight patients were evaluated for response. An objective response was seen in seven patients (18.4 +/- 12.3%), with one complete response and six partial responses. Median duration of response was 6.7 months. Toxicity could be evaluated in 38 patients and was limited. Mild to moderate toxicity included fever (97%), fatigue or malaise (76%), nausea or vomiting (50%), anorexia (32%), hypotension (26%), neurological disturbances (26%) and hypercreatininaemia (39%). In addition, four grade IV haematological toxicities were noted. No cardiac side-effects were seen. IL-2 and INF-alpha given by this schedule can be safely administered in an outpatient setting. The objective response rate was similar to our previous treatments with high-dose IL-2 given as a continuous infusion.

A phase II study of combined administration of dacarbazine and carboplatin with home therapy of recombinant interleukin-2 and interferon-alpha 2a in patients with advanced malignant melanoma

Chemotherapy and interleukin-2 (IL-2) and/or interferon alpha (IFN alpha) produce objective responses in a proportion of patients with advanced malignant melanoma. The duration of response to chemotherapy is usually less than 4 months, and immunotherapy has resulted in long-lasting remissions in a small number of patients with metastatic melanoma. The current study was conducted to improve the antitumor efficacy and the interactions between recombinant (r) IL-2, rIFN alpha 2a and chemotherapy. A total of 16 evaluable patients with metastatic malignant melanoma were entered into a phase-II study designed to assess the response rate and therapeutic efficacy of dacarbazine and carboplatin followed by rIL-2 and rIFN alpha 2a. Patients received 750 mg/m2 dacarbazine with 400 mg/m2 carboplatin each by intravenous bolus on days 1 and 22. Recombinant IL-2 and IFN alpha 2a were administered on an outpatient basis (home therapy) subcutaneously for 6 consecutive weeks: 4.8 x 10(6) IU/m2 rIL-2 daily, 5 days a week; 6.0 x 10(6) IU/m2 rIFN alpha 2a thrice weekly. There were responses in 6 of the 16 enrolled patients with an overall response rate of 37.5% (95% confidence interval: 14%-61%). All responding patients had partial responses. The median survival time of the responding patients was significantly better than that of patients with progressive and stable disease (P = 0.03). The median duration of response was 11 months (range 2-24 months). Responses in lung, liver, soft tissue and lymph-node sites were noted.

Adjuvant therapies for cancer of the thoracic esophagus

During the past four decades, especially in recent years, various active adjuvant therapies combined with surgery have improved the outcome in cases of cancer of the esophagus. However, no optimum adjuvant therapy has been determined. From 1981 to 1992, 341 patients with regional and distant node metastasis who underwent curative surgery were treated with postoperative radiotherapy (RT), postoperative radiochemotherapy (RC), and postoperative aggressive chemotherapy (AGC) in a controlled study in our department of surgery. Five-year survival rates, including operative deaths and unrelated diseases of the former group, were 0% for RT, 19.9% for surgery alone, 39.8% for RC, and 48.2% for AGC. Such rates for the latter group were 6.8% for AGC, 13.3% for surgery alone, and 33.3% for RC. In addition, results of a group study on the effectiveness of three-field node dissection in 715 cases of thoracic esophageal carcinoma by 10 institutions were analyzed. This analysis showed that there were no differences in the 5-year survival rate of curative surgery in cases with positive nodes among the groups treated with surgery alone (SA), with postoperative radiotherapy (PR), and with postoperative chemotherapy (PC). As to the 91 cases with positive cervical nodes, the 3-year survival rates in cases treated with SA (n = 22), PR (n = 20), and PC (n = 49) were 25.3%, 48.1%, and 53.6%, respectively; a significant improvement of survival in these patients. Summaries of studies of preoperative or postoperative radiotherapy, and both multimodal therapies are introduced.

Follow up of soluble IL-2 receptor level in metastatic malignant melanoma patients treated by chemoimmunotherapy

Immunological parameters following chemoimmunotherapy combination were studied in 31 patients with metastatic malignant melanoma. They received Cisplatin (100 mg/m2) on day 1 and 28, recombinant IL-2 (rIL-2; Eurocetus) in continuous infusion from day 3 to 6, 17 to 21, 31 to 34 and 45 to 49. Interferon-alpha (IFN-alpha; Roche) was given subcutaneously three times weekly. No significant change in CD4/CD8 ratio at onset or during treatment was observed between responder (n = 19) and non-responder (n = 12) patients. Regarding the IL-2 receptor (IL-2R) study, the percentage of cells expressing Tac (p55) receptor did not change either for healthy volunteers (n = 20) and patients before any therapy, or between responder and non-responder patients. Concerning serum soluble IL-2R shedding before therapy, we observed a significant increase (P = 0.001) in patients (79 +/- 40 pM) compared with healthy donors (30 +/- 15 pM), but no significant variation was seen between responder and non-responder patients. In contrast, during the treatment, the soluble IL-2R level increased in both groups but, interestingly, a significant difference was found between responder and non-responder patients from day 7 (P < 0.05) to day 21 (P < or = 0.01), suggesting that the cells from non-responder may be slower in becoming stimulated. This finding is the most striking point of our study and suggests that sIL-2R might be an early predictive factor of the clinical response as obtained by logistic regression (P = 0.0063). Therefore patients with a serum soluble IL-2R level greater than 250 pM at day 21 have a 12-fold more chance of undergoing a clinical response.

