Kaposi's sarcoma

Kaposi sarcoma-associated herpesvirus complement control protein (KCP) and glycoprotein K8.1 are not required for viral infection in vitro or in vivo

Kaposi sarcoma-associated herpesvirus (KSHV), also known as human herpesvirus-8, is the causal agent of Kaposi sarcoma, a cancer that appears as tumors on the skin or mucosal surfaces, as well as primary effusion lymphoma and KSHV-associated multicentric Castleman disease, which are B-cell lymphoproliferative disorders. Effective prophylactic and therapeutic strategies against KSHV infection and its associated diseases are needed. To develop these strategies, it is crucial to identify and target viral glycoproteins involved in KSHV infection of host cells. Multiple KSHV glycoproteins expressed on the viral envelope are thought to play a pivotal role in viral infection, but the infection mechanisms involving these glycoproteins remain largely unknown. We investigated the role of two KSHV envelope glycoproteins, KSHV complement control protein (KCP) and K8.1, in viral infection in various cell types in vitro and in vivo. Using our newly generated anti-KCP antibodies, previously characterized anti-K8.1 antibodies, and recombinant mutant KSHV viruses lacking KCP, K8.1, or both, we demonstrated the presence of KCP and K8.1 on the surface of both virions and KSHV-infected cells. We showed that KSHV lacking KCP and/or K8.1 remained infectious in KSHV-susceptible cell lines, including epithelial, endothelial, and fibroblast, when compared to wild-type recombinant KSHV. We also provide the first evidence that KSHV lacking K8.1 or both KCP and K8.1 can infect human B cells in vivo in a humanized mouse model. Thus, these results suggest that neither KCP nor K8.1 is required for KSHV infection of various host cell types and that these glycoproteins do not determine KSHV cell tropism.

IMPORTANCE

Kaposi sarcoma-associated herpesvirus (KSHV) is an oncogenic human gamma-herpesvirus associated with the endothelial malignancy Kaposi sarcoma and the lymphoproliferative disorders primary effusion lymphoma and multicentric Castleman disease. Determining how KSHV glycoproteins such as complement control protein (KCP) and K8.1 contribute to the establishment, persistence, and transmission of viral infection will be key for developing effective anti-viral vaccines and therapies to prevent and treat KSHV infection and KSHV-associated diseases. Using newly generated anti-KCP antibodies, previously characterized anti-K8.1 antibodies, and recombinant mutant KSHV viruses lacking KCP and/or K8.1, we show that KCP and K8.1 can be found on the surface of both virions and KSHV-infected cells. Furthermore, we show that KSHV lacking KCP and/or K8.1 remains infectious to diverse cell types susceptible to KSHV in vitro and to human B cells in vivo in a humanized mouse model, thus providing evidence that these viral glycoproteins are not required for KSHV infection.

Anaplastic Kaposi Sarcoma of the Right Colon, in a Young Man With Acquired Immunodeficiency Syndrome: A Rare Variant in an Unreported Organ

Kaposi sarcoma (KS) arises in the context of 4 epidemiologic-clinical settings: Classic, endemic, epidemic, and iatrogenic; the most serious types are endemic and epidemic, and visceral involvement occurs mostly in the latter. Several morphological variants of KS have been described, of which the anaplastic one is highly aggressive. We report the case of an anaplastic KS arising from the ascending colon in a 32-year-old human immunodeficiency virus (HIV)-positive male patient with a 6-year history of multiple mucocutaneous KS. Anaplastic KS is most frequent in endemic and classic settings; there are ten cases of anaplastic KS reported in HIV-positive male patients. There is now strong evidence that KS is a clonal neoplasm characterized by chromosomal instability at the molecular level. According to the morphological spectrum and contemporary hypotheses of oncogenesis, conventional KS should be considered an incipient endothelial neoplasia, multiple or single, and anaplastic KS, the fully developed stage of the malignant neoplasm.

Electrochemotherapy in Kaposi's Sarcoma Patients: From the Gold Standard Strategy to Locally Advanced Cutaneous and Subcutaneous Lesions

Electrochemotherapy (ECT) is one of the newest therapeutic strategies employed as a medical procedure for skin neoplasms' treatment, especially for classic Kaposi's sarcoma (CKS). The aim of this study was to demonstrate ECT clinical response and the local control of CKS disease. The primary endpoint was to value the worth and efficacy of this local therapy in CKS skin lesions' treatment. In total, 19 CKS patients were enrolled, 14 males and 5 females with median age at diagnosis of 72. Complete response (CR) has been gained in 12 patients after first ECT attempt; meanwhile, 3 and 4 out of 19 patients obtained a partial response (PR), so they underwent a second and third ECT treatment, respectively. Clinical response was evaluated during the entire timeframe of the follow-up, which ranged between 3 months and 4 years with a median of 18 months. The control of CKS skin lesions still represents a challenge for surgeons and oncologists. Nevertheless, according to this and other authors' recent experiences, ECT could be considered the gold standard strategy for early-stage patients, but at the same time it could be considered as a valid option in controlling Kaposi's sarcoma locally advanced lesions.

