Immunological and clinical effects of intramuscular rIFN alpha-2a and low dose subcutaneous rIL-2 in patients with advanced malignant melanoma

Update on therapy for melanoma: opportunities for patient selection and overcoming tumor resistance

The incidence of malignant melanoma is rising faster than any other malignancy. Although earlier stage patients can be cured with surgical resection with or without adjuvant therapy, a significant number of patients go on to develop disseminated disease. Currently, limited therapeutic options exist for patients with metastatic melanoma. Recent studies suggest that patient selection is feasible and may enable the restriction of treatment to those most likely to benefit. Additionally, several potential mechanisms of tumor resistance have been identified creating opportunities for circumventing them. This article will review current strategies for patient selection and overcoming therapeutic resistance. These strategies hold the promise of extending the clinical benefits of current therapies as well as facilitating the development of additional and more active treatments.

Plasma Homocysteine and Immune Activation in Patients with Malignant Melanoma Undergoing Treatment with IFN-α

Immune activation and cell proliferation may contribute to the development of increased homocysteine concentrations in patients with malignant diseases. In this study, we investigated the effect of interferon-alpha (IFN-alpha) on plasma homocysteine concentrations in patients being treated for malignant melanoma. In parallel, neopterin formation and tryptophan degradation were monitored to assess the capacity of IFN-alpha to activate macrophages. Plasma concentrations of homocysteine, folate, and vitamin B(12) were determined in 15 patients with malignant melanoma during 12 weeks of high-dose IFN-alpha therapy. Concurrently, concentrations of neopterin, tryptophan, and kynurenine were measured, and the kynurenine/tryptophan ratio (kyn/trp) was calculated. Homocysteine and folate concentrations during treatment with IFN-alpha did not differ from baseline. In contrast, significant increases in neopterin formation and tryptophan degradation were apparent during IFN-alpha therapy. Plasma concentrations of vitamin B(12) and cysteine also increased. These results indicate that IFN-alpha directly activates macrophages to release neopterin and to degrade tryptophan, but obviously treatment with INF-alpha did not affect homocysteine metabolism.

Intermediate dose recombinant interferon-alpha as second-line treatment for patients with recurrent cutaneous melanoma who were pretreated with low dose interferon

BACKGROUND

Interferon (IFN) is widely considered the most effective agent in the adjuvant therapy of patients with cutaneous melanoma (CM). However, little is known about the effect of IFN on pretreated CM patients who experience disease recurrence. The authors conducted a Phase II study to determine whether intermediate doses of IFN could be beneficial for these patients.

METHODS

A series of 24 consecutive CM patients who had undergone surgery for local, in-transit, or lymph node disease recurrence during adjuvant therapy with low dose IFN (IFNalpha-2b, 3 million units [MU] per day, three times per week) were enrolled for second-line therapy with intermediate dose IFN (IFNalpha-2b, 10 MU per day) for one year.

RESULTS

IFN was discontinued in 7 patients (29.2%) because of toxicity. Several patients complained of impairment in their daily activities. Progression of disease was registered in 17 patients (70. 8%), with a median disease free survival of 5.5 months (95% confidence interval, 3.4-14.2). The median follow-up for the 7 patients who did not experience disease recurrence was 15 months (range, 13-22 months).

CONCLUSIONS

An increased dose of IFN as second-line adjuvant treatment was poorly tolerated and produced negative clinical outcomes in patients with CM. However, these patients probably were unresponsive to IFN regardless of the dosage level. In fact, the first adjuvant IFN treatment was ineffective in all patients. Thus, the key factor in the treatment of CM seems to be patient responsiveness to IFN rather than the total dosage achieved.

GM-CSF with biochemotherapy (cisplatin, DTIC, tamoxifen, IL-2 and interferon-alpha): a phase I trial in melanoma

BACKGROUND

Ineffective tumour antigen processing is recognised as an important cause of failure of immunotherapy in melanoma. GM-CSF may augment the cytotoxic lymphocyte response by activating antigen-presenting cells. This study evaluates a schedule combining GM-CSF with biochemotherapy.