Influence of various cytokines on the interleukin-2-dependent lysis of melanoma cells in vitro

To obtain information about useful combinations of various cytokines in melanoma therapy, we studied the influence of interleukin-2 (IL-2) in combination with interferon-alpha (IFN-alpha), IFN-gamma and tumour necrosis factor-alpha (TNF-alpha) on the lytic activity of IL-2-stimulated cells in vitro. Peripheral mononuclear cells (PMC) were incubated for 4 days with various combinations of cytokines and used as effector cells. Two different melanoma cell lines (M19 and M26) were used as target cells. The lytic activity of stimulated PMC was determined using a modified hexosaminidase assay. IL-2 was mainly responsible for the lytic activity of the effector cells in a dose-dependent manner. IFN-alpha, IFN-gamma and TNF-alpha did not enhance lytic activity with an optimal IL-2 dose (50 IU/ml IL-2). Using a suboptimal IL-2 dose (5 IU/ml), they increased cytotoxicity. The specific lysis of M19 cells was significantly increased by pretreatment of the cells with 5 IU/ml IFN-alpha together with 50 IU/ml TNF-alpha (t-test, P < or = 0.001), while the specific lysis of M26 cells was increased by pretreatment with 5 IU/ml IFN-gamma. We conclude that the lysis of melanoma cells by cytotoxic cells in vitro can be enhanced by various cytokines. The optimal cytokine combination differed for the two melanoma cell lines tested.

Relationship between soluble tumor necrosis factor (TNF) receptors and TNF alpha during immunotherapy with interleukin-2 and/or interferon alpha

Eleven metastatic cancer patients were studied during three different regimens of immunotherapy with interleukin-2 (IL-2) and/or interferon alpha (IFN alpha): group A received 4 days of IL-2 i.a. infusion (n = 3), group B IFN alpha s.c. during 5 days (n = 4), followed on day 3 by 5 days of a continuous IL-2 i.v. infusion, and group C had 4 days of IL-2 i.v. infusion together with s.c. IFN alpha on days 1 and 4 (n = 4). Soluble tumor necrosis factor receptors (sTNFR) p55 and p75 and TNF alpha concentrations in serum were analyzed before therapy and daily during 8 days of the first therapy cycle. sTNFR was measured by radioimmunoassay. sTNFR p55 increased in all patient groups from a baseline value of 5.2 +/- 0.9 ng/ml to a maximum of 13.6 +/- 1.2 ng/ml by days 3-4 (P = 0.003). sTNFR p75 increased from 7.6 +/- 1.1 ng/ml to peak values of 30.1 +/- 2.6 ng/ml in groups A and B (P = 0.02). In group C the sTNFR p75 response was weak (NS). In group B, the increase of both p55 and p75 occurred only after addition of IL-2 to IFN alpha. TNF alpha increased weakly during treatment with IFN alpha alone (group B); it rose strongly during IL-2 and the combined treatment (groups A-C) from 8 +/- 2 pg/ml to 115 +/- 13 pg/ml (P = 0.003). In group B, it reached the maximum 24 h after addition of IL-2 to IFN alpha and decreased thereafter. There was a significant relationship between TNF alpha and sTNFR p55 or sTNFR p75 in groups A and C, (P = 0.001), but not in group B. Group C was also investigated during the third therapy cycle. The increase of sTNFR p75 was stronger (P = 0.01) and that of TNF alpha weaker than in the first cycle; the sTNFR p55 response was similar in both cycles. In conclusion sTNFR p55 and p75 are rapidly induced during IL-2 and IL-2+ IFN alpha treatment, the increase of sTNF receptors parallels or exceeds that of TNF alpha and may influence the immunomodulatory effects of TNF alpha during cytokine therapy.

Treatment of advanced renal cell cancer with sequential intravenous recombinant interleukin-2 and subcutaneous alpha-interferon

Starting from in vitro studies suggesting synergistic antitumour activity against renal cell cancer (RCC) of recombinant interleukin-2 (rIL-2) and alpha-interferon (IFN), a phase II trial was initiated to test the clinical activity of this combination. The two cytokines were administered sequentially, with the aim of reducing the risk of additive toxicity and enhancing the immunological reaction against the tumour. The original treatment schedule consisted of rIL-2 18 x 10(6) U/m2/day by continuous intravenous infusion for 120 h days 1-5, and alpha-IFN 2b, at a flat dose of 9 x 10(6) U by subcutaneous or intramuscular injection thrice in a week, from day 8 to 28. Treatment was planned to be continued for six or more 28-day cycles, depending on clinical response. 12 patients were treated according to this schedule; as some cardiovascular toxicity was experienced in this set of patients, 11 further patients were treated with half-dose rIL-2 (i.e. 9 x 10(6) U/m2/day). 17 out of 23 enrolled patients completed at least one cycle of treatment and were evaluated for response. We observed six major responses [one complete response (CR) + five partial responses (PR)] for an objective response rate of 35% [95% confidence interval (CI) 17-59%]. 5 additional patients achieved stabilisation of disease; one of them reached CR after surgical extirpation of a lung mass. Sites of response included lung, nodes and bone. Duration of response is 12+ months for CR; 17, 16, 12+, 9 and 9 months for PRs. Median survival is 16 months. Response was not significantly different between full-dose and half-dose rIL-2. Considering stable disease (SD) as responses, there seemed to be a higher chance of response for patients with smaller tumour burden (P = 0.032). The toxicity of rIL-2 treatment, mainly cardiovascular, was substantial; 9 patients experienced severe cardiotoxicity, consisting of major arrhythmias, myocardial ischaemia, reduction of ejection fraction measured with heart radionuclide scan, and were excluded from continuing treatment. Other rIL-2-related toxicities forcing exclusion from the study were severe thrombocytopenia (1 case), and generalised exfoliative dermatitis requiring steroids (1 case). Otherwise, treatment was well tolerated; rIL-2-related toxicities promptly recovered after rIL-2 discontinuation in the majority of cases, and no treatment-related deaths were reported. The half-dose rIL-2 regimen was significantly less toxic in terms of hypotension (P = 0.014), fever (P = 0.014), oliguria (P = 0.042), serum creatinine elevation (P = 0.009) and prothrombin time elongation (P = 0.038).(ABSTRACT TRUNCATED AT 400 WORDS)

