Non-human immunodeficiency virus Kaposi's sarcoma can be effectively treated with low-dose interferon-alpha despite the persistence of herpesvirus-8

Demographic characteristics, treatment, and outcome of patients with Kaposi sarcoma: Ten-year follow-up results of a single center

BACKGROUND

Clinical features, types of Kaposi sarcoma, and treatment outcomes have not been well-defined in Turkey. In this study, we reviewed records of the patients who had been diagnosed with Kaposi sarcoma in the last decade in a single center and evaluated treatment results.

METHODS

Medical records of the Kaposi sarcoma patients seen in the last decade in a single tertiary center were evaluated in detail.

RESULTS

A total of 27 patients were identified; 18 patients had been checked for HHV8; and 16 of those patients were positive for HHV8. One patient was positive for HIV. Two patients having mycosis fungoides and myasthenia graves developed iatrogenic KS after immunosuppressive treatments. Interferon α was used in 21 patients; 8 patients achieved complete response; and 11 patients achieved a partial response. No serious side effects were observed. Systemic involvement did not develop in any patients except lymph node involvement in a patient with widespread skin lesions.

Diagnosis and Treatment of Kaposi Sarcoma

Kaposi sarcoma (KS) is the most common neoplasm of people living with HIV today. In Sub-Saharan Africa, KS is among the most common cancers in men, overall. Not only HIV-positive individuals present with KS; any immune compromised person infected with KS-associated herpesvirus (KSHV) or human herpesvirus 8 is at risk: the elderly, children in KSHV-endemic areas, and transplant recipients. KS diagnosis is based on detection of the viral protein latency-associated nuclear antigen (LANA) in the biopsy, but not all cases of KS are the same or will respond to the same therapy. Standard KS therapy has not changed in 20 years, but newer modalities are on the horizon and will be discussed.

Viruses

Viral infections are an important and often unrecognized component of disease in immunocompromised patients. The diagnosis and management of viral infections have expanded largely because of new quantitative molecular diagnostic assays. Well-recognized pathogens such as herpes simplex virus (HSV), cytomegalovirus (CMV), and respiratory viruses have been joined by newly recognized pathogens such as BK virus, human herpesvirus-6 (HHV-6), and human metapneumovirus in this highly susceptible patient population. The role of Epstein-Barr virus (EBV) and Human herpesvirus-8 (HHV-8) in lymphoproliferative diseases also continue to be clarified. As a result, the management of viral infections in patients with hematologic malignancies continues to be a growing challenge for the clinician.

Relationship between human herpesvirus 8 loads and disease stage in classic Kaposi sarcoma patients

Human herpesvirus 8 (HHV-8), also known as Kaposi sarcoma (KS)-associated herpesvirus, is causally implicated in all forms of KS, including the classic form. Our objective was to investigate the relationship between HHV-8 load in peripheral blood mononuclear cells (PBMCs) and the stage of the disease in classic KS (CKS) patients. HHV-8 loads were measured in 41 PBMC samples from CKS patients with different Krigel-based classification stages using a quantitative real-time polymerase chain reaction assay. Low HHV-8 DNA loads reaching a maximum of 75.5 copies/10(5) cells were detected in 73.2% of the patients. HHV-8 loads in patients with stages I and II were similarly distributed. An increased detection rate of HHV-8 DNA, although not statistically significant, was evident in patients diagnosed with CKS stages III and IV. We conclude that the measurements of HHV-8 load in PBMCs provide a limited correlation with the clinical stage of KS.

Efficacy of interferon-alpha for the treatment of Kaposi's sarcoma herpesvirus-associated uveitis

PURPOSE

To report cases of uveitis that are associated with human herpesvirus-8 (HHV-8) and the impact of interferon-alpha therapy on their visual outcome.

DESIGN

Interventional case reports.

METHODS

Extensive examination was performed in patients with chronic and severe uveitis to exclude a viral cause that requires specific therapy. After histopathologic, molecular, and/or serologic confirmation of HHV-8 uveitis, interferon-alpha2a therapy (3 millions IU/d, 3 days per week, subcutaneously) was initiated.

RESULTS

Two patients of Mediterranean origin were included. HHV-8 serologic result was positive in both cases. Histopathologic examination of conjunctival biopsy specimens confirmed Kaposi's sarcoma in the second case, and quantitative polymerase chain reaction identified HHV-8 DNA in the biopsy specimen. Disease was controlled by interferon-alpha2a in both cases, but maintenance therapy was mandatory to prevent relapses.

CONCLUSION

HHV-8-associated uveitis is a rare condition in immunocompetent hosts. Severe and chronic conditions may require antiviral and immunomodulatory therapies. Interferon alpha seems to be a good candidate and may be proposed in these cases.

Clearance of human herpesvirus 8 from blood and regression of leukopenia-associated aggressive classic Kaposi's sarcoma during interferon-alpha therapy: a case report

A human immunodeficiency virus-negative woman with severe classic Kaposi's sarcoma, idiopathic leukopenia, and massive spread of human herpesvirus 8 (HHV-8) in circulating cells showed stable disease remission in response to systemic interferon-alpha treatment that was accompanied by increased CD3(+) and CD4(+) T cell numbers and complete clearance of HHV-8 from the circulation. These results suggest a direct relationship between HHV-8 clearance from blood and regression of Kaposi's sarcoma and are consistent with the in vitro inhibitory effects of interferon-alpha on HHV-8 infection.

The interferons

The interferons are a group of naturally occurring biologic response modifiers that exhibit antiviral, antiproliferative, differentiating, and immune-enhancing properties. This interesting group of compounds has been found to be effective for the treatment of condylomata acuminata, skin cancers, high-risk melanoma, hepatitis C, mycosis fungoides, and keloid scars. The advantages of these agents must be weighed against their toxicities, the number of treatments, and cost.

Human Herpesvirus 8 Infections

Human herpesvirus 8 (HHV-8) or Kaposi's sarcoma (KS)-associated herpesvirus is a recently identified virus that is associated with KS, multicentric Castleman's disease, and body cavity-based lymphomas. KS is the most common kind of cancer in AIDS patients and the initial AIDS-defining condition in over 20% of patients. HHV-8 DNA has now been detected in over 95% of KS tissue samples supporting the concept that HHV-8 has a causal role in KS. The discovery has opened new avenues for understanding the epidemiology, pathogenesis, and treatment of KS and related conditions.