KSHV (HHV8) vaccine: promises and potential pitfalls for a new anti-cancer vaccine

Seven viruses cause at least 15% of the total cancer burden. Viral cancers have been described as the "low-hanging fruit" that can be potentially prevented or treated by new vaccines that would alter the course of global human cancer. Kaposi sarcoma herpesvirus (KSHV or HHV8) is the sole cause of Kaposi sarcoma, which primarily afflicts resource-poor and socially marginalized populations. This review summarizes a recent NIH-sponsored workshop's findings on the epidemiology and biology of KSHV as an overlooked but potentially vaccine-preventable infection. The unique epidemiology of this virus provides opportunities to prevent its cancers if an effective, inexpensive, and well-tolerated vaccine can be developed and delivered.

Kaposi Sarcoma with Mucocutaneous Involvement in French Guiana: An Epidemiological Study between 1969 and 2019

Data on Kaposi sarcoma in French Guiana are scarce and out of date. This territory presents unique epidemiological features. The objectives of this retrospective study were to analyse the clinical features, outcome and incidence of the different forms of Kaposi sarcoma in patients diagnosed between 1969 and 2019. The study population comprised a total of 52 patients. Clinical forms included epidemic Kaposi sarcoma (n=30), endemic (n=18), iatrogenic (n=2), classic (n=1) and unclassified Kaposi sarcoma (n=1). The mean annual incidence rate of epidemic Kaposi reached a peak in the 1990s (0.93/100,000) then decreased in the 2000s (0.33/100,000), while the incidence of endemic Kaposi sarcoma reached a peak in the 1980s (0.82/100,000) before decreasing in the 2000s (0.12/100,000). Factors associated with the epidemic form were: sexual intercourse between men (p=0.0054) and Haitian origin (p=0.035). The presence of nodules and/or tumour, lesions limited to the lower limbs, and age >65 years were associated with the endemic form. While Creole populations seem to be as affected by endemic Kaposi sarcoma as their African counterparts, the dynamics of Kaposi sarcoma in French Guiana are now dominated by the epidemic form.

Diagnosis and treatment of classic and iatrogenic Kaposi's sarcoma: Italian recommendations

Kaposi's sarcoma (KS) is a lymphangioproliferative disorder associated with Human herpesvirus 8 (HHV8) infection. Four clinical subtypes are recognized: classic, endemic, epidemic (HIV-related) and iatrogenic. KS diagnosis is based on clinical features, histopathological assessment, and HHV8 serology. Classic KS is usually skin-limited and has a chronic course, while the iatrogenic variant may show mucosal, nodal or visceral involvement. Clinical staging is fundamental to guide the management. Localized disease may be treated with different local therapies, even if there are no randomized trials comparing these different modalities. Aggressive, disseminated KS and cases with visceral involvement usually require systemic chemotherapy, most commonly vinblastine, bleomycin or paclitaxel. Iatrogenic KS needs immunosuppression tapering/withdrawal and, if possible, switch to m-TOR inhibitors in post-transplant KS. The present work by a panel of Italian experts provides guidelines on KS diagnosis and management based on a critical review of the literature and a long and extensive personal experience.

A case of classic Kaposi sarcoma in an immunocompetent human immunodeficiency virus-negative Dominican man

Kaposi sarcoma is an uncommon tumor that primarily arises in the skin and mucosal surfaces, but may metastasize to the internal organs. Four main variants of Kaposi sarcoma are recognized as the following: classic Kaposi sarcoma, which occurs in middle-aged or elderly men; epidemic Kaposi sarcoma, associated with human immunodeficiency virus infection; iatrogenic Kaposi sarcoma seen in patients on immunosuppressive drug therapy; and endemic Kaposi sarcoma. This report is of a case of classic Kaposi sarcoma in 55-year-old immunocompetent and human immunodeficiency virus-negative Dominican man who had lived in the United States for 2 years, who presented with a 2-year history of skin lesions on his lower extremities and soft palate. Biopsy of the soft palate was consistent with Kaposi sarcoma. The patient was treated with paclitaxel with a good response. This case report demonstrates the importance of recognizing that classic Kaposi sarcoma, first described almost 150 years ago, can still present in immunocompetent middle-aged men of all ethnicities.

Kaposi Sarcoma in Association With an Extracavitary Primary Effusion Lymphoma Showing Unusual Intravascular Involvement: Report of a Case Harboring a FAM175A Germline Mutation

Primary effusion lymphoma (PEL) is a rare form of aggressive B-cell lymphoma characterized by a malignant serous effusion involving body cavities. It usually associated with human herpes virus-8 (HHV-8) and coexpression of Epstein-Barr virus and mostly affects patients with HIV. We report a rare case of cutaneous PEL with an unusual intravascular presentation, combined with Kaposi sarcoma involving the skin, lung, and gastrointestinal tract. The molecular genetic analysis of the sarcoma and lymphoma components, using next-generation sequencing was performed. The patient was a 67-year-old man who presented with multiple cutaneous tumors and mass in the left lung. He died 17 hours after the admission to the hospital. At autopsy, in addition to the cutaneous lesions, tumors in the left lung and gastrointestinal mucosa were detected, and no effusions in the body cavities were seen. The biopsy from the cutaneous lesions, pulmonary, and intestinal tumors revealed histological and immunohistochemical features of Kaposi sarcoma. In addition, the skin biopsy specimens contained a diffuse infiltrate composed of large pleomorphic cells, with focal intravascular growth that were negative for pan B-cell markers, weakly positive for CD38 and CD138 but expressed CD3, HHV-8, and Epstein-Barr virus. Molecular genetic studies in this specimen revealed monoclonal rearrangements of the IgH gene. The diagnosis of PEL, solid variant, was made. Next-generation sequencing analysis of the tumorous and normal tissue detected a pathogenic germline mutation of the FAM175A gene and somatic mutations in BRCA2 and RAD51B (in both sarcoma and lymphoma specimens), and INPP4B and RICTOR (in lymphoma specimen only).