Phase I study of interleukin-2 combined with interferon-alpha and 5-fluorouracil in patients with metastatic renal cell cancer

Interferon-alpha (IFN-alpha) and interleukin-2 (IL-2) each has produced a 15%-20% response in metastatic renal cell cancer. Combining IFN-alpha with either IL-2 or 5-fluorouracil (5-FU) enhanced IFN-alpha activity. We have therefore conducted a Phase I Study combining IL-2, IFN-alpha, and 5-FU. The patients were continuously infused with IL-2 (1-3 x 10(6) u/m2) and 5-FU (600-750 mg/m2) for a 5-day period every 28 days, and IFN-alpha (4-5 x 10(6) u/m2) was injected subcutaneously daily. Lymphokine-activated killer (LAK) and natural killer (NK) cell activity was measured on days 0 and 8. Twenty-one patients received 76 courses. All primary tumors were controlled by surgery (81%) or angioinfarction. Hematologic toxicity was mild; median nadir of platelets was 117 K/microL and of granulocytes was 1.2 K/microL. Dose-limiting toxicity included mucositis, liver damage, and hypotension. No treatment-related death occurred, and only one patient required intensive-care-unit support. Two patients had an objective response, one of which was a complete response. Increased LAK cell and NK cell activity occurred at all IL-2 dose levels. Simultaneous delivery of IL-2, IFN-alpha, and 5-FU is safe and shows antitumor and biologic activity. 5-FU did not appear to suppress IL-2-induced LAK and NK cell activation. Maximum tolerated dose of the three-drug combination is IL-2, 2 x 10(6) u/m2, 5-FU 600 mg/m2, and IFN-alpha, 4 x 10(6) u/m2.

Treatment of chronic myelogenous leukemia with recombinant human interleukin-2 and interferon-alpha 2a

The safety, tolerance, and clinical effects of combined therapy with recombinant interferon-alpha (IFN-alpha) and interleukin-2 (rIL-2) administered subcutaneously for 2 courses of 4 weeks each, with 4 weeks interval between courses, given as outpatient therapy have been assessed in 10 patients with Philadelphia chromosome (Ph1)-positive chronic myelogenous leukemia (CML). All patients were previously treated with conventional chemotherapy and 3 failed to respond to IFN-alpha administered prior to our study. Median duration of disease from diagnosis was 36 months. Seven patients were in first chronic phase and the other 3 were in blast crisis, second chronic phase, and relapse post-bone marrow transplantation (BMT), respectively. Hematological response (median follow-up 16 months) was observed in 9 patients, with a decline in number of white blood cells and platelets. Elimination of Ph1 was observed in the patient who relapsed post-BMT with complete elimination bcr/abl RNA by polymerase chain reaction. Rebound lymphocytosis and eosinophilia were observed in most of the patients. Toxicity was acceptable. The main adverse effects were fever, chills, fatigue, anorexia, nausea, and vomiting. The side effects were reversible and no interruption of treatment was required. There was no treatment-related hospitalization or deaths. These data suggest that simultaneous subcutaneous IFN-alpha and rIL-2 home therapy is feasible, reasonably well tolerated, and potentially beneficial in CML patients. These observations may have important implications for the treatment of minimal residual disease following allogeneic and autologous marrow transplantation.

Immunotherapy of metastatic melanoma with interferon-alpha and interleukin-2: pattern of progression in responders and patients with stable disease with or without resection of residual lesions

This evaluation was performed in melanoma patients after successful immunotherapy to describe the pattern of relapse. 63 patients received interferon (IFN)-alpha and high-dose interleukin (IL)-2, resulting in three complete responses (CR), 13 partial responses (PR), three mixed responses (MR) and 17 stable diseases (SD). Median duration of response was 7 months (range 3-28) without surgery. Most relapses occurred at pre-existing sites. Duration of CR was 14-37+ months. In 11 patients, residual tumour lesions were resected. Interestingly, histology revealed almost complete tumour regression in 6 patients, including 2 of 4 with SD. 5 of these 11 patients have relapsed so far, 6 patients are still free of disease with a median of 17 months (range 8-34). Following relapse, 4 of 6 patients responded to retreatment with the identical IFN alpha/IL-2 protocol. The authors conclude that initial disease progression is mostly at previous sites of disease. Resection of residual lesions may offer a chance for extended disease-free survival similar to patients with CR to immunotherapy. Retreatment of relapsing patients is favourable.

