Kaposi's sarcoma and the acquired immune deficiency syndrome. Treatment with recombinant interferon alpha and analysis of prognostic factors

Chemo-Immunotherapy of Advanced Aids-Related Kaposi'S Sarcoma

Aims and background

Kaposi's sarcoma (KS) is the most common neoplastic complication of HIV infection and AIDS. Multiple cytotoxic chemotherapy regimens have been used with various response rates. We have evaluated the efficacy and toxicity of low-dose chemotherapy in patients with poor-prognosis AIDS-related KS and the role of interferon alpha (IFN-α) in complete responders.

Methods

Twenty-five previously untreated patients with advanced KS received bleomycin (BL) 10 mg/m2 and vinblastine (VB) 6 mg/m2 on days 1 and 15 every two weeks. After six cycles, patients in complete remission received IFN-alpha (3 million U s.c. 3 times/week) combined with antiretroviral therapy. All patients were evaluated for toxicity using the World Health Organization (WHO) toxicity schedule. Both Eastern Cooperative Oncology Group (ECOG) and AIDS Clinical Trials Group (ACTG) response criteria were used to evaluate response and survival.

Results

The overall response rate was 84% (95% confidence interval, 51–117%) with six complete remissions (24%) and 15 partial remissions (60%) by ECOG criteria, and 92% (95% confidence interval: 58–128%) with 17 partial remissions (68%) by ACTG criteria. The median duration of response on IFN-alpha treatment was 4.5 months (range, 2–10). The overall median survival duration for all 25 patients was 9 months (range, 2–39). Grade 3–4 anemia was observed in five patients and grade 3–4 neutropenia in two patients. No other clinically significant (> grade 3) toxicities were observed.

Conclusions

Combination of BL and VB is effective and well tolerated, even if new therapeutic options are developing. This disease remains a challenging problem, so larger studies using the combination of chemotherapy and/or IFN-alpha with antiretroviral treatment are warranted.

Complete Regression of Laryngeal Involvement by Classic Kaposi's Sarcoma with Low-Dose Alpha-2b Interferon

We report the case of an 82-year old Italian female with laryngeal involvement of classic Kaposi's sarcoma. We obtained a complete regression of laryngeal lesion with low-dose alpha-2b interferon.

Soluble mediators of inflammation in HIV and their implications for therapeutics and vaccine development

From early in the HIV epidemic it was appreciated that many inflammatory markers such as neopterin and TNF-α were elevated in patients with AIDS. With the advent of modern technology able to measure a broad array of cytokines, we now know that from the earliest points of infection HIV induces a cytokine storm. This review will focus on how cytokines are disturbed in HIV infection and will explore potential therapeutic uses of cytokines. These factors can be used directly as therapy during HIV infection, either to suppress viral replication or prevent deleterious immune effects of infection, such as CD4+ T cell depletion. Cytokines also show great promise as adjuvants in the development of HIV vaccines, which would be critical for the eventual control of the epidemic.

Safety, tolerability, and mechanisms of antiretroviral activity of pegylated interferon Alfa-2a in HIV-1-monoinfected participants: a phase II clinical trial

BACKGROUND

To our knowledge, the antiviral activity of pegylated interferon alfa-2a has not been studied in participants with untreated human immunodeficiency virus type 1 (HIV-1) infection but without chronic hepatitis C virus (HCV) infection.

METHODS

Untreated HIV-1-infected volunteers without HCV infection received 180 microg of pegylated interferon alfa-2a weekly for 12 weeks. Changes in plasma HIV-1 RNA load, CD4(+) T cell counts, pharmacokinetics, pharmacodynamic measurements of 2',5'-oligoadenylate synthetase (OAS) activity, and induction levels of interferon-inducible genes (IFIGs) were measured. Nonparametric statistical analysis was performed.

RESULTS

Eleven participants completed 12 weeks of therapy. The median plasma viral load decrease and change in CD4(+) T cell counts at week 12 were 0.61 log(10) copies/mL (90% confidence interval [CI], 0.20-1.18 log(10) copies/mL) and -44 cells/microL (90% CI, -95 to 85 cells/microL), respectively. There was no correlation between plasma viral load decreases and concurrent pegylated interferon plasma concentrations. However, participants with larger increases in OAS level exhibited greater decreases in plasma viral load at weeks 1 and 2 (r = -0.75 [90% CI, -0.93 to -0.28] and r = -0.61 [90% CI, -0.87 to -0.09], respectively; estimated Spearman rank correlation). Participants with higher baseline IFIG levels had smaller week 12 decreases in plasma viral load (0.66 log(10) copies/mL [90% CI, 0.06-0.91 log(10) copies/mL]), whereas those with larger IFIG induction levels exhibited larger decreases in plasma viral load (-0.74 log(10) copies/mL [90% CI, -0.93 to -0.21 log(10) copies/mL]).

CONCLUSION

Pegylated interferon alfa-2a was well tolerated and exhibited statistically significant anti-HIV-1 activity in HIV-1-monoinfected patients. The anti-HIV-1 effect correlated with OAS protein levels (weeks 1 and 2) and IFIG induction levels (week 12) but not with pegylated interferon concentrations.