Anaplastic Kaposi's Sarcoma of the Adrenal in an HIV-negative Patient With Literature Review

Kaposi's sarcoma (KS) is a peculiar tumor of viral etiology, with the HHV8 rhadinovirus playing a fundamental role in its development. Several epidemiological categories of KS have been identified, of which the sporadic, endemic, iatrogenic, and the epidemic are the main ones. Several histologic disease morphologies have been described, such as inflammatory, angiomatous, spindle cell, mixed, and the anaplastic (sarcomatous) subtypes. The skin of the limbs is most commonly affected, but any other organ or site may be involved. Microscopically KS may enter the differential diagnosis with several different entities, and for this purpose the immunohistochemical detection of the viral latent nuclear antigen-1 (LNA-1) may be crucial. Sporadic KS is usually benign, but rarely it may be aggressive. Anaplastic histology heralds an ominous course in any clinical context. We report a case of anaplastic retroperitoneal KS, occurring in an HIV-negative adult man. This patient presented with a huge left suprarenal mass, which was totally resected, and initially diagnosed as inflammatory leiomyosarcoma, because of the monomorphic spindle cell tumor morphology. After 12 years the tumor recurred locally as an unresectable mass, which was biopsied and examined. At the time of recurrence, the histologic slides of the primary tumor were reviewed, and the previous diagnosis was changed to that of atypical KS. Histologically the recurrent tumor showed both spindle cell and epithelioid appearances. Strongly diffuse HHV8/LAN-1 immunopositivity was documented in both tumors. The final diagnosis for the entire case was anaplastic KS. Then, the patient died in a few months.

Primary Nasopharyngeal Kaposi Sarcoma as Index Diagnosis of AIDS in a Previously Healthy Man

A 38-year-old, previously healthy man presented with blood-stained saliva and epistaxis. A 3 mm nasopharyngeal lesion was found. A biopsy was performed and microscopic examination revealed a Kaposi sarcoma. The patient was subsequently found to be positive for human immunodeficiency virus (HIV). The diagnosis of Kaposi sarcoma in the presence of HIV infection advanced his disease to Acquired Immunodeficiency Syndrome (AIDS). Primary manifestation of Kaposi sarcoma in the nasopharynx is extremely rare. The histologic differential diagnosis of Kaposi sarcoma in this unusual site, especially without the clinical history of immunosuppression, is broad. Awareness that nasopharynx can be a primary involvement site of Kaposi sarcoma and serves as index diagnosis of AIDS is important given its serious clinical implication.

Kaposi's Sarcoma: A Clinico-Pathologic Overview

A careful overview of the classical appearances of Kaposi's sarcoma (KS) as well as of its variants were reviewed from the clinical and pathological point of view. The growth phases (stages) and the cellular patterns were histopathologically compared with emphasis on the developmental progression of disease as well as mitotic activity. Other morphological aspects were also assessed such as the features of the early phases and the incidence of hyaline bodies. One hundred and forty-three lesions from 96 patients mostly of the Italian sporadic type were investigated. A complete list of those entities which should be considered in differential diagnosis is shown and the dilemma of whether KS is a neoplasia or a hyperplasia is discussed.

Histopathology of Spindle Cell Vascular Tumors

Vascular tumors with a spindled morphology represent a diagnostic challenge in soft tissue pathology. It may be difficult to distinguish certain benign entities in this category from spindled vascular tumors of intermediate malignancy or even spindled variants of angiosarcoma. This article focuses on vascular tumors characterized by a predominantly spindled morphology, including spindle cell hemangioma, acquired tufted angioma (angioblastoma of Nakagawa), kaposiform hemangioendothelioma, Kaposi sarcoma, and spindle cell variants of angiosarcoma.

Gastrointestinal tract spindle cell lesions--just like real estate, it's all about location

Interpretation of gastrointestinal tract mesenchymal lesions is simplified merely by knowing in which anatomic layer they are usually found. For example, Kaposi sarcoma is detected on mucosal biopsies, whereas inflammatory fibroid polyp is nearly always in the submucosa. Gastrointestinal stromal tumors (GISTs) are generally centered in the muscularis propria. Schwannomas are essentially always in the muscularis propria. Mesenteric lesions are usually found in the small bowel mesentery. Knowledge of the favored layer is even most important in interpreting colon biopsies, as many mesenschymal polyps are encountered in the colon. Although GISTs are among the most common mesenchymal lesions, we will concentrate our discussion on other mesenchymal lesions, some of which are in the differential diagnosis of GIST, and point out some diagnostic pitfalls, particularly in immunolabeling.