Renal, metabolic, and hemodynamic side-effects of interleukin-2 and/or interferon alpha: evidence of a risk/benefit advantage of subcutaneous therapy

Systemic immunotherapy with recombinant interleukin-2 (rIL-2) via intravenous (i.v.) and subcutaneous (s.c.) administration produces objective responses in a proportion of advanced cancer patients. While most of the previous investigations chose the i.v. route for cytokine application, there is an increasing number of trials employing s.c. rIL-2 therapy. The comparison of reported response rates for i.v. versus s.c. therapy reveals no significant differences between these modalities. In an effort to describe systemic toxicities of s.c. cytokine therapy with regard to renal, metabolic, and hemodynamic abnormalities and to compare these effects to toxicities reported upon i.v. therapy, we retrospectively evaluated 148 treatment cycles of s.c. immunotherapy given to 107 outpatients. Our study cohorts consisted of 15 patients who received s.c. rIL-2 at doses of (4.8-14.4) x 10(6) IU m-2 day-1 5 days/week for a total of 8 weeks, 20 patients who received rIFN alpha 2b at (3.0-6.0) x 10(6) m-2 day-1 thrice weekly for a total of 6 weeks, and 72 patients who were given s.c. rILFN alpha 2b at 6.0 x 10(6) U/m2, three times per week, plus s.c. rIL-2 at (14.4-18.0) x 10(6) IU/m2 on days 1 and 2, followed by 4.8 x 10(6) IU m-2 day-1 5 days/week for 6 consecutive weeks. These treatment regimens were well tolerated in the outpatient setting; no toxic death occurred, and none of the patients developed life-threatening toxicity due to a capillary leak syndrome. Upon s.c. combination therapy, dyspnea at rest occurred in 6% of patients and grade III and IV hypotension occurred in 7% and 4%, respectively; plasma protein was significantly decreased (mean nadir +/- standard deviation, 67 +/- 5 g/l). In addition, s.c. therapy led to a significant increase in serum creatinine (mean peak +/- standard deviation, 115.1 +/- 21.4 mumol/l) and urea nitrogen (mean peak +/- standard deviation, 6.5 +/- 2.5 mmol/l); electrolyte disturbances and direct nephrotoxicity never caused major clinical symptoms. This was in marked contrast to a multitude of dose-limiting and life-threatening adverse reactions reported upon i.v. rIL-2 therapy. We conclude that palliative low to intermediate-dose s.c. rIL-2/rIFN alpha combination therapy, in contrast to i.v. treatment, can be administered in the ambulatory setting with good practicability and excellent safety. This outpatient regimen is as effective against metastatic renal cell cancer as the most aggressive i.v. rIL-2 protocol reported.

Daily alternating administration of high-dose alpha-2b-interferon and interleukin-2 bolus infusion in metastatic renal cell cancer. A phase II study

BACKGROUND

Both interleukin-2 (IL-2) and alpha-interferon (alpha-IFN) have some efficacy in renal cell cancer (RCC) as single agents. Additionally, there is some evidence for additive or synergistic antitumoral activity of IL-2 and alpha-IFN in vitro and possibly in vivo. Based on these data, the authors initiated a Phase II trial with a combination of recombinant IL-2 (rIL-2) and recombinant alpha-IFN (alpha-rIFN) in advanced RCC.

METHODS

Thirty-six assessable patients with metastatic RCC were entered in this Phase II trial using a daily alternating schedule of alpha-rIFN and rIL-2. Over a period of 14 days, the patients received daily alternating treatment with 10 x 10(6) IU/m2 of recombinant alpha-2b-interferon subcutaneously and 18 x 10(6) IU/m2 of rIL-2 as a 1-hour intravenous infusion. This treatment schedule was repeated every sixth week up to a maximum of four cycles. After the second cycle, patients were examined for response. Patients with stable disease or better received two additional cycles of therapy. Patients with progressive disease were available for other strategies.

RESULTS

Thirty-six patients entered the trial and were assessable for toxic effects. Thirty of 36 patients completed at least two cycles and were assessable for response. Nine patients achieved an objective response: 2 had complete responses (CR) and 7 had partial responses (PR). Three patients had a minor response. No effect was observed in patients with local relapse or bone metastases. A relapse-free survival length of 6 months or longer was seen in both patients with CR (12, 23 + months) and in four of seven patients with PR (6, 7, 12, 12 months). The toxicity was moderate and included fever and nausea in most patients, and hypotension, fatigue, skin rash, and arthralgia in a minority of the patients. No Grade 4 and only occasionally Grade 3 toxicity was observed. Fluid retention was negligible. The monitoring of immunologic parameters showed a significant rebound lymphocytosis including cytotoxic (CD56+) cells; in responders the peak of lymphocytosis occurred up to 1 week later than in nonresponders. Peripheral lymphocytes obtained after therapy showed only a slight increase of natural killer cell and lymphokine-activated killer cell activity. During therapy, there was a great release of secondary cytokines as tumor necrosis factor-alpha, gamma-interferon, and interleukin-6, with a peak level 2-4 hours after rIL-2 infusion.

CONCLUSIONS

In conclusion, daily alternating administration of alpha-rIFN and rIL-2 is effective in RCC with less toxicity, and the response rate is comparable to those of other immunotherapeutic schedules, including adoptive immunotherapeutic schedules, including adoptive immunotherapy and combinations of high-dose IL-2 and alpha-IFN.

Cytoreductive surgery prior to interleukin-2-based therapy in patients with metastatic renal cell carcinoma

From May 1985 to December 1990, 93 patients with the clinical diagnosis of metastatic renal cell carcinoma and their primary tumor in place were evaluated for cytoreductive surgery as preparation for systemic therapy with regimens based on interleukin-2. These patients had typical sites of metastatic disease and manifestations of paraneoplastic syndromes. Patients underwent removal of the primary tumor, as well as debulking when this could be performed safely. Thirty-two percent of patients (30/93) had a second surgical resection in addition to their nephrectomy, frequently because of the large size of the primary tumor and its invasion of adjacent structures. Thirteen percent of patients (12/93) experienced postoperative complications. There were no perioperative mortalities. Forty percent of patients (37/93) who underwent nephrectomy could not be treated with immunotherapy, usually because of progression of disease. A preoperative ECOG status greater than or equal to 2 was the only significant risk factor associated with failure to undergo immunotherapy (P = 0.043). The response rate to immunotherapy in the 56 patients receiving interleukin-2 was 27 percent (4 CR, 11 PR).