Anterior Segment and External Ocular Disorders Associated with Human Immunodeficiency Virus Disease

The eye is a common site for complications of human immunodeficiency virus (HIV) infection. Although cytomegalovirus retinitis remains the most prevalent of the blinding ocular disorders that can occur in individuals with the acquired immunodeficiency syndrome (AIDS), several important HIV-associated disorders may involve the anterior segment, ocular surface, and adnexae. Some of these entities, such as Kaposi sarcoma, were well described, but uncommon, before the HIV epidemic. Others, like microsporidial keratoconjunctivitis, have presentations that differ between affected individuals with HIV disease and those from the general population who are immunocompetent. The treatment of many of these diseases is challenging because of host immunodeficiency. Survival after the diagnosis of AIDS has increased among individuals with HIV disease because of more effective antiretroviral therapies and improved prophylaxis against, and treatment of, opportunistic infections. This longer survival may lead to an increased prevalence of anterior segment and external ocular disorders. In addition, the evaluation and management of disorders such as blepharitis and dry eye, which were previously overshadowed by more severe, blinding disorders, may demand increased attention, as the general health of this population improves. Not all individuals infected with HIV receive potent antiretroviral therapy, however, because of socioeconomic or other factors, and others will be intolerant of these drugs or experience drug failure. Ophthalmologists must, therefore, still be aware of the ocular findings that develop in the setting of severe immunosuppression. This article reviews the spectrum of HIV-associated anterior segment and external ocular disorders, with recommendations for their evaluation and management.

Identification of new therapies for leiomyomas: what in vitro studies can tell us

Leiomyomas are a significant problem in women's health. An understanding of the biology of these tumors and how their growth is regulated is emerging from in vitro studies using tissue specimens and cultured cells. These studies have clarified how the ovarian steroid hormones regulate growth of uterine SMCs and how the ovarian steroid ligand-receptor system has been altered in leiomyomas. Such information will allow investigators to identify steroid hormone antagonists and steroid hormone receptor modulators that may be useful for treatment of leiomyomas. We are now also developing a much better understanding of the growth factors that are produced by SMCs of leiomyoma tumors. These growth factors not only regulate the proliferation, apoptosis, and extra-cellular matrix production of the SMCs but also regulate proliferation and migration of vascular endothelial cells. Targeting these growth factors and their receptors can reduce leiomyoma growth through two different mechanisms. One targets the SMCs and the other targets the vascular system that supports the growth of the tumor. Another important lesson that can be learned from reading the scientific literature is that there are striking similarities between the biology of uterine leiomyomas and other pathologic diseases that involve mesenchymally derived cells. These include benign keloids, other fibrotic diseases such as pulmonary fibrosis, and vascular diseases such as atherosclerosis. Compounds that are developed to treat these conditions may also be beneficial for treatment of uterine leiomyomas. The next few years will undoubtedly yield many new drug discoveries for these diseases.

Immunopathogenesis of human immunodeficiency virus: implications for immune-based therapies

Human immunodeficiency virus (HIV) infection leads to a state of CD4 lymphopenia and generalized immune activation with subsequent development of opportunistic infections and neoplasms. The use of highly active antiretroviral treatment has dramatically improved the clinical outcome for HIV-infected patients, but the associated cost and toxicity and the eventual development of drug resistance have underscored the need for additional therapeutic strategies. Immune-based therapies, such as treatment with cytokines or immunosuppressants, adoptive immunotherapy, and therapeutic immunizations, are being intensely investigated as potential supplements to antiretroviral therapy. Although much data have been generated as a result of these efforts, to date there has been little evidence of the clinical efficacy of these strategies. Randomized clinical studies remain critical in evaluating the clinical significance and the role of immune-based therapies in the therapeutic armamentarium against HIV.

Interferon-alpha is a potent inhibitor of basic fibroblast growth factor-stimulated cell proliferation in human uterine cells

PROBLEM

Abnormal uterine bleeding is a significant health problem for many women and is the number-one reason for performing hysterectomy in the United States. Leiomyomas (uterine fibroids) are benign neoplasms that are a frequent cause of abnormal uterine bleeding. The goal of this study was to assess the effects of the anti-angiogenic cytokine, interferon (INF)-alpha, on the proliferation of both leiomyoma and normal uterine cells.

METHOD OF STUDY

Primary cultures of leiomyoma, myometrial, and endometrial stromal cells were established for in vitro study. The effects of INF-alpha (10, 100, and 1000 U/ml) were tested on serum-stimulated and basic fibroblast growth factor-stimulated cell proliferation using the [3H]thymidine incorporation assay.

RESULTS

INF-alpha was a potent inhibitor of cell proliferation for all three cell types, with endometrial stromal cells showing the greatest sensitivity. The antiproliferative effect did not appear to result from toxic effects on the cells.

CONCLUSION

INFs may prove to be useful therapeutic agents for the treatment of leiomyoma-related abnormal uterine bleeding.