Cyclooxygenase-2-prostaglandin E2-eicosanoid receptor inflammatory axis: a key player in Kaposi's sarcoma-associated herpes virus associated malignancies

The role of cyclooxygenase-2 (COX-2), its lipid metabolite prostaglandin E2 (PGE2), and Eicosanoid (EP) receptors (EP; 1-4) underlying the proinflammatory mechanistic aspects of Burkitt's lymphoma, nasopharyngeal carcinoma, cervical cancer, prostate cancer, colon cancer, and Kaposi's sarcoma (KS) is an active area of investigation. The tumorigenic potential of COX-2 and PGE2 through EP receptors forms the mechanistic context underlying the chemotherapeutic potential of nonsteroidal anti-inflammatory drugs (NSAIDs). Although role of the COX-2 is described in several viral associated malignancies, the biological significance of the COX-2/PGE2/EP receptor inflammatory axis is extensively studied only in Kaposi's sarcoma-associated herpes virus (KSHV/HHV-8) associated malignancies such as KS, a multifocal endothelial cell tumor and primary effusion lymphoma (PEL), a B cell-proliferative disorder. The purpose of this review is to summarize the salient findings delineating the molecular mechanisms downstream of COX-2 involving PGE2 secretion and its autocrine and paracrine interactions with EP receptors (EP1-4), COX-2/PGE2/EP receptor signaling regulating KSHV pathogenesis and latency. KSHV infection induces COX-2, PGE2 secretion, and EP receptor activation. The resulting signal cascades modulate the expression of KSHV latency genes (latency associated nuclear antigen-1 [LANA-1] and viral-Fas (TNFRSF6)-associated via death domain like interferon converting enzyme-like- inhibitory protein [vFLIP]). vFLIP was also shown to be crucial for the maintenance of COX-2 activation. The mutually interdependent interactions between viral proteins (LANA-1/vFLIP) and COX-2/PGE2/EP receptors was shown to play key roles in the biological mechanisms involved in KS and PEL pathogenesis such as blockage of apoptosis, cell cycle regulation, transformation, proliferation, angiogenesis, adhesion, invasion, and immune-suppression. Understanding the COX-2/PGE2/EP axis is very important to develop new safer and specific therapeutic modalities for KS and PEL. In addition to COX-2 being a therapeutic target, EP receptors represent ideal targets for pharmacologic agents as PGE2 analogues and their blockers/antagonists possess antineoplastic activity, without the reported gastrointestinal and cardiovascular toxicity observed with few a NSAIDs.

Classic Kaposi's sarcoma in Morocco: clinico-epidemiological study at the National Institute of Oncology

BACKGROUND

Classic Kaposi's sarcoma (CKS) is a rare disease likely associated with human herpes virus 8 (HHV-8) infection, and occurs predominantly in Jewish, Mediterranean and middle eastern men. There is a dearth of data in Moroccan patients with CKS regarding epidemiology, clinical characteristics and outcomes. This report examines a cohort of patients with CKS evaluated at the national institute of oncology over 11-year period.

METHODS

A retrospective analysis of patients referred to the national institute of oncology with classical Kaposi sarcoma, between January 1998 and February 2008, was performed. Reviewed information included demographics, clinical and pathological staging, death or last follow-up.

RESULTS

During the study period, 56 patients with a diagnosis of CKS have been referred to our hospital. There were 11 (19.7%) females and 45 (80.3%) males (male-to-female ratio: 4:1). Mean age at diagnosis was 61.7 ± 15 (range: 15-86 years). Nodules and/or plaques were the most frequent type of lesion. The most common location was the lower limbs, particularly the distal lower extremity (90%). In addition to skin involvement, visceral spread was evident in 9 cases. The most common visceral involvement sites were lymph nodes (44%), lung (22%), and gastrointestinal tract (22%). Associated lymphoedema was seen in 24 (42%) of the patients. There were 18 stage I patients (32.14%), 8: stage II (14.28%), 21 stage III (37.5%) and 9 stage IV (16.07%). A second primary malignancy was diagnosed in 6 cases (10.7%), none of the reticuloendothelial system. With a median follow-up of 45 months, 38 (67.8) patients are alive, of whom 25 (65.78%) patients with stable disease, five with progressive disease currently under systemic chemotherapy and 8 (21.05%) are alive and free of disease, over a mean interval of 5 years.

CONCLUSION

This is the largest reported series in our context. In Morocco, CKS exhibits some special characteristics including a disseminated skin disease at diagnosis especially in men, a more common visceral or lymph node involvement and a less frequent association with second malignancies.

Primary vascular tumors of the lungs: a review

Unlike their counterparts in other organ systems, primary vascular neoplasms of the lung are rare. Most of these lesions have only been reported as isolated case studies or small series. When dealing with malignant lesions, metastasis from extrapulmonary sites will have to be excluded before a primary location in the lungs can be confirmed. In this review, the clinicopathologic, immunophenotypical, ultrastructural, and molecular biologic characteristics of primary vascular tumors of the lungs are discussed. The tumoral conditions that will be addressed include hemangioma, lymphangioma, epithelioid hemangioendothelioma, angiosarcoma, and Kaposi's sarcoma. Their respective differential diagnoses will also be discussed.

