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

Kaposi Sarcoma of the Larynx: A Systematic Review

OBJECTIVE

Kaposi sarcoma (KS) of the larynx is a rare disease with few cases reported in the literature. This study aims to provide a comprehensive review of laryngeal KS, including patient characteristics, treatment, and clinical outcomes.

DATA SOURCES

PubMed, CINAHL, SCOPUS, and Cochrane Library.

REVIEW METHODS

A systematic review of the published English literature was conducted. An electronic search and bibliographic examination of articles pertaining to laryngeal KS were performed. Demographic data, tumor site, treatment strategies, follow-up, and outcome were analyzed.

RESULTS

A total 77 cases from 50 articles were included in the review. The mean age was 47.6 years (range, 8-81). There was an 8.6:1 male:female ratio. The most common presenting symptoms were dyspnea (n = 35) and hoarseness (n = 25). Laryngeal KS arose most frequently in the supraglottic region (n = 16). Chemotherapy alone (n = 27) was the most common treatment modality in patients with AIDS-associated KS, and surgical excision alone (n = 7) was most common in patients with other subtypes of KS (eg, classic, transplant associated). Average follow-up was 20.4 months (range, 0.75-120). Most patients with AIDS-associated KS died of other causes (n = 25), but most patients with other subtypes of KS were alive with no evidence of disease at follow-up (n = 13).

CONCLUSION

This review contains the largest pool of laryngeal KS cases to date. Long-term outcomes were generally unfavorable, often due to advanced HIV disease at the time of diagnosis.

Alpha interferon inhibits human herpesvirus 8 (HHV-8) reactivation in primary effusion lymphoma cells and reduces HHV-8 load in cultured peripheral blood mononuclear cells

Infection by human herpesvirus 8 (HHV-8) is associated with the development of Kaposi's sarcoma (KS). Since regression of KS can be achieved by treatment of the patients with alpha interferon (IFN-alpha), we analyzed the effects of IFN-alpha or anti-IFN-alpha antibodies (Ab) on HHV-8 latently infected primary effusion lymphoma-derived cell lines (BCBL-1 and BC-1) and on peripheral blood mononuclear cells (PBMC) from patients with all forms of KS and from at-risk subjects. IFN-alpha inhibited in a dose-dependent manner the amplification of HHV-8 DNA in BCBL-1 cells induced to lytic infection with tetradecanoyl phorbol acetate (TPA). This effect was associated with the inhibition of the expression of HHV-8 nut-1 and kaposin genes that are induced early and several hours, respectively, after TPA treatment. In addition, IFN-alpha inhibited virus production and/or release from BCBL-1 cells. Inhibition of nut-1 and kaposin genes by IFN-alpha was also observed in BC-1 cells induced with n-butyrate. Conversely, the addition of anti-IFN-alpha Ab to TPA-induced BCBL-1 cells resulted in a larger number of mature enveloped particles and in a more extensive cytopathic effect due to the neutralization of the endogenous IFN produced by these cells. IFN was also produced by cultured PBMC from HHV-8-infected individuals, and this was associated with a loss of viral DNA during culture. However, the addition of anti-IFN-alpha Ab or anti-type I IFN receptor Ab promoted the maintenance of HHV-8 DNA in these cells that was associated with the detection of the latency-associated kaposin RNA. Finally, the addition of IFN-alpha reduced the HHV-8 load in PBMC. Thus, IFN-alpha appears to have inhibitory effects on HHV-8 persistent infection of PBMC. These results suggest that, in addition to inhibiting the expression of angiogenic factors that are key to KS development, IFN-alpha may induce KS regression by reducing the HHV-8 load and/or inhibiting virus reactivation.

Kaposi's sarcoma of the larynx

Kaposi's sarcoma (KS) is a neoplastic vascular disorder, classically arising in the skin of the lower extremities. As a consequence of the acquired immunodeficiency syndrome (AIDS) epidemic, an increasing number of patients have been found to have KS. In AIDS patients, KS appears to exhibit a more diffuse nature and frequently affects the head and neck. Mucosal lesions are most often seen, commonly involving the oral cavity. Only rare cases of laryngeal involvement have been recorded in the literature. We report 2 cases of KS of the supraglottic larynx. Our first patient, an elderly man of Mediterranean descent, complained of voice change and throat discomfort. Endoscopy with biopsy for diagnosis allowed conservative treatment with chemotherapy. Our second patient was a younger man with AIDS who presented with symptoms of airway obstruction. Management with carbon dioxide laser epiglottectomy was successful in relieving that patient's symptoms. Although rare, KS may present in both healthy and immunocompromised patients, and must be considered in the differential diagnosis of all violaceous lesions of the larynx.