Interferons in dermatology. Present-day standard

Since the first clinical trials in the early 1980s with recombinant interferon, it was possible to show for a variety of indications that cytokines, especially interferons, at certain doses and at respective intervals, when applied in combination with other pharmaceutical compounds open new powerful therapeutic possibilities. Worldwide, recombinant interferon is licensed, especially in dermato-oncology, for the indication of HIV-associated Kaposi's sarcoma, cutaneous T-cell lymphoma, and recently for adjuvant therapy of high-risk malignant melanoma. Recombinant interferon is at present not licensed for dermatologic indication (septic granulomatosis). At the end of our century the indication spectrum for interferons as monotherapy and as combination therapy will undoubtedly be extended. Larger and controlled studies will prove the importance of interferons in dermato-oncology as well as in inflammatory and infectious dermatoses. The combination of interferons with standard therapies will surely be of the utmost importance in dermatotherapy.

[Kaposi sarcoma]

Moriz Kaposi was the first who, in 1872, described five patients presenting with "sarcoma idiopathicum multiple hemorrhagicum". In 1912 Sternberg termed this disease Kaposi's sarcoma. Since then various forms of this rare disease have been observed. In 1914 Hallenberg described the first cases of African or endemic Kaposi's sarcoma. In the 1960s the first reports discussing Kaposi's sarcoma following organ transplantation and immunosuppressive therapy were published. After 1981, the epidemic form associated with the acquired immunodeficiency syndrome (AIDS) was described. All these forms, their history, treatment methods and the role of radiation therapy in the management of this rare malignancy are discussed, and the literature is reviewed.

A phase II study of recombinant human interferon-alpha 2a and zidovudine in patients with AIDS-related Kaposi's sarcoma. AIDS Clinical Trials Group

To assess safety, antitumor response, and immunological and virological activity of interferon-alpha 2a and zidovudine combination therapy in patients with AIDS-related Kaposi's sarcoma, we conducted an open-label, Phase II, multicenter study. Sixty-three patients with biopsy-proven Kaposi's sarcoma and no previous interferon-alpha therapy received zidovudine 600 mg/day and interferon-alpha 2a 18 x 10(6) U/day. The median duration of follow-up was 49 weeks. Of 62 evaluable patients, 25 (40%; 95% confidence interval, 0.28-0.52) showed a complete (26%) or partial (15%) antitumor response. Eight of 30 patients (27%) with < 100 CD4 cells/mm3 and 17 of 32 patients (53%) with > or = 100 CD4 cells/mm3 had a response. The median time to response was 36 weeks. Of the 25 patients with a response, four developed tumor progression. The median duration of response was 22.4 weeks. Eight patients (13%) developed another AIDS-defining event and 13 (21%) died. The major toxicities included anemia (16%), neutropenia (27%), elevated serum transaminases (16%), weight loss (16%), malaise (14%), fatigue (14%), fever (10%), and headache (6%). Therapy with intermediate-dose interferon-alpha 2a and zidovudine resulted in tumor regression in patients with AIDS-related Kaposi's sarcoma who had a wide range of CD4 cell counts; this therapy was relatively well tolerated.

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.

Regression of Kaposi's sarcoma after intravenous immunoglobulin treatment for polymyositis

The authors report on the case of a patient with polymyositis who was given immunosuppressive therapy and then developed Kaposi's sarcoma. Subsequently, the polymyositis was treated with high dose intravenous immunoglobulin, and the Kaposi's sarcoma regressed abruptly. The association between these two diseases and the beneficial effect of intravenous immunoglobulin on Kaposi's sarcoma are discussed.

The therapeutic effect of intralesional interferon in classical Kaposi's sarcoma

Interferon alpha-2a, which has antineoplastic, antiviral, immunomodulatory, and antiangiogenic effects, was evaluated in a prospective study, treating 10 lesions of patients with classical Kaposi's sarcoma. Ten patients received injections of interferon alpha-2a intralesionally in a dose of 3 million units three times weekly for 4 weeks, and in a variable dose for 4 more weeks. Two of the patients had a complete response, and in one of these, distant lesions also responded. Seven had a partial response, and one did not respond. The treatment was generally well tolerated. The results of our study support the use of interferon in the therapy of classical Kaposi's sarcoma, although it would appear that to achieve maximum efficacy, a longer period of treatment is needed.

Potentiation of cytotoxicity of Kaposi's sarcoma related to immunodeficiency syndrome (AIDS) by liposome-encapsulated doxorubicin

Kaposi's sarcoma is an independent criterion for the diagnosis of AIDS and develops in nearly 15% of all cases. Current chemotherapy regimens are associated with substantial toxicity, particularly bone marrow suppression, which limit their long-term use. In an attempt to reduce treatment-related toxicity and enhance uptake of the drug in tumor cells, free and liposome-encapsulated doxorubicin was tested in vitro. The liposomes were prepared with cardiolipin, phosphatidylcholine, and cholesterol. Kaposi's sarcoma (KS)-derived spindle cells were exposed to free doxorubicin (DOX) and liposome-encapsulated doxorubicin (LED) for various time intervals and analyzed for cellular cytotoxicity, thymidine incorporation, and cellular drug uptake. Cytotoxicity studies of KS cells with free DOX and LED showed an IC50 of 288 and 7.5 ng/ml, respectively, hence demonstrating a 38-fold higher cytotoxicity by LED. Thymidine incorporation studies in KS cells demonstrated over one log higher toxicity to LED compared to free DOX. Cellular drug uptake studies showed that free DOX concentration peaked in 1 hr in KS cells whereas LED continued to accumulate up to 4 hr. At 4 hr, anthracycline uptake through LED was fivefold higher than the uptake of free drug. Similarly LED uptake in the cells evaluated by direct fluorescent microscopy was much more intense and more frequent than the uptake of free drug. Thus AIDS-KS cells appear to be exquisitely sensitive to LED, which may provide a higher therapeutic to toxicity index in clinical use.