Cytokine combinations in immunotherapy for solid tumors: a review

The use of cytokines alone or in combination with other cytokines or cytotoxic drugs has had a profound effect upon widely metastatic disease in many cases. However, despite the encouraging results in early trials, there is much room for improvement. Few responses to these combinations are complete, and toxicity has in some cases been quite severe. Changes in dose, route, or schedule of administration of the drugs, or the development of cytokine analogs may lead to more efficacious and less toxic regimens. In addition, new cytokines such as interleukin(IL)-7 and IL-12 are currently under investigation for potential use in future immunotherapy trials. These prospects and the use of cytokine combinations are promising advances in the treatment of human cancer.

Low dose cyclophosphamide, alpha-interferon and continuous infusions of interleukin-2 in advanced renal cell carcinoma

Pretreatment with a low dose of cyclophosphamide (CY) has been claimed to inhibit suppressor functions and augment various immune functions. A combination of a low dose of CY, alpha-interferon (IFN-alpha) and continuous infusion of interleukin-2 (IL-2) was used to treat patients with advanced renal cell cancer (RCC) (stage IV). Sixteen patients received four cycles consisting of CY (500 mg m-2) three days prior to daily i.m. injections of alpha-IFN (3 x 10(6) U), and continuous infusion of 18 x 10(6) IU rIL-2 for five days. The cycle interval was three weeks. Two patients had partial response (13%) (26+ and 12+ months), two had a minor response (9+ and 4 months), and three patients achieved stable disease (19+, 14+ and 8+ months). No patients required intensive care. Side effects were mainly fever, malaise, capillary leak syndrome and diarrhoea. Non-responders showed significantly higher eosinophil and platelet counts compared to responders. Serum concentration of IL-2 was significantly higher in responders. 5/11 patients had abnormally low values of serum thyroxine after therapy. Two patients needed thyroid hormone substitution. The difference between the initial and the lowest thyroxine values correlated significantly to survival (p < 0.03). The addition of CY to rIL-2 and IFN-alpha in the present protocol did not contribute to an increased major response rate.

Interferon-alpha and interleukin-2 in the treatment of metastatic melanoma. Comparison of two phase II trials

BACKGROUND

Interferon-alpha (IFN alpha) and interleukin-2 (IL-2) are active agents against malignant melanoma. There is, however, no consensus on the optimal dosing schedule of both drugs. This is a report of two sequential immunotherapy trials in patients with metastatic melanoma using two different IL-2 dosing schedules.

METHODS

Schedule A consists of IFN alpha, 10 million U/m2/day subcutaneously for 5 days, followed by continuous intravenous infusion of IL-2, 1 mg/m2/24 hours for 5 days. Schedule B consists of the same dose of IFN alpha, but a modified regimen of IL-2. To improve the induction of high-affinity IL-2 receptors, the initial IL-2 dose was increased (1 mg/m2/6 hours, followed by 1 mg/m2/12 hours, and 1 mg/m2/24 hours). To reduce toxicity, the dose was reduced thereafter to 0.25 mg/m2/24 hours for the following 3 days. Both regimens were repeated after 4 weeks.

RESULTS

27 patients were treated with schedule A with a response rate of 18% (1 complete response [CR], 4 partial responses [PR]), 95% confidence interval, 6-36%. The response rate in 27 patients treated with schedule B was 41% (3 CR, 8 PR), 95% confidence interval, 22-61%. Severe, often dose-limiting toxicity was associated with IL-2 in schedule A, particularly hypotension and fluid retention. Toxicity was reduced significantly in schedule B. Maximal serum levels of soluble CD25 were 17,022 +/- 13,070 U/ml in schedule A, and 31,148 +/- 4227 U/ml in schedule B (P < or = 0.01). Serum levels of TNF alpha were significantly lower in schedule B than in schedule A, as were the side effects.

CONCLUSIONS

Toxicity of IL-2 is reduced by modifying the schedule of administration, which also enhances the immunologic response and appears to increase the response rate.

The management of isolated renal recurrence of renal cell carcinoma following complete response to interleukin-2 based immunotherapy

The role of interleukin-2 based immunotherapy in advanced renal cell carcinoma is gradually expanding. Among patients who achieve significant responses to these regimens the subsequent development of isolated recurrences raises difficult management questions. We report 2 unusual cases of isolated recurrence in the remaining kidney following a sustained, complete response to interleukin-2 based adoptive immunotherapy. Both patients were treated with interleukin-2 based therapy following surgical resection of the primary renal tumor. The disease course of each patient is described and the literature is reviewed. Both patients were free of disease after relatively short-term followup. Surgery for patients with limited recurrence of renal cell carcinoma following an objective response to immunotherapy may, in select cases, be a reasonable treatment alternative.