Kaposi sarcoma: a continuing conundrum

Kaposi sarcoma (KS) remains a challenge. Its classic or Mediterranean form tends to be benign. In transplant recipients it may be less so. As part of the AIDS pandemic, of which it was an original defining component, it may be life-threatening. It is due to human herpesvirus-8, which is necessary but not sufficient to produce the disease. KS has a low prevalence in the general population of the United States and United Kingdom, with an intermediate rate in Italy and Greece, and a high one in parts of Africa. In Italy, hot spots include its southern regions, the Po River Valley, and Sardinia, possibly related to a high density of blood-sucking insects. An important challenge is to treat KS patients without immunocompromising them. The potential of effective anti-herpes virus therapy and the use of sirolimus in transplantation recipients have added new opportunities for KS prevention.

LEARNING OBJECTIVES

At the conclusion of this learning activity, participants should be able to provide the most recent information about Kaposi sarcoma in the context in which it occurs. Its classic or Mediterranean form, its pattern in transplant recipients and others iatrogenically immunosuppressed, and its occurrence as a potentially life-threatening part of the AIDS pandemic will be stressed. Its etiology and transmission will be discussed in detail to facilitate understanding of Kaposi sarcoma and of human herpesvirus-8 infection in the general population of the United States and United Kingdom, in Italy and Greece, and in certain parts of Africa. Its therapy, including the concept of doing it without immunocompromising the patient, will be stressed. New opportunities for Kaposi sarcoma prevention will also be discussed.

Histological variants of cutaneous Kaposi sarcoma

This review provides a comprehensive overview of the broad clinicopathologic spectrum of cutaneous Kaposi sarcoma (KS) lesions. Variants discussed include: usual KS lesions associated with disease progression (i.e. patch, plaque and nodular stage); morphologic subtypes alluded to in the older literature such as anaplastic and telangiectatic KS, as well as several lymphedematous variants; and numerous recently described variants including hyperkeratotic, keloidal, micronodular, pyogenic granuloma-like, ecchymotic, and intravascular KS. Involuting lesions as a result of treatment related regression are also presented.

Kaposi sarcoma in unusual locations

Kaposi sarcoma (KS) is a multifocal, vascular lesion of low-grade malignant potential that presents most frequently in mucocutaneous sites. KS also commonly involves lymph nodes and visceral organs. This article deals with the manifestation of KS in unusual anatomic regions. Unusual locations of KS involvement include the musculoskeletal system, central and peripheral nervous system, larynx, eye, major salivary glands, endocrine organs, heart, thoracic duct, urinary system and breast. The development of KS within wounds and blood clots is also presented. KS in these atypical sites may prove difficult to diagnose, resulting in patient mismanagement. Theories to explain the rarity and development of KS in these unusual sites are discussed.

Classic Kaposi Sarcoma in the United States over the last two decades: a clinicopathologic and molecular study of 438 non-HIV-related Kaposi Sarcoma patients with comparison to HIV-related Kaposi Sarcoma

Classic Kaposi sarcoma is rare and occurs predominantly in Mediterranean and Middle Eastern men. Since the emergence of acquired immune deficiency syndrome (AIDS)-related Kaposi sarcoma, the incidence, clinicopathologic features, and molecular human herpesvirus 8 (HHV-8) association of American Classic Kaposi Sarcoma has not been fully explored. This study compares Classic Kaposi Sarcoma to AIDS-related Kaposi Sarcoma over the same two decade time period. There were 438 histologically and clinically confirmed Classic Kaposi Sarcoma patients. The ethnic/racial distribution included Caucasian/American (56%), Mediterranean (22%), South American Hispanic (18%), Black (10%), western European (4%), Middle East (4%), Scandinavian (2%), and other (2%). Classic Kaposi Sarcoma was more common in men, 7:1, with a mean age of 74 years. The lesions presented in the lower extremity (69%), in the nodular stage (83%), and HHV-8 was detected by PCR in 40/41 randomly selected cases. A second, non-Classic Kaposi Sarcoma, malignancy was present in 42% (n=45) of the 108 Classic Kaposi Sarcoma patients with complete clinical information, 73% (33 patients) with a higher incidence over the general population. Follow-up of <1-19 years (mean=4.8 years) revealed that 24% of patients died of second malignancy, 22% died of other medical conditions, 2% died of treatment-related complications, and 2% patients died of widespread disease. Thirty-five percent are alive with no evidence of disease and 15% with persistent disease. Human immunodeficiency virus-related Kaposi Sarcoma was observed in 354 cases. There was a male predominance and more aggressive behavior, with higher rates of visceral and disseminated disease. While Classic Kaposi Sarcoma in the United States is an indolent disease and rarely accounts for patient demise, predominantly affecting Caucasian/American males on the lower extremity in the nodular phase, it more importantly may denote an underlying other malignancy. Current PCR probes detect HHV-8 in 98% of Classic Kaposi Sarcoma cases. In comparison, AIDS-related Kaposi Sarcoma is predominately multicentric, visceral, and disseminated, with more aggressive behavior.

Epidemiological and clinical characteristics of classic Kaposi's sarcoma in Peru

BACKGROUND

Classic Kaposi sarcoma (KS) occurs predominantly among the elderly, with predominance among Jews, Italians, and Greeks. Classic KS has been seen relatively frequently in Peru.