PATIENTS AND METHODS

Nineteen patients with advanced malignant melanoma received cisplatin (25 mg/m2 days 1-3). dacarbazine (220 mg/m2 days 1-3), interleukin-2 (9 MIU/m2/24 h) and interferon-alpha2b (5 MIU/m2) both days 6-10 and days 17-21, and tamoxifen 40 mg/day continuously. Subcutaneous GM-CSF was given in escalating doses to three cohorts: 1) 450 microg/m2 days 4-5 and 15-16; 2) as 1) plus 225 microg/m2 days 6-10 and 17-21; 3) 450 microg/m2 days 4-10 and 15-21. Each cycle was 28 days.

RESULTS

Constitutional side effects were the major non-haematological toxicity and lymphopaenia the main haematological toxicity. Six patients responded (32%, 95% confidence interval: 13%-57%), two patients had complete remission. There was an apparent trend for increasing responses with increasing GM-CSF dose; zero of six responses in cohort 1, two of seven in cohort 2 and three of six in cohort 3 (P = 0.016). Median overall survival was 6.2 months. Increasing GM-CSF doses significantly increased serum concentrations of neopterin and TNF-alpha.

CONCLUSIONS

The combination of GM-CSF with biochemotherapy is feasible and there appears to be a dose-response relationship with GM-CSF in terms of host immunological response, and possibly clinical efficacy.

Randomized phase II trial of BCDT [carmustine (BCNU), cisplatin, dacarbazine (DTIC) and tamoxifen] with or without interferon alpha (IFN-alpha) and interleukin (IL-2) in patients with metastatic melanoma

The purpose of this study was to evaluate in a randomized phase II trial the efficacy and toxicity of combination biochemotherapy compared with chemotherapy alone in patients with metastatic melanoma. Sixty-five patients with metastatic melanoma (ECOG performance status 0 or 1) were randomized to receive intravenous BCNU 100 mg m(-2) (day 1, alternate courses), cisplatin 25 mg m(-2) (days 1-3), DTIC 220 mg m(-2) (days 1-3) and oral tamoxifen 40 mg (BCDT regimen) with (n = 35) or without (n = 30) subcutaneous interleukin 2 (IL-2) 18 x 10(6) iu t.d.s. (day - 2), 9 x 10(6) iu b.d. (day - 1 and 0) and interferon 2 alpha (IFN-alpha) 9 MU (days 1-3). Evidence for immune activation was determined by flow cytometric analysis of peripheral blood lymphocytes. Treatment was repeated every 4 weeks up to six courses depending on response. The overall response rate of BCDT with IL-2/IFN-alpha was 23% [95% confidence interval (CI) 10-40%] with one complete response (CR) and seven partial responses (PR), and for BCDT alone 27% (95% CI 12-46%) with eight PRs; the median durations of response were 2.8 months and 2.5 months respectively. Sites of response were similar in both groups. There was no difference between the two groups in progression-free survival or overall survival (median survival 5 months for BCDT with IL-2/IFNalpha and 5.5 months for BCDT alone). Although 3 days of subcutaneous IL-2 resulted in significant lymphopenia, evidence of immune activation was indicated by a significant rise in the percentage of CD56- (NK cells) and CD3/HLA-DR-positive (activated T cells) subsets, without any change in the percentage of CD4 or CD4 T-cell subsets. Toxicity assessment revealed a significantly higher incidence of severe thrombocytopenia in patients treated with combination chemotherapy than with chemotherapy alone (37% vs 13%, P = 0.03) and a higher incidence of grade 3/4 flu-like symptoms (20% vs 10%) and fatigue (26% vs 13%). The addition of subcutaneous IL-2 and IFNalpha to BCDT chemotherapy in a randomized phase II trial resulted in immune activation but did not improve response rates in patients with metastatic melanoma, and indeed may increase some treatment-related toxicity.

