GM-CSF as an alternative to dose modification of the combination zidovudine and interferon-alpha in the treatment of AIDS-associated Kaposi's sarcoma

Cutaneous malignancy and human immunodeficiency virus disease

Certain skin cancers occur with increased frequency or altered course in patients infected with HIV. Malignant melanoma and squamous cell carcinoma are examples of cutaneous malignancies that have a more aggressive course in patients with HIV. Others, such as basal cell carcinoma, appear more frequently in this population but do not appear to be more aggressive. The incidence of HIV-associated Kapsosi's sarcoma has markedly decreased since the advent of HIV antiretroviral therapy. Our understanding of the pathogenesis of this malignancy and its unique management issues are fully reviewed. Cutaneous T-cell lymphoma (CTCL) is rare in this population. Other types of cutaneous lymphoma and HIV-associated pseudo-CTCL are discussed. This article addresses prevention, treatment, and follow-up strategies for this at-risk population.

LEARNING OBJECTIVE

At the completion of this learning activity, participants should be familiar with the unique epidemiology, clinical course, and management of cutaneous malignancy in patients infected with HIV.

Approach to the treatment of cutaneous malignancy in HIV-infected patients

Patients infected with human immunodeficiency virus (HIV) have an increased risk of developing skin cancers. These at-risk patients may have atypical presentations and/or altered clinical courses. This article will review and discuss management issues for the following malignancies: lymphomas, malignant melanoma, basal cell carcinoma, squamous cell carcinoma, and Kaposi's sarcoma.

Interferon in oncological practice: review of interferon biology, clinical applications, and toxicities

For the past 40 years, various forms of interferon (IFN) have been evaluated as therapy in a number of malignant and non-malignant diseases. With the advent of gene cloning, large quantities of pure IFN became available for clinical study. This paper reviews the biology, pharmacology, and clinical applications of IFN formulations most commonly used in oncology. It then reviews the most common side effects seen in patients treated with IFN, and makes recommendations for the management of IFN-induced toxicity. The major oncological indications for IFN include melanoma, renal cell carcinoma, AIDS-related Kaposi's sarcoma, follicular lymphoma, hairy cell leukemia, and chronic myelogenous leukemia. Unfortunately, IFN therapy is associated with significant toxicity, which can be divided into constitutional, neuropsychiatric, hematologic, and hepatic effects. These toxicities have a major impact on the patient's quality of life, and on the physician's ability to optimally treat the patient. Careful attention to all aspects of patient care can result in improved tolerability of this difficult but promising therapy.

CONCLUSION

a better understanding of IFN biology, indications, side effect profiles, and toxicity management will aid in optimizing its use in the treatment of patients with cancer.

AIDS-related malignancies

In the US over one million persons are currently infected with the HIV, over half a million have had AIDS, and over 300,000 have died from AIDS. Worldwide, it is estimated that more than 17 million people are currently infected with HIV, and over 1,200,000 cases of AIDS have been reported to the World Health Organization. By some estimates, up to 40% of patients with AIDS will ultimately develop some form of cancer. Non-Hodgkin's lymphoma, Kaposi's sarcoma and invasive cervical cancer have a higher incidence in persons with HIV infection and all three are AIDS-defining illnesses. In addition, several reports suggest that a number of other malignancies may occur at an increased incidence in persons with HIV infection, including squamous-cell carcinoma of the head, neck and anus, plasmacytoma, melanoma, small-cell lung cancer, basal-cell cancer, and germ-cell tumours. Clinicians should become familiar with HIV-related malignancies as their incidence is expected to further increase as more effective therapies for HIV and associated opportunistic infections allow patients to live longer in an advanced state of immunodeficiency. In the current article, we will review the clinical and therapeutic aspects of the most common AIDS-related malignancies including non-Hodgkin's and Hodgkin's lymphomas, Kaposi's sarcoma and anogenital epithelial neoplasias.