OBJECTIVE

Our purpose was to outline the epidemiological and clinical profile of classic KS in Peru.

METHODS

Epidemiological and clinical features of all classic KS cases diagnosed between 1969 and 2003 at Hospital Nacional Cayetano Heredia (HNCH) and between 1946 and 2004 at Instituto Nacional de Enfermedades Neoplasicas (INEN) were reviewed and studied retrospectively.

RESULTS

An overall incidence of 2.54 per 10,000 attended patients was obtained at the INEN during the 48-year period (mean, 2.39; standard deviation: 1.99; 95% confidence interval, 2.92-1.86). Twenty-one cases were discovered at HNCH and 106 cases at INEN. A male/female ratio of 2.62:1 was found. Mean age at diagnosis was 68.5 years. Lower limbs were involved in 109 patients (85.8%); the trunk was involved in 11 patients (8.6%). Nodules were the most common type of lesion (85.8%); less commonly found were plaques (27.5%), macules (12.5%), papules (12.5%), and ulcers (8.6%). Sixty-two patients had no symptoms (48.8%). Pain was the most common symptom (26.7%), followed by edema (21.2%), bleeding (14.9%), and pruritus (3.9%). A second primary malignancy was found in 11 patients (8.6%).

LIMITATIONS

These results were obtained from patients with classic KS in Peru and may not be applicable to other populations.

CONCLUSION

Classic KS is quite common in Peru with sporadic cases found throughout the country and some clustering in the coastal region. Classic KS in Peru has a clinical presentation that is very similar, but not identical, to the classic KS described in the Mediterranean region, exhibiting some special clinical and epidemiological characteristics with a nodular, nonsymmetric presentation that usually affects the lower extremities.

Kaposi's sarcoma in kidney transplant recipients: a 23-year experience

BACKGROUND

Kaposi's sarcoma (KS) is a relatively common malignancy after kidney transplantation, accounting for up to 80% of all malignancies in developing countries.

AIM

To assess the frequency of KS in renal transplant recipients, and determine the impact of demographic factors, immunosuppression and treatment options.

DESIGN

Retrospective study in a single centre in South Africa.

METHODS

Charts and pathology reports of 542 recipients of 623 kidney allografts treated at our institution between 1976 and 1999 were reviewed.

RESULTS

After a mean follow-up of 6.4 years, 21 (3.9%) recipients had KS, representing 47.7% of all post-transplant malignancies. KS accounted for more post-transplant cancers in non-White than White patients (79.1% vs. 11.7%, p < 0.001). KS was equally common in males and females, and was not more frequent under cyclosporine. Skin involvement was universal; visceral disease occurred in six patients (28.6%). Sixteen (94.1%) patients with limited skin disease and two (100%) with superficial nodal disease responded to withdrawal or reduction of immunosuppression. Renal function was preserved when immunosuppression was reduced instead of withdrawn (p = 0.02). Patients with vital organ involvement succumbed rapidly to KS. Post-mortem examination revealed more extensive disease than was suspected clinically.

DISCUSSION

Ethnic differences exist in the frequency of KS in patients residing in the same geographical area. Since withdrawal results in graft loss, reducing immunosuppression should be first-line treatment for patients with disease limited to skin, and possibly for disease of the superficial lymph nodes. The malignant behaviour of KS, and extent of pathological involvement, cast doubt on the idea that KS is a hyperplasia rather than a true malignancy.

Vascular tumors of the skin: A selective review

Cutaneous vascular proliferations are a vast and complex spectrum. Many appear as hamartomas in infancy; others are acquired neoplasms. Some vascular proliferations are hyperplastic in nature, although they mimic hemangiomas, i.e., neoplasms. The vast majority of the vascular lesions are hemangiomas. Between the hemangiomas and frankly angiosarcomas, there is a group of neoplasms that are angiosarcomas, albeit ones of low grade histologically and, probably, biologically. The term "hemangioendothelioma" has been created to encompass these neoplasms. Vascular proliferations are, fundamentally, composed of endothelial cells. Some hemangiomas, however, contain also abundant pericytic, smooth muscle, or interstitial components, or a combination of them. These heterogeneous cellular components are present usually in hemangiomas. Some of the newly described vascular proliferations, however, are difficult to differentiate from some of the angiosarcomas. Others are markers, occasionally, of serious conditions such as Fabry's Disease (angiokeratoma) and POEM's syndrome (glomeruloid hemangioma). Kaposi's sarcoma continues to be an enigma. The demonstration of Herpes virus 8 in this condition raises doubt about its neoplastic nature. The demonstration of endothelial differentiation of its nodular lesions is tenuous and its true nature remains unresolved. While physicians have known about post-mastectomy angiosarcomas from the origin of the radical mastectomy, a new group of unusual vascular proliferations of the mammary skin are being defined. These lesions arise in the setting of breast-conserving surgical treatment with adjuvant radiation therapy. The incubation period is usually 3 to 5 years, in contrast with the 10, or more, in classical cases of post-mastectomy angiosarcoma. These lesions usually are subtle, both clinically and histologically, in contrast with the "classical," dramatic presentation of mammary angiosarcoma. The spectrum of findings ranges from "simple" lymphangiectasia-like vascular proliferations to unequivocal angiosarcomas. The pathogenesis of these lesions remains a mystery. There are very few clues that allow one to separate hemangiomas from angiosarcomas. The presence of heterologous cellular elements and, particularly, well-developed smooth muscle components tends to favor a hemangioma. Similarly, the presence of thrombosis usually supports hemangioma. Nevertheless, there are no unequivocal or reliable individual diagnostic criteria. A thorough knowledge of the different conditions and their differential diagnoses eventually leads to the proper diagnosis in most cases.

