The emerging role of the human herpesvirus 8 (HHV8) in human neoplasia

Solitary eyelid Kaposi sarcoma in an HIV-negative patient

PURPOSE

To describe a case of localized Kaposi sarcoma (KS) of the eyelid in an HIV-seronegative patient.

METHODS

An 80-year-old man developed an ulcerated nodular tumor-like mass that grew rapidly on his left upper eyelid. There were no similar lesions elsewhere. The eyelid lesion was completely excised and histopathologically examined. Serological analyses and molecular biologic techniques, including polymerase chain reaction, were used.

RESULTS

Laboratory examinations were within normal limits, and serology for HIV was negative. Histological sections revealed a vascular proliferation composed predominantly of small slit-like blood vessels and epithelioid spindle cells, supporting the diagnosis of KS. Polymerase chain reaction was positive for human herpesvirus 8. During a 2-year follow-up, no recurrences, development of new lesions, or HIV seroconversions were observed.

CONCLUSION

This is a classic KS involving only the eyelid in an HIV-negative patient. Location in the eyelid is a possible, albeit rare, initial solitary manifestation of KS in elderly HIV-negative patients. Surgery is both safe and effective.

Lung cancer, a new challenge in the HIV-infected population

HIV infection predisposes patients to AIDS-defining malignancies, some of which, such as Kaposi's sarcoma and non-Hodgkin lymphoma, can affect the lungs. In 1996, AIDS-related mortality started to fall sharply in industrialized countries following the introduction of highly active antiretroviral treatments (HAART). This was accompanied by an increase in the proportion of deaths attributable to non AIDS-defining solid tumors, and especially lung cancer (LC). The increased risk of LC relative to the general population of the same age seems to be due partly to a higher prevalence of smoking among HIV-infected subjects. The average age of HIV-infected patients at LC diagnosis is about 45 years. Most patients are symptomatic at diagnosis and have only mild or moderate immunosuppression. LC is diagnosed when it is locally advanced or metastatic (stages III-IV) in 75-90% of cases, as in patients with unknown HIV serostatus. Adenocarcinoma is the most frequent histologic type. The prognosis of LC is poorer in HIV-infected patients than in the general population. Data on the efficacy and toxicity of chemotherapy in this setting are rare and rather imprecise. Surgery remains the reference treatment for localized disease in patients with adequate functional status and general health, regardless of their immune status. Prospective clinical trials are needed to define the optimal LC treatment strategies in HIV-infected patients.

Immunohistochemical detection of the human herpes virus 8 (HHV8) latent nuclear antigen-1 in Kaposi's sarcoma

AIMS

The molecular genetics of the human herpes virus 8 (HHV8) has now been characterised and the virus appears to be important in the pathogenesis of Kaposi's sarcoma (KS). This study attempts to determine the rate of HHV8 infection in KS in an Australian cohort.

METHODS

Routine streptavidin-biotin-peroxidase immunostaining with diaminobenzidine was performed on paraffin-embedded archival tissues of 37 KS cases using a murine monoclonal antibody directed against the C-terminus of the latent nuclear antigen-1 molecule of HHV8 (clone 13B10; Novocastra) at 1:50 dilution.

RESULTS

Positive HHV8 nuclear staining was detected in the nuclei of the spindle cells and endothelial cells of the vascular channels in about 78% (29/37) of all cases. HHV8 staining was absent in the non-neoplastic vessels in the adjacent tissue (P=0.0001, chi(2)=44.46; chi(2)-test with continuity correction) and the negative control cases of Merkel cell carcinoma (P=0.02, chi(2)=5.07; chi(2)-test with continuity correction). HHV8 staining was detected in 80% (8/10 cases) of the patch stage, 88% (7/8 cases) of the plaque stage and 74% (14/19 cases) of the late stage. No significant difference was found between HHV8 positivity and HIV status, age, gender, tumour recurrence, multiplicity or site of the lesions.

CONCLUSIONS

The latent nuclear antigen-1 of HHV8 can be detected by immunohistochemistry in the majority of human KS lesions, raising the possibility of its future potential use as an adjunct for the diagnosis of KS in problematic cases.

Bartholin's gland carcinoma, malignant melanoma and other rare tumours of the vulva

Non-squamous cancers of the vulva encompass an exciting and broad group of tumours, including Bartholin's gland carcinoma, malignant melanoma, Paget's disease, sarcomas and lymphoma. These tumours range from innocuous lesions treatable with simple local excision, such as basal-cell carcinoma, to cancers with very poor prognosis, such as Merkel-cell tumours. All of these tumours are thoroughly reviewed, with emphasis on presenting symptoms, pathological diagnosis and optimal management approaches. The literature supporting these recommendations is reviewed. Of the utmost importance in the management of these tumours is a thorough review of the pathological diagnosis by a specialist pathologist and a gynaecological oncologist. Establishing the correct diagnosis is essential to reaching appropriate treatment decisions. Frequently this will necessitate a second opinion by a referral centre.

Kaposi's sarcoma: clinico-pathological analysis of human immunodeficiency virus (HIV) and non-HIV associated cases

Kaposi s sarcoma (KS) is a angioformative lesion that classically occurs in elderly Eastern European and Mediterranean males but is also common in immunosuppressed individuals particularly human immunodeficiency virus (HIV)-infected patients. This study investigates the clinical and histopathological features of 47 patients with Kaposi s sarcoma from a teaching hospital in Sydney, Australia, in which 44 cases had adequate clinical follow-up information over a 10-year period. Most of the lesions were of late stage (37/47 cases; 79%), consisting of 11 cases of plaque stage KS and 26 cases of nodular stage KS with only 10 cases of early or patch stage KS. The majority of the HIV-positive cases (23/33; 70%) and all of the HIV-negative (14/14; 100%) cases had late stage lesions (p=0.020; X 2 -test). The histopathological features that were more common in the KS lesions of HIV-negative patients were lesional cell mitosis (p=0.0002), single cell necrosis (p=0.001), apoptosis (p=0.0001) and single cell anaplasia (p=0.0001). The KS lesions in HIV-positive patients tended to have dissecting blood vessels (14/33 cases; 42%) unlike those seen in HIV-negative patients (0/14 cases; 0%) (p=0.004). Most HIV-positive cases (30/33; 90%) were males (p=0.0068); and all these patients (33/33 cases; 100%) were <60 years old, in contrast to HIV-negative patients (1/11 cases; 9%) (p=0.0001). HIV status does not affect the occurrence of multiplicity of KS lesions. However, extracutaneous or visceral KS lesions were more likely to occur in HIV-positive patients (p=0.027). The number of cases of histologically proven KS cases has decreased markedly over the recent 5 year period of 1995-1999 (n=14), which was less than half of the number of the preceding 5 year period, 1990-1994 (n=33). In summary, there are distinct differences in the clinical and histopathological features of Kaposi s sarcoma lesions in HIV-positive and HIV-negative patients. Despite the recent discovery of the HHV8 virus as the initiating and promoting factor of most of the KS lesions, these differences indicated that there might be different mechanisms that occur in HIV-positive and HIV-negative patients in the development of this lesion.