Kaposi's sarcoma. Epidemiology, pathogenesis, histology, clinical spectrum, staging criteria and therapy

The acquired immunodeficiency syndrome (AIDS) epidemic has had a profound impact on our understanding of Kaposi's sarcoma (KS). Epidemiologic features suggest a sexually transmitted cofactor in the pathogenesis of AIDS-associated KS (AIDS-KS), and several putative agents have received intense scrutiny. Cell culture studies suggest that the angiogenesis of AIDS-KS is stimulated by both human immunodeficiency virus proteins and growth factors that may be involved in the development and progression of AIDS-KS, thereby providing a rationale for new therapeutic interventions. The dermatologist is uniquely qualified to provide care for the majority of patients with KS, as many patients have cutaneous lesions amendable to local therapy (cryotherapy, intralesional therapy, simple excision). Patients requiring more aggressive local therapy (radiation therapy) or systemic therapies (interferon, chemotherapy) can be easily recognized. Standardized staging criteria provide assistance for determining appropriate local or systemic therapy and for evaluating and comparing responses to new therapies. This article reviews the epidemiology, pathogenesis, histologic features, clinical spectrum, staging criteria, and treatment of KS.

Kaposi's sarcoma of the head and neck in acquired immunodeficiency syndrome

Kaposi's sarcoma has emerged from obscurity to become a common treatment problem. Otolaryngologists can play a key role in diagnosis and treatment of the victims of AIDS given the frequency of involvement of the head and neck. Kaposi's sarcoma involvement of the head and neck is often the presenting symptom of AIDS, making accuracy in diagnosis critical if intervention is to begin early. KS is rarely the cause of death in these patients, although it can cause significant morbidity. Treatment is currently directed toward palliation for pain, bleeding, dysphagia, airway obstruction, severe disfigurement, and prophylaxis for rapidly progressive tumor. The choice of treatment is dependent on the symptoms, location, and extent of the lesion. Radiation, chemotherapy, and alpha interferon form the core of treatment, with the former two more commonly used. The general medical condition of the patient must be considered, particularly when systemic treatment is contemplated. Future directions of therapy may be directed toward optimizing combination therapy and modification of the underlying immunodeficiency to allow the body's own compromised immunity to cause regression of the tumor.

AIDS-associated Kaposi's sarcoma and the mechanisms of interferon alpha's activity; a riddle within a puzzle

As yet, the pathogenesis of Kaposi's sarcoma in the context of the acquired immunodeficiency syndrome (AIDS) is not completely understood; this is also true for the mechanisms of action of interferon-alpha against this tumour. The present review focuses on recent developments that may provide some further insight into these issues. These include the angiogenesis of the tumour and the possible role of growth factors, such as the HIV-transactivating (tat) gene product and interleukin-6, the possible meaning of immunomodulating activities of interferon-alpha, such as the rise in the number of CD4+ cells and the increase in beta 2-microglobulin serum concentrations in patients whose tumours respond to treatment, and the observed association between interferon's antiretroviral activity and tumour responses.

Development of immunotherapeutic strategies for the treatment of malignant neoplasms

Focused preclinical studies have been used to gain insight into the mechanism of therapeutic activity of cytokines, growth factors and biological response modifiers (BRMs). These data can then be used to develop a clinical hypothesis to facilitate the development of these new biological drugs. In this manuscript, we discuss a number of preclinical and clinical studies using interferon-gamma, IL-2, and the colony stimulating factors. The importance of the systematic profiling of the biological activity of such biological drugs is emphasized and we discuss the utility of the mechanistic data in their clinical development. The overall preclinical approach identifies the cellular, biochemical or gene regulatory event that is associated with the therapeutic activity of a biologic and this surrogate (be it biological, chemical, or quality of life) is then used to optimize the clinical protocol in a phase 1b trial. This, in theory, results in the rapid identification of the optimal dose, schedule and route of administration for subsequent testing in a phase II/III clinical trial.

Head and neck malignancies associated with HIV infection

Immunosuppressed persons are at greater risk of developing malignancies. In human immunodeficiency virus (HIV) immunosuppression the most common oral cancers are Kaposi's sarcoma and non-Hodgkin's lymphoma. Squamous cell carcinoma has also been reported to be associated with HIV disease. Kaposi's sarcoma is the most frequent neoplastic disease in acquired immunodeficiency syndrome and is by far the most common in the head and neck area. This article reviews the prevalence, clinical features, and management of these diseases in HIV infection.