Cytokine therapy of malignant melanoma

Melanoma is a malignant neoplasia of melanocyte origin appearing mainly in the skin. About one third of all melanomas detected disseminate, with the metastatic spread occurring either via lymphatic or blood vessels. In the treatment of advanced melanoma the conventional chemotherapy or radiotherapy has not been very successful. Melanoma is known to have immunologically provocative features. In recent years immunological therapies, mainly cytokines, have been applied in the treatment of melanoma. The most widely used cytokines are Interferons and interleukin-2. These agents are used either alone or in combination with each other or with chemotherapeutics. Interferon and interleukin-2 therapies have yielded response rates of 15-20% on average, whereas combinations of immunotherapy and chemotherapy offer response rates as high as 50-60%. Unfortunately, average survival of patients with disseminated melanoma has been short, from 6 to 12 months. The immunotherapy approach has yielded some long-term responses and probably even a cure for a small proportion of patients. Understanding of basic mechanisms of tumour destruction by cytokines and new agents coming into clinical use will undoubtedly further improve treatment results.

Perspectives of cytokine treatment in malignant skin tumors

Cytokines have been tested in the treatment of different skin cancers during the last decade, and treatment schedules have been established or proposed for several malignant skin tumors. Preferentially, the interferons and interleukin-2 were found to be effective in treating skin cancers. Interferons alpha and beta have been approved for the treatment of human immunodeficiency virus (HIV)-associated Kaposi's sarcoma, cutaneous T cell lymphoma, and malignant melanoma in several countries. Interferon alpha was found to be most effective in cutaneous T cell lymphoma with 40%-60% overall responses. When combining interferon alpha with psoralens and ultraviolet A (PUVA) or with retinoids, even higher response rates up to 60%-90% were reported, and long-term remissions have been described. A considerable activity of interferon alpha was found in HIV-associated Kaposi's sarcoma with response rates of 30%-50%. The effectiveness of Kaposi's sarcoma's treatment was further improved by combining interferon alpha and zidovudine. Responses to interferon alpha in metastatic malignant melanoma are rather seldom (10%-15%), but a stabilization of the disease with prolonged survival was reported after interferon alpha treatment. Additionally, interleukin-2 was found to be active in metastatic melanoma, with overall response rates of about 20%, and both biological agents were found to have an additive efficacy in combination. Several combined regimens of interferon alpha, interleukin-2, and polychemotherapy have been described in metastatic melanoma, and overall response rates higher than 50% were found with these combined treatment modalities. Interferon alpha and beta were also intralesionally injected into basal cell carcinomas and other epithelial skin cancers, and complete responses were found in more than 80% of tumors treated. Local applications of interferons and interleukin-2 were likewise found to be effective in the treatment of cutaneous melanoma metastases and cutaneous manifestations of Kaposi's sarcoma. Cytokines and their combination with other treatment modalities has greatly enriched the treatment facilities in malignant skin tumors during recent years, and additional new cytokines will be introduced in skin cancer treatment in near future.

Suppressed thyroid-stimulating hormone secretion in patients treated with interleukin-2 and interferon-alpha 2b for metastatic melanoma

Recent reports suggest that combined therapy with recombinant interleukin (IL)-2 and interferon (IFN) alpha 2b may result in autoimmune-induced thyroid dysfunction. We prospectively analyzed thyroid function for 6 weeks in two groups of patients with progressive metastatic melanoma treated according to two different protocols. In group I (n = 17) three treatment cycles were given, each with three weeks of subcutanous administration of rIL-2 and INF-alpha 2b at different doses. In group II (n = 13) the chemotherapeutic agent dacarbazine was given in addition. In group 1 three patients developed frank hyperthyroidism, which required antithyroid drug therapy in one case. Autoantibodies against thyroid microsomal antigen, thyroglobulin, and the thyroid-stimulating hormone (TSH) receptor were not significantly elevated in any of these patients. However, the remaining 14 patients showed a significant decrease in TSH after 6 weeks of treatment, from 1.8 +/- 0.9 to 0.7 +/- 0.7 microU/ml (P < 0.02). Thyroid hormones (triiodothyronine, thyroxine, free thyroxine) also increased during the observation time, but this did not parallel the drop in TSH levels. Only thyroxine increased above the upper limit of normal, while triiodothyronine and free thyroxine stayed within the normal range. In group II, 6 of 13 patients (46%) had a decreased TSH after 6 weeks of treatment. Mean TSH was 1.5 +/- 1.4 before and 0.8 +/- 0.6 microU/ml after 6 weeks and was totally suppressed in three cases. None of these patients showed ouvert hyperthyroidism. Hypothyroidism was not observed in either group.(ABSTRACT TRUNCATED AT 250 WORDS)