Kaposi Sarcoma: A Brief Review

Generalized papular, erythematous, nonpruritic, hyperpigmented lesions had appeared on the face, arms (A), chest, and abdomen of a 25-year-old homosexual man with AIDS during the previous month. Anupama Ravi, MD, of Atlanta also noted purple-red, nodular lesions in the right conjunctiva (B) and oral cavity, especially the lower gingiva (C). Other pertinent physical findings included facial edema and hepatosplenomegaly.

Biopsy of the gingival lesion showed whorls of spindle-shaped cells and leukocytic infiltration and neovascularization, with aberrant proliferation of small vessels; these findings were consistent with Kaposi sarcoma. The lesions initially responded to treatment with liposomal doxorubicin, but they reappeared after the patient became noncompliant with therapy.

Four months after the initial diagnosis, the patient was hospitalized for dyspnea. At that time, a CT scan of the chest showed extensive pulmonary nodules with fluffy, ill-defined margins (D). A CT scan of the abdomen revealed an enlarged liver with multiple attenuated foci. Liver biopsy was contraindicated because of severe thrombocytopenia (platelet count, 5000/µL). Idiopathic thrombocytopenic purpura was diagnosed based on the results of a bone marrow aspiration, which revealed an increased number of megakaryocytes, and a bone marrow biopsy, which showed normal marrow cellularity without evidence of hypoplasia or increased fibrosis. Hypoxemic respiratory failure, intractable hypotension, and coagulopathy subsequently developed, and the patient died.

Kaposi sarcoma is 15 times more frequent in men and appears to be more common in homosexual or bisexual men.^1,2 This low-grade vascular tumor is associated with human herpesvirus 8 infection. AIDS-related Kaposi sarcoma is the most common form in the United States.² The course is variable and ranges from minimal cutaneous disease to an explosive generalized form that involves the oral cavity and the GI and respiratory tracts.

Although a presumptive diagnosis of Kaposi sarcoma can often be made clinically, the confirmatory test is a biopsy. The differential diagnosis includes bacillary angiomatosis, hemangioma, purpura, dermatofibroma, pyogenic granuloma, and hematoma.

Current treatment options for systemic Kaposi sarcoma mainly consist of highly active antiretroviral therapy, liposomal anthracyclines, paclitaxel, and vinorelbine.^3,4 The prognosis is worse for patients with poor immune status and extensive systemic illness.⁵

References:

REFERENCES:1. Chang Y, Cesarman E, Pessin MS, et al. Identification of herpesvirus-like DNA sequences in AIDS-associated Kaposi's sarcoma. Science. 1994;266: 1865-1869.
2. Beral V, Peterman TA, Berkelman RL, Jaffe HW. Kaposi's sarcoma among persons with AIDS: a sexually transmitted infection? Lancet. 1990;335:123-128.
3. Nasti G, Errante D, Talamini R, et al. Vinorelbine is an effective and safe drug for AIDS-related Kaposi's sarcoma: results of a phase II study. J Clin Oncol. 2000;18:1550-1557.
4. Gill PS, Wernz J, Scadden DT, et al. Randomized phase III trial of liposomal daunorubicin versus doxorubicin, bleomycin, and vincristine in AIDS- related Kaposi's sarcoma. J Clin Oncol. 1996;14: 2353-2364.
5. Krown SE, Metroka C, Wernz JC. Kaposi's sarcoma in the acquired immune deficiency syndrome: a proposal for uniform evaluation, response, and staging criteria. J Clin Oncol. 1989;7:1201-1207.