Combined treatment with zidovudine and lymphoblast interferon-alpha in patients with HIV-related Kaposi's sarcoma

A combination of oral zidovudine (250 mg twice daily) and subcutaneous interferon-alpha (10 x 10(6) units daily) was evaluated for clinical, antiretroviral, and immunological efficacy and for side effects in 17 patients with AIDS-related Kaposi's sarcoma. Fifteen patients were evaluable. During the study period of 12 weeks, tumor responses were complete in two patients and partial in two patients (27% major response rate). Minimal responses were seen in two patients (40% overall response rate). An anti-HIV effect (reduction of serum p24 antigen by 70% or more) was observed in seven of ten evaluable patients who were initially antigenemic. CD4 lymphocyte counts remained unchanged. In six patients who had either a tumor response or a marked decline of HIV antigenemia, the treatment was continued between 12 and 59 weeks beyond the study period. Two of four patients with tumor regression at 12 weeks had an additional tumor response in this period despite prior dose reduction of interferon due to toxicity. Late progression of KS was eventually observed in four of six patients on prolonged treatment. The responsiveness of Kaposi's sarcoma seen in this study in patients with low CD4 counts and prior constitutional symptoms (fever, weight loss) was unexpected and needs further confirmation by larger patient groups. Dose-limiting toxicities were bone marrow depression (severe anemia in four and neutropenia with anemia in two patients), subjective adverse experiences (fever, fatigue, myalgia; four patients) and both (two patients).(ABSTRACT TRUNCATED AT 250 WORDS)

Antiretroviral therapy in combination with interferon for AIDS-related Kaposi's sarcoma

In vitro studies have shown that 3'-azido-3'-deoxythymidine (zidovudine, AZT) and interferon synergistically inhibit the replication of the human immunodeficiency virus type 1 (HIV) in peripheral blood mononuclear cells at concentrations achievable in patients. Interferon alfa can cause lesions to regress in patients with acquired immunodeficiency syndrome (AIDS)-related Kaposi's sarcoma (KS). Although zidovudine has no significant effect on the regression of these lesions, it does have antiviral activity in these patients as manifested by a decline in serum HIV antigen. However, when used separately, the two drugs can have serious side effects in some patients. In addition, the development of zidovudine-resistant strains has been noted in patients with advanced HIV disease receiving zidovudine for nine months or longer. Three in vivo trials have been initiated to assess possible advantages of combination therapy with zidovudine and interferon alfa in patients with AIDS-related KS. The incidence of serious adverse reactions, therapeutic efficacy, and the rate of emergence of zidovudine-resistant strains of HIV were evaluated. Preliminary results indicate that combination therapy with interferon alfa and zidovudine can safely be administered to patients with AIDS-related KS in doses that elicit antitumor and antiviral responses and discourage the potential emergence of zidovudine-resistant HIV strains.

Long-term therapy of HIV-associated Kaposi's sarcoma with recombinant interferon alpha-2a

Five young male patients with HIV-associated Kaposi's sarcoma (KS) were treated with recombinant interferon alpha 2a (rIFN-alpha-2a) over a period of 2-2.5 years. An IFN dose of 18 x 10(6) IU was given subcutaneously every day during the first 3 months of treatment and then on alternate days. Additional treatment with radiotherapy and laser therapy was given and, in some cases, isolated skin nodules were excised. Within 7 months of initiation of therapy one patient had a complete remission of his tumours, however, tumour progression recurred after the patient discontinued treatment. In another patient the tumour cleared within 9 months of rIFN therapy, and after 52 months he is still free of KS. The condition of a third patient tended to become stabilized during the first 6 months of therapy, but after 60 months there has been a slow progression. The fourth and fifth patients died 25 and 28 months, respectively, after the histological diagnosis of KS and the initiation of treatment. While on therapy with rIFN-alpha-2a, no life-threatening opportunistic infections occurred. The side-effects were mostly well tolerated, and no severe changes in haematological parameters were caused by the therapy.

Combined zidovudine and interferon-alpha treatment in patients with AIDS-associated Kaposi's sarcoma

The effectiveness of addition of interferon-alpha (IFN-alpha) to zidovudine in patients with AIDS-associated Kaposi's sarcoma was assessed in a non-randomized, phase II clinical trial. Twenty-one patients were treated with oral zidovudine (600 mg daily) and IFN-alpha was increased to 18 MU daily for another 4 weeks. Only one of the 20 evaluable patients achieved a partial response at 8 weeks, that lasted for 3 months. Despite IFN-alpha dose escalation in six patients, no further responses were seen. While myelotoxicity was mild, fatigue was the dose-limiting side-effect that prevented dose escalation in seven eligible patients. The combined treatment did not result in a decrease in HIV-Ag. In summary, our results indicate that the addition of IFN-alpha to zidovudine in patients with AIDS-associated Kaposi's sarcoma is not an efficacious treatment.

Long-term follow-up of 120 patients with AIDS-related Kaposi's sarcoma treated with interferon alpha-2a

One hundred and twenty patients suffering from an AIDS-related Kaposi's sarcoma treated by 18 million units of recombinant alpha-2A-interferon daily were followed prospectively for a period of between one and six years. An overall complete response was observed in 35% of these patients; the figure was significantly higher in those who did not have a visceral localization or opportunistic infections. Total lymphocyte count, CD4 lymphocyte count, and CD4/CD8 ratio were significantly higher, and beta-2-microglobuline significantly lower, in the responders than in the non-responders. A multivariate analysis showed that localization of KS and CD4 count had independent predictive value, with an odds ratio of 35 for patients who had more than 300 CD4 cells at the onset of treatment versus those with less than 150. Patients whose initially negative p24 antigenemia remained negative during treatment had the highest frequency of complete response. Among patients with initially positive p24 antigenemia, those whose percentage decrease in antigenemia levels was greatest had a higher frequency of complete response. The cumulative probability of survival in responders was 62% at four years. These results demonstrate an anti-tumoral and anti-viral effect and prolonged survival in a group of patients whose initial immune parameters were relatively well preserved. However, these results do not permit us to conclude whether these well-responding patients were treated at the onset of illness, or whether their illness was naturally less evolutive.