Kaposi's sarcoma: aetiopathogenesis, histology and clinical features

Kaposi's sarcoma (KS) represents today one of the most common skin cancers in transplanted Mediterranean subjects and, since the epidemic of human immunodeficiency virus/acquired immune deficiency syndrome, in young unmarried single men. The disease has been associated with the recent identified human herpesvirus (HHV)-8 or KS herpesvirus and its incidence in the general population shows a north to south gradient that parallels the HHV-8 increasing prevalence from Nordic countries to sub-Saharan regions. The identification of the aetiopathogenetic mechanisms (viral agents and immunodeficiency) involved in the pathogenesis of KS, are relevant for identifying susceptible subjects (HHV-8 seropositive subjects), monitoring the immune levels in iatrogenic immune suppressed patients, and developing new therapeutic approaches based on antiviral and immune modulators.

LEARNING OBJECTIVE

This article should enable the reader: (i) to learn about the clinical and molecular aspects of KS in order to have a multidisciplinary approach to a tumour that shows unique features; (ii) to consider the role of viral agents and immunity; and (iii) to recognize properties of an opportunistic neoplasm. The identification of the HHV-8 role in KS pathogenesis should establish a relevant tool in the clinical management of KS patients.

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.

Kaposi sarcoma after treatment of Hodgkin's disease in a young adult non-AIDS patient: case report and review

We describe a young woman diagnosed with Hodgkin's disease, stage I, at age 20 years. She delayed treatment until age 23, at which time she was considered to have stage II-A disease and was then treated with chemotherapy and involved field irradiation. Two years later, Kaposi sarcoma, which developed on her right shoulder, was excised. Both the Hodgkin's disease and Kaposi sarcoma appeared to be cured, but 3 years later, acute myelogenous leukemia developed and the patient subsequently died in relapse. This is one of the very few instances of a young patient, not infected with the AIDS virus, in whom Kaposi sarcoma developed as a second malignancy after treatment of Hodgkin's disease.

Human immunodeficiency virus negative Kaposi sarcoma and lymphoproliferative disorders

BACKGROUND

The concomitant occurrence of more than one primary neoplasm in the same individual has led researchers to seek possible common etiopathogenetic factors. Kaposi sarcoma (KS) is a multicentric neoplasm of vascular origin and perhaps viral etiology. Four forms of KS are known: classic or Mediterranean, endemic or African, posttransplant, and epidemic or acquired immunodeficiency syndrome-associated KS. In its classic form KS mainly affects elderly people and often has a long and indolent course that occasionally allows other malignancies to appear. Previous studies of the possible association between human immunodeficiency virus (HIV) negative KS and lymphoproliferative disorders (LDs) have produced discordant results.

METHODS

To verify a possibly significant association between HIV negative KS and LDs, data relating to 250 evaluable Italian patients with HIV negative KS were evaluated retrospectively.

RESULTS

Of the 250 KS patients, only 6 (2.4%) were found to have had an LD: 2 with Hodgkin lymphoma, 1 with non-Hodgkin lymphoma, 1 with cutaneous T-cell lymphoma, 1 with acute promyelocytic leukemia, and 1 with B-chronic lymphocytic leukemia.

CONCLUSIONS

No significant association was found between HIV negative KS and LDs in the patient population in the current study. The authors believe that age, LD, or therapy-related immunodepression played a role in the cases in which KS appeared after the LD by determining the passing to the lytic phase of the herpes-virus HHV8 already present in anatomic sites of latency/persistence.

Classic Kaposi sarcoma: experience at Rabin Medical Center in Israel

Classic Kaposi sarcoma is an indolent cutaneous proliferative disease affecting mainly elderly people of Mediterranean and Jewish origin. The authors review the epidemiologic and clinical findings in Israeli patients with classic Kaposi sarcoma treated at the Institute of Oncology, Rabin Medical Center. A total of 123 patients were identified. The average age at diagnosis was 68 years (range, 20-90 years) and, as expected, there was a strong predominance of men (2.4:1). All but two patients were Jewish. The distribution of Ashkenazic Jews and Sephardic Jews was almost equal. Twenty-three patients (19%) had secondary malignancies that were mostly solid tumors. The clinical course was indolent and rarely fatal (4% disease-related mortality). Multivariate analysis revealed that non-Ashkenazic origin, age over 70 years, multiple lesions (>10), and immunocompromised conditions adversely affected survival. Radiotherapy for localized skin lesions yielded an 88% objective response, with symptomatic relief in 95% of patients. Chemotherapy was similarly effective (76% response rate) in patients with disseminated disease. These data demonstrate the indolent nature of classic Kaposi sarcoma which usually requires a less aggressive therapeutic approach than in the African and AIDS-related types of Kaposi sarcoma.