Clonal analysis of peripheral blood lymphocytes from three patients with advanced neuroblastoma receiving recombinant interleukin-2 and interferon alpha

In this study we have investigated, at the population and the clonal levels, the immunophenotypes and the non-specific cytotoxic functions of peripheral blood lymphocytes from three stage IV neuroblastoma patients receiving treatment with recombinant interleukin-2 (IL-2) and interferon alpha (IFN alpha). Both IL-2 alone and the combination of IL-2 and IFN alpha caused an in vivo expansion of CD56+, CD3- NK cells most of which expressed the p75 molecule, i.e. the beta chain of the IL-2 receptor. Peripheral blood mononuclear cells (PBMC), drawn after treatment, displayed an increased NK activity, but no lymphokine-activated killer (LAK) activity. However, the subsequent in vitro culture of PBMC with high-dose IL-2 induced the generation of a potent LAK activity, which was mediated by an expanded population of CD3+, CD8+ T cells. Finally lymphocytes that had been isolated after cytokine therapy were cloned, in the presence of low-dose phytohemagglutin, immediately or following culture with IL-2. Clones derived from LAK cells expanded in vitro had predominantly a CD3+, CD8+ immunophenotype, whereas those raised from freshly separated lymphocytes were either CD3+, CD4+ or CD3+, CD8+ in equal proportions. Most of the above clones were poorly or not at all cytolytic against NK-sensitive or NK-resistant targets. In contrast, the few NK clones obtained (CD3-, CD56+) lysed all targets with high efficiency.

Intensity of class I antigen expression on human tumour cell lines and its relevance to the efficiency of non-MHC-restricted killing

A modified tetrazolium reduction assay (MTT) was used to assess the relation between HLA class I antigen expression on tumour cells and their susceptibility as a target for non-MHC restricted LAK/NK cytotoxicity using interleukin-2 activated peripheral blood mononuclear cells (MNC) from normal individuals. At 20/1 effector/target ratio this ranged from no killing to 77%. The efficiency of killing was dependent on duration of effector cell culture with IL-2, peaking at day 10 and declining thereafter. This killing could be enhanced by addition of other cytokines including interferons alpha, beta and gamma. Study of a panel of 15 tumour cell lines using a single effector showed that there was no statistically significant inverse correlation (using Spearman rank test) between the degree of tumour class I expression and LAK/NK killing at 20/1 (r = 0.23 P = 0.39) and 10/1 (r = 0.30, P = 0.27) and at 5/1 E/T ratio r = 0.47, P = 0.08) respectively. Lack of inverse correlation between these two parameters came from study of one bladder tumour line (FEN), whose absent class I antigens had been corrected by transfection with beta 2 microglobulin gene. At high E/T ratio (20/1) there was an increase in the susceptibility of target cells to lysis (36% parent cell, 45% transfected cell), whilst at lower E/T ratios (1/1) there was significantly more killing of the non-transfected cells (10% vs 31%). The addition of anti-class I antibody W6/32 increased killing by 18% but this was non-specific as the same increase occurred with a class II antibody. These data suggest that overall there was not an inverse correlation between class I expression and LAK/NK killing at high E/T ratios, whilst at low (5/1 or lower) E/T ratios this correlation nearly reached statistical significance suggesting that the conflicting literature reports may be due to a threshold levels of effector cells above which the masking effects of MHC antigens disappears.

Survival characteristics of metastatic renal cell carcinoma patients treated with lymphokine-activated killer cells plus interleukin-2

The immunologic manipulation of patients with metastatic renal cell carcinoma using lymphokine-activated killer (LAK) cells in conjunction with systemic interleukin-2 (IL-2) has been examined under conditions in which the life-threatening toxicities associated with IL-2 treatment have been virtually eliminated. We have examined tumor regression in vivo as well as the survival characteristics of 12 patients with metastatic renal cell carcinoma following immunotherapy. Five of 12 (42%) patients experienced tumor regression exceeding 50 percent following treatment. To determine if immunotherapy had influenced the length of survival, all patients were followed until the time of death. Previous studies have characterized the length of survival of metastatic renal cell cancer patients according to a combination of risk factors unique for each patient. In this model, patients were categorized into risk groups based on the number of risk factors. Survival was found to be dependent on risk factors such as performance status, time from initial diagnosis, number of metastatic sites, recent weight loss, and prior cytotoxic chemotherapy. On completion of the LAK cell immunotherapy protocol, patients were categorized as nonresponders or responders. In addition, they were assigned to risk groups based on their unique profile of risk factors at the time of entry into the protocol. Using this model, we found the median survival of nonresponders (23 months) to be no different from responders (24 months), p > 0.05. This was directly attributable to differences in risk factors which characterized members in these two response groups. However, the observed median survival of nonresponders following therapy was 1.9-fold longer than their projected survival based on the risk factors. Furthermore, the observed median survival of responders was 3.4-fold longer than projected from their risk factors. These results suggest that regardless of response status to therapy, cellular immunotherapy may play a role in mediating a significant palliative effect on the metabolic characteristics of these patients leading to extended survival.

Gene transfer therapy in cancer

Gene transfer techniques have now achieved clinical realization in the wake of recent advances in recombinant DNA technology, together with increased understanding of the molecular biology and immunology of cancer. These novel treatments, and their applications and limitations merit intensive study.

A phase I study of subcutaneous recombinant interleukin-2 and interferon alfa-2a

BACKGROUND

Both recombinant interferon alfa and interleukin-2 (IL-2) have been shown to have some activity as single agents in metastatic renal cell cancer (RCC), although their activity is minimal in more common solid tumors. Recent preclinical studies have suggested that the combination of these two agents is especially promising.

METHODS

Subcutaneous recombinant interferon alfa-2a and IL-2 were administered at one of five dose levels to 33 patients with refractory solid tumors, including 21 patients with RCC. A constant ratio of 5:1 of interferon alfa-2a to IL-2 was used. Interferon alfa-2a and IL-2 were administered three and five times weekly, respectively, for a total of 4 weeks, followed by a rest of 1-3 weeks between cycles.