Long-term combined rIFN-alpha-2a and zidovudine therapy for HIV-associated Kaposi's sarcoma: clinical consequences and side effects

Interferon alpha (IFN-alpha) has been shown to be effective in treating HIV-associated KS in at least 30% of patients, and Zidovudine has proved beneficial for AIDS patients. Moreover, both drugs have demonstrated an inhibitory effect on HIV replication. Based on the above, we combined IFN-alpha and zidovudine for treatment of HIV-associated KS in order to evaluate tolerance and clinical efficacy. Twenty-one homosexual men with histologically proved HIV-associated KS were treated in an open trial with rIFN-alpha-2a 18 X 10(6) IU every second day and zidovudine 800-1200 mg/d. Treatment was discontinued within the first month in six patients: three of them developed subjective intolerance, and three others contracted severe opportunistic infections or HIV-cachexia. Fifteen evaluable patients received combination treatment over a period of 2-20 months (average 10 months). The dosage was reduced as required based on drug-induced cytotoxicity. Complete remission was observed in four patients, partial remission in three, stable disease in two, and progression in six, resulting in an overall response rate of 46%. Negative p24 expression prior to treatment was a positive predictor. Although extracutaneous involvement had a negative influence on tumor remission, even patients with a mean initial T-helper cell count below 100 mm3 responded positively. In conclusion, combination therapy of rIFN-alpha-2a with AZT may effectively control HIV-related Kaposi's sarcoma in more than 40% of patients. In contrast to monotherapy with IFN-alpha, patients with severely reduced immune systems will also benefit from combined treatment.

Treatment of the acquired immune deficiency syndrome-related Kaposi's sarcoma with bleomycin as a single agent

A nonrandomized trial was conducted to assess the efficiency and toxicity of bleomycin as a single agent in treatment of non-life-threatening AIDS-related Kaposi's sarcoma (KS). Sixty patients were enrolled in this study. They all had a disseminated and progressive non-life-threatening AIDS-related KS associated with systemic symptoms and/or CD4 lymphocyte count less than 400/mm3. Thirty patients were treated with intramuscular bleomycin (5 mg/d for 3 days every 2 or 3 weeks) and 30 others with a slow continuous intravenous infusion of bleomycin (6 mg/m3/d for 4 days every 4 weeks). The mean duration of therapy was 5 months (range, 2 to 24 months). A partial response was observed in 29 patients (48.3%) and the disease was stabilized in 18 additional patients (30%). Bleomycin failed in 21.6% of patients. Therapy had to be discontinued in two patients because of side effects. Thus bleomycin as a single agent is a good alternative therapy for AIDS-related KS.

Palliative radiation therapy for AIDS-associated Kaposi's sarcoma by using a single fraction of 800 cGy

A single radiation fraction of 800 cGy was used in the treatment of acquired immunodeficiency syndrome (AIDS)-associated Kaposi's sarcoma (KS). A total of 74 radiation treatments was given to a total of 31 patients. Of all 74 evaluable treatments, there were 25 objective major responses (6 complete, 19 partial) according to the WHO criteria, while 67 treatments resulted in subjective palliation of the main reason to treat (cosmetic discomfort, pain, or oedema). However, it appeared that the duration of these responses was rather short; in 23 of 36 radiation treatments with a follow-up of more than 4 months, progression of the tumour was seen within that time, while the palliative effect outlasted the survival of the patients in only four cases. It is concluded that a single dose of 800 cGy is an effective treatment for patients with a predicted survival of only a few months, and it should be determined whether a higher fractionated dose improves duration of responses, especially for patients with a good performance.

Clinical use of biologic response modifiers in cancer treatment: an overview. Part I. The interferons

Interferons are proteins with antiviral, antiproliferative, and immune-regulating activity. They are classified as alfa, beta, or gamma on the basis of antigenicity and biologic properties. Alfa interferons as single-agent therapy produce clinical improvement in approximately 90 percent of patients with hairy-cell leukemia, and up to 70 percent of patients with chronic myelogenous leukemia (CML) in early-stage disease. Prolonged suppression or elimination of the leukemic cell clone by interferon may ultimately increase survival of patients with CML. Interferon is not effective single-agent therapy for multiple myeloma, but improves response rate when combined with conventional agents. AIDS-associated Kaposi's sarcoma demonstrates a 40 percent objective response rate to interferon, with less risk of immune system suppression than conventional cytotoxics. Other applications of alfa interferon include malignant melanoma and renal cell carcinoma. Beta interferon is similar to the alfa subtype and may have utility in treatment of brain tumors. Gamma interferon is an important immune regulator with qualitative and quantitative differences in its efficacy and toxicity when compared with alfa interferon.