Kaposi's sarcoma masquerading as pyogenic granuloma of the nasal mucosa

Kaposi's sarcoma (KS) is a neoplastic vascular disorder characterized by multiple reddish blue nodules which, according to the original description (Kaposi, 1872), usually present on the skin of the upper and lower extremities. It is not until the disease progresses that nodules appear on the skin of the head and neck, on mucosal membranes and as visceral lesions. However, with the large increase in the incidence of this tumour associated with the acquired immune deficiency syndrome (AIDS) epidemic, there have been increasing numbers of cases of Kaposi's sarcoma presenting primarily on the skin or mucosa of the head and neck. The most common sites reported are within the oral cavity, particularly on the palate. Other mucosal sites are rare. We present an unusual case where the primary manifestation of the Kaposi's sarcoma was in the nasal mucosa and stress the importance of this diagnosis not being overlooked.

Kaposi's sarcoma in retrospect

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Lymphangioma-like variant of Kaposi's sarcoma: clinicopathologic study of seven cases with review of the literature

The clinical and pathological features of seven cases of lymphangioma-like Kaposi's sarcoma (KS) are reported. As with the other subtypes of KS, the lymphangioma-like variant occurs more often in men aged 59-80 years. Clinically, the lesion appears intermingled with the classical forms of KS, but a "bulla-like" appearance recognized in seven of 13 cases has been considered as a clinical hallmark of this variant. Although occasional cases have shown aggressive behavior, the most frequent clinical course is slowly progressive with localized or diffuse involvement of lower limbs. The histological pattern, characterized by permeation of dermal collagen by labyrinthine vascular channels lined by a flattened endothelium, must be differentiated from spindle cell hemangioendothelioma, low-grade angiosarcoma, targetoid hemosiderotic hemangioma, and benign lymphangioendothelioma.

Mediterranean Kaposi's sarcoma in the elderly. A randomized study of oral etoposide versus vinblastine

BACKGROUND

This Phase III trial was performed to compare the roles of oral etoposide and intravenous (i.v.) vinblastine in the treatment of Mediterranean Kaposi's Sarcoma (MEKS) in elderly patients with severe disease (Stages II, Ac/B, III, and IV).

PATIENTS AND METHODS

Sixty-five patients were randomized to receive either oral etoposide (60 mg/m2 on Days 1-3 during the first course; 60 mg/m2 on Days 1-4 during the second course, and 60 mg/m2 on Days 1-4 during the second course, and 60 mg/m2 on Days 1-5 during the third course; the courses were recycled every 3 weeks) or an i.v. bolus of vinblastine (3 mg/m2 weekly for 3 weeks, and then 6 mg/m2 every 3 weeks).

RESULTS

No significant difference between the two drugs was observed in terms of response rates (etoposide, 73.5% vs. vinblastine, 58%; P = 0.3), duration of response, or survival (median not yet reached at a median follow-up of 38 months). Side effects of both treatments were limited, although myelotoxicity was more evident in the vinblastine arm.

CONCLUSIONS

Although it is feasible and well tolerated, the oral administration of etoposide at these doses and in this regimen does not appear superior to vinblastine in the treatment of MEKS. Further evaluation of a more intensive schedule in large cooperative clinical trials is needed to establish the role of this drug in comparison with reference treatments.

Classical disseminated Kaposi's sarcoma in HIV-negative patients; an unusually indolent subtype

Kaposi's sarcoma is a rare neoplasm of characteristic chronicity. The classical form which occurs most often in elderly men of Eastern European origin, comprises both an indolent, cutaneous type marked by spontaneous regression with prolonged survival, and a rarer, disseminated variant is more fulminant. Seven elderly Jewish patients with classical, disseminated, visceral Kaposi's sarcoma were studied; they were neither homosexual nor drug-abusers. All immunologic parameters were normal and serum tests for HIV antibodies, CMV, and EBV were negative. Five of these patients were treated and four responded well, including two complete remissions. The prolonged survival of these patients (82% at 5 years) suggests the existence of an indolent subtype or forme fruste of the usually aggressive form of classical Kaposi's sarcoma.

Kaposi's sarcoma. Epidemiology, pathogenesis, histology, clinical spectrum, staging criteria and therapy

The acquired immunodeficiency syndrome (AIDS) epidemic has had a profound impact on our understanding of Kaposi's sarcoma (KS). Epidemiologic features suggest a sexually transmitted cofactor in the pathogenesis of AIDS-associated KS (AIDS-KS), and several putative agents have received intense scrutiny. Cell culture studies suggest that the angiogenesis of AIDS-KS is stimulated by both human immunodeficiency virus proteins and growth factors that may be involved in the development and progression of AIDS-KS, thereby providing a rationale for new therapeutic interventions. The dermatologist is uniquely qualified to provide care for the majority of patients with KS, as many patients have cutaneous lesions amendable to local therapy (cryotherapy, intralesional therapy, simple excision). Patients requiring more aggressive local therapy (radiation therapy) or systemic therapies (interferon, chemotherapy) can be easily recognized. Standardized staging criteria provide assistance for determining appropriate local or systemic therapy and for evaluating and comparing responses to new therapies. This article reviews the epidemiology, pathogenesis, histologic features, clinical spectrum, staging criteria, and treatment of KS.