Malignant tumors and AIDS

One in six patients with acquired immunodeficiency syndrome (AIDS) both in the USA and Europe develop malignancies, in particular Kaposi's sarcoma (KS) and non-Hodgkin's lymphoma (NHL). After an initial rapid increase, the proportion of AIDS patients with KS steadily declined in the USA and in Europe, while the proportion of AIDS-NHL has been stable during the last decade in the USA and Europe. Human immunodeficiency virus (HIV) infected patients are living longer due to advances in antiretroviral therapy and treatment of prophylaxis against opportunistic infections, yet because of their immunodeficiency they are at high risk for cancers, especially NHL. The natural history of cancers in patients with HIV infection differs from that of the general population. Unusual aspects of tumor localization, growth behavior and therapeutical response distinguish tumors in patients with HIV infection from those without. The pathologic and virological aspects of HIV-related tumors are peculiar and a pathological classification of HIV-associated systemic lymphomas based on the morphological features of the two main types, ie, blastic and anaplastic cell lymphomas, has been formulated. The treatment of HIV-related neoplasms is controversial as it is not clear whether conventional therapy, particularly chemotherapy, is able to modify the natural history of these malignancies in the HIV setting. Moreover the treatment of HIV-related tumors presents several problems due to the aggressive behaviors of tumors and because of immunosuppressive chemotherapy employed in patients with immunodeficiency. This paper reviews the most relevant data on the epidemiology, pathology and treatment of malignant tumors in patients with HIV infection.

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.

Southwestern Internal Medicine Conference: clinical use of hematopoietic growth factors

The hematopoietic growth factors, granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF), have been cloned, produced in bacteria and yeast, and approved for clinical use in the treatment of neutropenia. Both factors stimulate the proliferation and maturation of neutrophil progenitors and enhance the effector functions of mature cells by interaction with specific receptors on the cell surface. Serum levels of G-CSF correlate inversely with the neutrophil count, suggesting that G-CSF may be the normal homeostatic regulator of the neutrophil count, while GM-CSF is generally undetectable in the serum and appears under normal physiologic conditions to act locally at inflammatory sites. Phase I and II clinical trials with these factors demonstrated minimal toxicity for G-CSF and mild to moderate dose-dependent toxicity for GM-CSF. Recent clinical trials, including double-blind, randomized studies, support a role for these growth factors in the treatment of chronic neutropenias, such as Kostmann's syndrome, acquired immune deficiency syndrome (AIDS), aplastic anemia, and myelodysplasia, as well as in acute neutropenias, such as cyclic neutropenia, chemotherapy-induced neutropenia, and bone marrow transplantation.

Therapeutic use of granulocyte-macrophage colony-stimulating factor (GM-CSF). A review of recent experience

Recombinant cytokines are now available for clinical use. Several colony-stimulating factors (CFS) have been identified which induce activation, proliferation and maturation of myeloid lineage cells. Recent therapeutic trials with granulocyte-macrophage colony-stimulating factors (GM-CSF) in association with chemotherapy, bone marrow transplantation and leukemia treatment are reviewed. GM-CSF as primary treatment for myelodysplasia and other types of bone marrow failure is also of interest. Colony-stimulating factor therapy in AIDS may be useful in order to reduce myelodepression caused by antiviral treatment and chemotherapy for associated malignancies like Kaposi's sarcoma. However, the effect of neutrophil count increase on infection is far from clear, and the real benefit of GM-CSF in cancer therapy has yet to be demonstrated.

Immunomodulatory agents in the laboratory and clinic

This paper reviews naturally occurring and synthetic compounds that either enhance immune defences or lower both natural and acquired immunity. Immunomodulatory agents used both for laboratory study and clinically for the management of immunologically based diseases are considered.

Biology and pharmacology of hematopoietic growth factors

Several glycoproteins that control blood formation have recently been characterized. Through their overlapping, synergizing, and antagonistic effects, they regulate hematopoiesis in a highly differentiated network. Large scale production of these colony stimulating factors (CSFs) has been made available by recombinant DNA technology, and a series of clinical studies in a variety of indications has been finished. In general, the subcutaneous application seems to be superior to the intravenous injection and causes less toxicity. Erythropoietin has been shown to be a highly effective treatment for anemia in patients with chronic renal failure. Granulocyte colony stimulating factor and granulocyte-macrophage colony stimulating factor are capable of ameloriating the chemotherapy induced neutropenia, and to abbreviate the time span of myeloaplasia after bone marrow transplantation. The potentials of other colony stimulating factors like Interleukin 1 and Interleukin 3, and combination regimens of several CSFs will be discussed.