Experimental approach to the study of immune function in children with possible human immunodeficiency virus infection

The clinical immunology laboratory is often called on to assess risk in pediatric patients with clinical evidence of immunodeficiency and possible human immunodeficiency virus (HIV) exposure while antibody tests are being considered or are underway. Since non-HIV-related conditions including neoplasia, certain viruses, and primary immunodeficiency can potentially produce lymphocyte subset imbalance and functional impairment, there is need for a laboratory approach to differential analysis of pediatric immunodeficiency. In addition, laboratory methods may also influence the results obtained. In order to investigate these issues, we screened pediatric patients with and without HIV exposure. Altered lymphocyte subset expression and function were found among non-HIV-infected pediatric patients. The use of percentage and absolute lymphocyte numbers was found to affect the results obtained in a significant manner. Some patients who were chronic blood transfusion recipients were found to have blocking factors, presumably alloantibodies, in serum, which affected detection of lymphocyte surface antigens. In this population, age at seroconversion was a factor influencing subsequent levels of CD4+ T lymphocytes. Significant differences in CD4+ T lymphocyte percentages were also observed in children congenitally exposed to HIV compared with controls, even among those children with CD4/CD8 ratios greater than 1.0, who therefore had possibly escaped infection. Immune changes in children should be interpreted with caution.

Concluding remarks. Interferon therapy of diseases of the liver and gastrointestinal tract

The contribution on interferon therapy of chronic viral hepatitis published in this supplement has attracted special attention. In that article it is reported that interferon is a promising treatment of various forms of chronic viral hepatitis. Interferon treatment is also efficacious in the treatment of some gastrointestinal tumours. including metastatic endocrine gastrointestinal and pancreatic tumours and Kaposi's sarcoma in the acquired immune deficiency syndrome. However, the treatment is accompanied by many side effects. Further, especially long-term, studies are needed to determine the place of interferon treatment in these gastrointestinal and liver diseases.

Oral Kaposi's sarcoma in acquired immunodeficiency syndrome. Review of management and report of the efficacy of intralesional vinblastine

Treatment of palatal Kaposi's sarcoma (KS) with intralesional injection of vinblastine was seen to provide effective palliation. Of the ten patients studied, four had a 25% to 50% response, two 50% to 75% response, and four had 75% to 100% response with one or two intralesional injections of vinblastine. Response to treatment was followed for a mean of 3.6 months, with recurrence of lesions in two of ten patients.

Interferons in dermatology

Interferons are a large family of proteins and glycoproteins, naturally occurring or artificially produced by recombinant biotechnology. Their antiviral, antiproliferative, antitumoral, and immunomodulatory activities are induced by alterations in cell metabolism after binding to specific membrane receptors. Interferons have been used for the treatment of viral papillomas (e.g., verruca vulgaris and condyloma acuminatum), human immunodeficiency virus (HIV)-associated Kaposi's sarcoma and cutaneous tumors (e.g., melanoma, cutaneous T cell lymphoma, and basal cell carcinoma), and inflammatory dermatoses (e.g., Behçet's syndrome and psoriatic arthropathy). Clinical trials have been performed worldwide with various regimens and have not always led to conclusive results. In our experience long-term therapy with high doses of subcutaneously injected, recombinant interferon-alpha-2a in patients with HIV-associated Kaposi's sarcoma induces a remission or stabilization of the disease. In malignant melanoma a low response rate is obtained in metastatic disease with the use of interferon as a single therapeutic agent. Combined with other antitumor agents, however, interferon seems to be a useful drug. Excellent control of Behçet's disease has been obtained, and the treatment of condylomata acuminata has been effective.

Clinical evaluation of treatment with interferon

Interferons (IFNs) are biological response modifiers with antiviral and antitumoral efficacy. They are produced by almost all cells and the IFN system as a whole is an integrated part of body regulation and defence. Exogenous IFN therapy has been used since 1970 and some viral and tumor diseases respond to such therapy. Doses and schedules giving optimal effects are being worked out. IFNs are probably most valuable for the treatment of some chronic viral diseases and their effects on some benign and malignant tumors hold considerable promise for future improved applications.

Clinical effects of interferon therapy with special emphasis on antitumor efficacy

Both natural and recombinant interferons (IFNs) exert antitumor effects in man. Much work has to be done to construct optimal use of the IFN system. Its physiological role is not fully understood. Various IFN effects are described, all of which probably play a role for clinical effectiveness. Doses and schedules are discussed and pharmacokinetics and side-effects described. IFN therapy of benign and malignant tumor disease is pursued as clinical trials. Efficacy on various diseases is reported in the present article. Combination therapy is suggested for the future.

Clinical and virological effects of high-dose recombinant interferon-alpha in disseminated AIDS-related Kaposi's sarcoma

The effectiveness and antiretroviral activities of interferon-alpha in AIDS-related Kaposi's sarcoma was assessed in a non-randomised, phase-II clinical trial. 28 patients were treated with high-dose (27-36 MU) human recombinant interferon-alpha 2a subcutaneously every day for 8 weeks. In patients with stable disease or showing a response, treatment was continued three times weekly until a complete response was achieved or there was progression. 12 of the 26 evaluable patients achieved a major response; 5 of these showed histologically confirmed complete responses. There was a significant increase in OKT4-positive cells in the responders and a significant decrease in HIV antigen (HIV-Ag) in the 7 responders with initially detectable HIV-Ag. Interferon-alpha is thus an effective treatment. The increase in OKT4-positive cells and the decrease in HIV-Ag seem to be significantly related to patients with tumour responses.

