KS Lesions (k + lesion)

Distribution by Scientific Domains

Selected Abstracts


Mehmet Bektas
A case of Kaposi's sarcoma (KS) in a 70-year-old man who was using corticosteroid for the treatment of asthma is presented. KS lesions occurred in the skin, colon, and rectum. Macroscopic appearances of the lesions varied from polypoid, hemorrhagic mucosal nodules and ulcers to red macules in the mucosal plane to plaque-like indurations of the wall. As the case was HIV negative, it is believed that KS developed due to corticosteroid-induced immunosuppression. [source]

Viral infections in the mouth

CG Teo
Oral hairy leukoplakia (OHL) and Kaposi's sarcoma (KS) are commonly encountered in the HIV-infected patient. A unique feature of OHL is non-cytolytic high level of replication of Epstein,Barr virus (EBV) in the glossal epithelium. The expression of viral-encoded anti-apoptotic proteins concomitant to replicative proteins probably underlies this phenomenon. The question of whether OHL arises from activation of EBV latent in the tongue, or from superinfection by endogenous EBV shed via non-glossal sites or by exogenous EBV remains unresolved. Human herpesvirus 8 (HHV8) is now seen as necessary but not sufficient cause of KS. Expression of HHV8-encoded oncogenic proteins in endothelial cells probably explains the aberrant proliferation of these cells in KS lesions. Studies into why KS is so commonly observed at the palate in HIV-infected patients may provide important clues to its pathogenesis. [source]

Mechanisms of expression of HHV8, EBV and HPV in selected HIV-associated oral lesions

JJ Hille
Opportunistic DNA viruses, particularly members of the herpesvirus family, are frequently the aetiological agents of HIV-associated oral lesions. Oral lesions common to the early phase of the AIDS epidemic, including Kaposi's sarcoma (KS), oral aphthous ulceration, AIDS-associated oral lymphoma, and oral hairy leukoplakia (OHL), have been tested for the prevalence of Epstein,Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV). While EBV DNA is detected by PCR in all of these lesions, abundant viral replication can only be detected in OHL. In OHL, a novel state of EBV infection has been discovered with concurrent expression of replicative and transforming proteins, with all of these proteins contributing to the development of the lesion. Activation of signalling pathways and up-regulation of the viral receptor, proliferative and antiapoptotic genes by these proteins induce several of the histological features common to OHL, such as acanthosis and hyperproliferation. In contrast to other permissive herpesvirus infections, expression of EBV transforming proteins within the permissively infected OHL tissue enables epithelial cell survival and may enhance viral replication. Detection of KSHV in these HIV-infected individuals has been localized only to their saliva. Replicative and latent KSHV gene products have been detected in association with the development of oral KS lesions. EBV, but not human cytomegalovirus (HCMV), has been detected by PCR in minor salivary gland biopsies of HIV-associated salivary gland disease. Human papillomaviruses (HPV) are associated with oral warts in HIV-positive individuals; a diagnosis that appears to be increasing in frequency in the era of highly active antiretroviral therapy. To date, there appears to be little increase in the incidence of HPV-associated oral cancer. The mechanisms of interaction between HIV and HPV are not fully understood. Expression of viral gene products is clearly important and necessary for the development of multiple AIDS-associated oral lesions. [source]

Human Herpesvirus-8 (HHV-8)-Associated Primary Effusion Lymphoma in two Renal Transplant Recipients Receiving Rapamycin

E. Boulanger
The Akt/mammalian target of rapamycin (mTOR) signaling cascade has been demonstrated to be constitutively activated in several malignancies, including Kaposi sarcoma (KS) and human herpesvirus-8 (HHV-8)-associated primary effusion lymphoma (PEL). In organ transplant recipients, therapeutic change from cyclosporin to the mTOR inhibitor rapamycin can lead to regression of KS lesions. Recent experiments using PEL cell lines and murine xenograft PEL models suggested that rapamycin could inhibit the growth of PEL cells. In the present report, we describe the cases of two HIV-1-negative males of African origin who underwent renal transplantation and developed PEL while receiving rapamycin as immunosuppressive treatment. Both patients were retrospectively found to be HHV-8 seropositive before renal transplantation. The present case report suggests that rapamycin may not protect HHV-8-infected renal transplant recipients from occurrence of PEL or progression of pre-existing PEL. [source]

The effects of human herpesvirus 8 infection and interferon-, response in cutaneous lesions of Kaposi sarcoma differ among human immunodeficiency virus-infected and uninfected individuals

F. Guedes
Summary Background, Kaposi sarcoma (KS) is associated with human herpesvirus 8 (HHV-8). The cutaneous immune response in this tumour is not well established and a better understanding is necessary. Objectives, To evaluate the HHV-8 expression and immune response in cutaneous lesions of classic KS (CKS) and AIDS-associated KS (AIDS-KS). Methods, We performed a quantitative immunohistochemical study of cells expressing HHV-8 latency-associated nuclear antigen (LANA), CD4, CD8 and interferon (IFN)-, in skin lesions from patients with CKS and AIDS-KS (with or without highly active antiretroviral therapy, HAART). Results, CKS showed higher LANA expression compared with AIDS-KS, regardless of HAART. We also found higher LANA expression in nodules compared with patch/plaque lesions. The tissue CD4+ cell proportion was lower in AIDS-KS patients without HAART than in patients with CKS. In CKS lesions, CD4+ and CD8+ cells expressed IFN-,, as shown by double immunostaining. AIDS-KS presented low numbers of IFN-,-expressing cells. CD8+ cell numbers were similar in all groups, which appeared unrelated to the clinical or epidemiological type of KS. Conclusions, Our quantitative data on the pattern of KS lesions in selected groups of patients, as shown by in situ immune response, demonstrated a CD4+ T-cell involvement associated with IFN-,, an environment of immune response-modified human immunodeficiency virus (HIV) infection. In our sample, the promotion of KS in patients without HIV appears to be related to higher HHV-8 load or virulence than in those with AIDS. This higher resistance may be explained by a sustained immune response against this herpesvirus, that is only partially restored but effective after HAART. [source]

Kaposi sarcoma of the musculoskeletal system

CANCER, Issue 6 2007
A review of 66 patients
Abstract Kaposi sarcoma (KS) of bone and skeletal muscle is unusual. In this report, the authors review 66 published patients with KS who had involvement of the musculoskeletal system reported from 1925 to 2006. In only 3 patients was acquired immunodeficiency syndrome (AIDS)-related KS identified within skeletal muscle. Osseous KS lesions were more frequent and occurred with African, classic, and AIDS-related KS and occurred rarely in transplantation-associated KS. Patients seldom were asymptomatic. They usually had bone pain with limited mobility or infrequently developed serious sequelae like spinal cord compression. Locally aggressive African and classic KS lesions typically involved the peripheral skeleton; whereas, in patients with AIDS, the axial (vertebrae, ribs, sternum, and pelvis) and/or maxillofacial bones more commonly were involved. Almost all patients had concomitant nonosseous KS lesions. Joint involvement was exceptional, and pathologic fractures were not observed. Computed tomography scans and magnetic resonance images were better at detecting osseous KS lesions, which frequently went undetected on plain x-ray films or bone scans. Pathologic diagnosis was important to exclude similar lesions like bacillary angiomatosis. Treatment options, including surgery and, in more recent patients, radiation and/or chemotherapy, had limited success. Cancer 2007 2007 American Cancer Society. [source]