RESULTS

The dose-limiting toxic effects included hypotension, nephrotoxicity, and fatigue. At the recommended Phase II dose of 7.5 million units (MU)/m2 of interferon alfa-2a and 1.5 MU/m2 of IL-2, 12 patients were treated. Ten of 12 completed the 4-week cycle without modification. Four patients at that dose level had Grade 3-4 toxic effects. Partial responses were observed in 4 of 16 assessable patients with RCC.

CONCLUSIONS

Subcutaneous interferon alfa-2a and IL-2 can be self-administered safely on an outpatient basis. At tolerable doses, responses can be achieved in metastatic RCC.

Intensive recombinant interleukin-2 and alpha-interferon therapy in patients with advanced head and neck squamous carcinoma

BACKGROUND

Cellular immune deficiency is a consistent finding in patients with advanced head and neck cancer. Interleukin-2 and alpha-interferon are modulators of the immune system.

METHODS

Eleven patients with recurrent head and neck cancer were treated in a Phase II study of recombinant human interleukin-2 (rIL-2) and alpha-2a-interferon (Roferon-A, Hoffmann-La Roche, Inc., Nutley, NJ). Each course consisted of rIL-2, 3 x 10(6) U/m2/day, as a continuous intravenous infusion over 24 hours for 4 days, and recombinant alpha-2a-interferon, 5 x 10(6) U/m2/day intramuscularly or subcutaneously daily for 4 days. This treatment was repeated weekly for 4 weeks, and then a second cycle was given after a 2-week break.

RESULTS

Two patients (18%) achieved a partial response. Toxic effects were substantial. Three of 11 patients experienced Grade 3 hypotension, 3 patients had Grade 3 oliguria, and Grade 3 fatigue was one of the most common reasons for withdrawal from the study. There were no deaths or need for intensive care monitoring.

CONCLUSIONS

In view of the 18% response rate, additional investigation of biologic therapy in advanced head and neck cancer is warranted.

A new approach for measurement of cytotoxicity using colorimetric assay

Using in vitro established tumour cell lines attempts were made to assess the suitability of tetrazolium salt reduction (MTT) assay to replace the conventional radioactive base techniques for measuring cell proliferation and cell killing. The optimum conditions for MTT loading time, concentration of MTT and the time for colour development were found to be 4 h, 5 mg/ml and 30 min respectively, conditions which were used for subsequent experiments. Analysis of the correlation between increasing cell numbers and optical densities (OD) showed a direct relationship with correlation of coefficient values of r > 0.98 and 10,000 cells/well was found to provide an accurate ODs for a wide variety of cell types. The accuracy of replicate readings of the assay was investigated by setting a wide range of cell numbers and the variation among seven replicates was calculated and found to be less that 6% of the mean values. The reproducibility of the assay for two cell lines was tested using the lines on four different occasions. The ODs for Jar and Fen cell lines were 0.80 +/- 0.01, 0.82 +/- 0.02, 0.90 +/- 0.02, 0.79 +/- 0.05 and 0.56 +/- 0.01, 0.58 +/- 0.03, 0.60 +/- 0.02 and 0.61 +/- 0.02 respectively giving maximum variation of less than 11% of mean on repeated testings. Comparison between the results of MTT with 3H-Tdr or 51Cr release assays showed a high degree of correlation over a wide range of cell numbers and cell types. The r values between the results of MTT with 3H-Tdr (for cell number ranging from 1.8 to 60 x 10(3)/well) or 51Cr release assays (for E/T ratios of between 5:1 and 40:1) were 0.89 (p = 0.001) and 0.96 (p < 0.03) respectively. These results demonstrate that it is possible to use the MTT assay interchangeably with radioactive base techniques to measure cell proliferation and cytotoxicity. The ease of its execution, safety and its suitability for analysing as few as 3000 cells makes this method a serious contender for replacing the conventional radioactive techniques.

Interleukin-2 and interferon in renal cell carcinoma

Renal cell cancer (RCC) represents an unusual solid tumor for which no treatment other than surgical therapy has been effective. This tumor demonstrates a remarkably heterogeneous behaviour and rare reports of spontaneous regressions suggest an unusual sensitivity to host immunologic control. In recent years the rapid development in molecular genetics, growth factors and cytokine--lymphocyte interactions have increased the interest and possibilities for immunotherapy of RCC. Interleukin-2 (IL-2) or Interferon alpha (IFN alpha) alone are only marginally active in RCC. Their different modes of action and their synergistic effects when used in experimental murine models prompted the investigation of combined IL-2/INF alpha therapy in advanced RCC. The advantage of a combination of IL-2 and IFN alpha treatment as compared to LAK cell treatment seems to be that IL-2 and IFN alpha can be given at lower dosages without compromising the results in an outpatient setting. This article reviews the use of IL-2 and IFN alpha in combination for treatment of RCC and discusses the current problems and future challenges in this field.