Kaposi's sarcoma in AIDS patients: long-term treatment with recombinant interferon alpha-2a and chemotherapy

We evaluated the response to therapy and outcome in patients with HIV-associated KS. Eighteen of 26 patients with newly diagnosed KS were treated continuously with IFN until progression of the disease occurred. In most patients with progressive disease, chemotherapy, usually with vinca alcaloid derivatives was instituted. Results were disappointing: 10 of 26 patients (38.5%) died after a median follow-up period of 4.5 months. Survival was shortest in patients who developed opportunistic infections, malignant lymphoma, or had a low OKT4/OKT8 ratio. Only one patient showed a complete remission and one patient had a partial remission under IFN therapy. Five additional patients had stable disease. Chemotherapy was without measureable effect on KS in patients who had progressive disease under IFN. IFN therapy was associated with various, not life-threatening adverse effects and was best tolerated by patients with a low OKT4/OKT8 ratio. Our results indicate that only a small portion of AIDS patients with KS seem to benefit from a continuous treatment with IFN.

Treatment of advanced renal cell cancer with recombinant interferon alpha as a single agent and in combination with medroxyprogesterone acetate. A randomized multicenter trial

The response rates in metastatic renal cell cancer (RCC) after chemotherapy, hormonal treatment, or immunotherapy rarely exceed 15%. Recently, interferon alpha (IFN alpha) was used for treatment of this disease in several studies which also demonstrated response rates of 15%. In order to test whether IFN therapy combined with hormones would result in higher response rates we compared single agent IFN therapy with a combined therapy of rIFN alpha 2C plus medroxyprogesterone acetate (MPA) in a randomized multicenter trial. The rIFN alpha 2C (2MU) was given s.c. 5 times per week for 8-12 weeks and subsequently once weekly until week 48. In the combined treatment, 750 mg MPA was given p.o. daily until week 48 in addition to the IFN as described. The overall response rate in 93 evaluable patients was 5.4% corresponding to 2 complete and 3 partial responses. Median survival was 7 months in both treatment groups. These data confirm the ineffectivity of low IFN doses for treatment of RCC. The low response rate is not increased by addition of MPA to IFN. The analysis of other IFN studies suggests that not only IFN doses but also IFN sources may influence response rates in metastatic RCC.

Different antitumor mechanisms of interferon-alpha in the treatment of hairy cell leukemia and renal cell cancer

There is increasing evidence for the therapeutic effectiveness of Interferon-alpha (IFN-alpha) in malignant diseases. However, the antitumor mechanisms of IFN-alpha are not known. Using two examples, hairy Cell leukemia (HCL) and renal cell cancer (RCC), it is shown that the requirements for successful IFN-alpha therapy of HCL and RCC are different. In HCL low doses of IFN-alpha are sufficient to treat the disease. The reduction of hairy cells in peripheral blood is detectable within the first week of treatment. The endogenous IFN-alpha production in these patients is impaired as demonstrated by the lack of IFN-alpha induction and by low levels of 2-5 oligoadenylate synthetase in peripheral blood mononuclear cells. A possible reason for deficient endogenous IFN-alpha production is the lack of monocytes in HCL patients. It is likely that therapy with low doses of IFN-alpha substitutes for the endogenous IFN-alpha deficiency. In RCC comparatively high doses of IFN-alpha are necessary for a clinical response. There may be differences between the effectiveness of natural and recombinant alpha interferons. High doses given within a week seem to be more important than high single doses, which therefore suggests the need of daily treatment. Responses of RCC to IFN-alpha therapy are usually seen several months after the beginning of therapy. These differences in the effectiveness of IFN-alpha therapy for HCL and RCC suggest that IFN-alpha acts differently in the treatment of each disease.

Disseminated Kaposi's sarcoma in AIDS: histogenesis-related populations and influence of long-term treatment with rIFN-alpha A

Lesions (n = 19) of cutaneous Kaposi's sarcoma in different stages of development were obtained from 13 patients with acquired immunodeficiency syndrome (AIDS), and studied by light and electron microscopy. Six additional biopsies from 4 patients treated with recombinant alpha A interferon were obtained after treatment. Varying amounts of two proliferating cell populations were found: (1) Large cells showing cytologic and histochemical characteristics of endothelial cells. They were seen in close proximity to normal vessels, forming new vascular structures and large aggregates found in papular and nodular lesions. (2) Smaller spindle-shaped cells, probably of pericytic origin. They appeared in bundles and fascicles in the papillary dermis of the cutaneous Kaposi's sarcoma lesions and, in part, gave origin to thin-walled, bizarre-shaped vessels that show incomplete lumina proliferating from the upper to the deep dermis and are surrounded by extravasate erythrocytes and siderophages. After long-term systemic treatment with recombinant alpha A interferon, the endothelial type of tumor cell aggregates mostly disappeared, whereas most of the spindle-shaped pericytic-like cells were still present. Our findings lead us to suggest that some cellular product may, as a promoter factor, induce the proliferation and growth of endothelial cells. This factor may be blocked by alpha A interferon and cause regression of endothelial cell proliferation observed in AIDS patients undergoing long-term systemic therapy.