Changing role of splenectomy for hematologic disease

In the past decade the development of accurate imaging and the evolution of the medical management of hematologic diseases has led to changes in the indications for splenectomy for these disorders. To assess the impact of these developments, a multi-institutional, retrospective review was undertaken. One hundred fifty-six splenectomies were performed for hematologic disorders between July 1, 1979 and June 30, 1991. Patients were divided into 2 groups: those undergoing splenectomy from 1979-1985 (Period I), and those undergoing splenectomy from 1986-1991 (Period II). Diseases were classified into 3 groups: cytopenic/anemic conditions, symptomatic splenomegaly, and Hodgkin's disease. Data was compared between the two periods using chi-square analysis. More splenectomies were performed for hematologic disorders during Period II than Period I (P < .005). This increase is secondary to a rise in the number of splenectomies performed for cytopenia/anemia during Period II. In contrast, splenectomies for splenomegaly and Hodgkin's disease decreased during Period II (P < .005 and < .05). More Hodgkin's patients were upstaged on the basis of positive laparotomy findings in Period II, compared to Period I (40% versus 10%, P = .01). Surgeons are now performing more splenectomies for cytopenic/anemic diseases, and fewer for splenomegaly and Hodgkin's disease. These results are consistent with recent trends: (1) earlier splenectomy in patients with cytopenia/anemia; (2) earlier medical intervention in infiltrative splenic disorders; and (3) more reliance on radiologic staging in Hodgkin's disease and widespread use of combination chemotherapy, leaving surgical staging for those cases in which treatment would be changed by laparotomy findings.

Interleukin 2 therapy: current role in surgical oncological practice

The use of recombinant interleukin 2 (rIL-2) in clinical practice has opened up new and beneficial avenues in the treatment of certain malignant diseases. Although rIL-2 can stimulate a range of host antitumour defence mechanisms, only 30-40 per cent of patients who are treated will respond to such therapy as assessed by a reduction in tumour volume. The effect of rIL-2-based treatment schedules on delaying progression of disease and on overall survival in comparison with standard current treatments and chemotherapeutic regimens is not clear. Randomized clinical trials are required to evaluate precisely the role of rIL-2 in various therapeutic combinations and to ascertain the optimum therapeutic regimens for individual tumour types. Studies currently under way should provide more insight into the possible beneficial effects of immunotherapy with rIL-2. More basic research is required to ascertain how rIL-2 may produce its antitumour effects and why the therapeutic results obtained in humans have been so selective and less beneficial than those in experimental animals.

Advances in systemic treatment of malignant melanoma

This paper reviews recent developments in the systemic treatment of advanced malignant melanoma. In the introduction emphasis is given to prevention and early detection of this disease. Metastatic malignant melanoma patients have a median survival of less than 1 year in the most favourable situation. Adjuvant chemotherapeutic treatment after initial surgery has not had an impact on prognosis, while immunological manipulations with interferon alfa or other agents may prove beneficial after primary surgery. In advanced disease which cannot be palliated by surgery, many approaches are under investigation. Modulation of the patient's immune response can be achieved with vaccines, monoclonal antibodies, interleukin-2 and interferons, as single agents or in combination between themselves or with peripheral blood mononuclear cells or with tumour infiltrating lymphocytes or even with chemotherapy. Immunological approaches yield a 20-30% response rate, with some possibly long-term responses. Chemotherapeutic agents have a 10-30% response rate, which is usually of short duration. Combinations of chemotherapeutic agents can increase the response rate to 50%, but an impact on ultimate survival seems unlikely. Randomised studies have shown that modulation of chemotherapy with interferon or tamoxifen improves response rates. Clinicians should be encouraged to enter their patients with malignant melanoma in therapeutic trials.

Combination of interleukin-2 and gamma interferon in metastatic renal cell carcinoma

The use of high-dose interleukin-2 (IL2), alone or in association with lymphokine activated killer cells in patients with metastatic renal cell carcinoma (MRCC) results in a 20-25% response rate. However, the toxicity of IL2 is substantial and despite many clinical trials, response rates initially reported have not been improved. The aim of this study was to evaluate a combination of IL2 and gamma interferon (IFN) in MRCC with respect to both efficacy and tolerance. IL2 was given by continuous intravenous infusion at a daily dose of 24 x 10(6) U/m2 for 2 consecutive days during 5 consecutive weeks. Gamma IFN was given subcutaneously at a daily dose of 5 x 10(6) U/m2 on the same days as IL2. 33 patients with MRCC entered the study. Clinical responses were comparable with other published series: 7 patients (21%) achieved partial response, 13 (39%) were stable and 13 had progression, despite therapy. Immunological profile observed with this regimen showed a major increase in natural killer cells which became the predominant lymphocyte population at the end of the therapy. Tolerance was good with 92.5% of the planned doses actually received by the patients. This was reflected by an early discharge from the hospital in 95% of the cycles, increasing acceptability of the regimen by the patients.

Medical Treatment of Advanced Renal Cell Carcinoma

Therapy for disseminated renal cell carcinoma is a major problem, as it's almost completely resistant to standard therapeutic approaches such as chemotherapy or radiotherapy. The search for innovative strategies has led to new concepts based on the assumption that cellular or soluble mediators of the immune system can be rendered cytotoxic or cytostatic for renal cell cancer. With partial response rates of ca. 100% and very promising global response rates, biotherapies are in progress. A number of clinical trials have been perfomed employing systemic administration of interferon (rIFN-) alone or in combination with cytostatic agents, human recombinant interleukin-2 (rlL-2), and, more recently, immunomodulatory agents such as lymphokine-activated killer (LAK) cells: these substances have been demonstrated to be a treatment of choice for advanced renal cell carcinoma, even if they seem unable to modify the natural history of the disease.

Continuous Circadian Infusion of Fudr Associated with Interferon in Metastatic Renal Cell Cancer Treatment

The prognosis of metastatic renal cell cancer (RCC) is poor due to the lack of an effective treatment. Continuous circadian infusion of FUDR (5-fluoro-deoxyuridine) by the implantable Synchromed-Medtronic infusion system achieves an effective response in 24% of cases. The association with interferon seems to increase response rate. The Authors report their preliminary experience in 5 patients with metastatic RCC treated with chronoinfusion of FUDR and interferon. All patients tolerated the treatment well and no major toxicity was observed.