Immunohistochemistry in Kaposi's sarcoma

Unveiling the role of KSHV-infected human mesenchymal stem cells in Kaposi's sarcoma initiation

Kaposi's sarcoma (KS) may derive from Kaposi's sarcoma herpesvirus (KSHV)-infected human mesenchymal stem cells (hMSCs) that migrate to sites characterized by inflammation and angiogenesis, promoting the initiation of KS. By analyzing the RNA sequences of KSHV-infected primary hMSCs, we have identified specific cell subpopulations, mechanisms, and conditions involved in the initial stages of KSHV-induced transformation and reprogramming of hMSCs into KS progenitor cells. Under proangiogenic environmental conditions, KSHV can reprogram hMSCs to exhibit gene expression profiles more similar to KS tumors, activating cell cycle progression, cytokine signaling pathways, endothelial differentiation, and upregulating KSHV oncogenes indicating the involvement of KSHV infection in inducing the mesenchymal-to-endothelial (MEndT) transition of hMSCs. This finding underscores the significance of this condition in facilitating KSHV-induced proliferation and reprogramming of hMSCs towards MEndT and closer to KS gene expression profiles, providing further evidence of these cell subpopulations as precursors of KS cells that thrive in a proangiogenic environment.

Kaposi's Sarcoma in Children After Hematopoietic Stem Cell Transplantation: Two Cases of Rare Primary Tumor Localizations in the Lungs and Lymph Node

Kaposi's sarcoma (KS) is a vascular / mesenchymal tumor with an indefinite degree of malignancy, caused by complex etiopathogenetic factors including Human Herpes Virus-8 infection of immunocompromised patients. For example, KS is more common in adult men with HIV. We describe 2 very rare cases of iatrogenic KS in children after hematopoietic stem cell transplant with isolated organ damage (case 1: lung; case 2: inguinal lymph node). KS is a potential complication of bone marrow transplant in pediatric patients and can occur in different age groups and at atypical sites.

Cellular angiolipoma: a case report and review of the literature

Cellular angiolipoma is a rare subtype of angiolipoma, with vascular density approaching 95%. This case report describes a 55-year-old female that presented for treatment of a mass in her left breast that had been tender to slightly painful on palpation for nearly 2 years The patient underwent surgical excision of the mass, which was pathologically confirmed as a cellular angiolipoma. As of the 3-year follow-up, the patient reported no recurrence of the lesion. It is important to report this case and refresh knowledge of this and similar lesions to raise awareness of this diagnosis and treatment and improve future management of cellular angiolipoma cases.

The Burden of Skin Cancers in Saudi Arabia Through 2011-2022

Introduction Skin cancers are classified into melanoma and non-melanoma or keratinocyte cancers. No recent data are found about the epidemiology of skin cancers in Saudi Arabia. The current study aims to determine the burden of skin cancer in the last 11 years from 2011 to 2022. Methods Patients who were diagnosed with any type of skin cancer were enrolled in the study. The diagnosis was conducted based on histopathology and immunohistochemistry. Different variables like age, type of cancer, type of lesions, and treatment approach used were measured. Results A total of 91 patients were diagnosed with skin cancers during the study period. The head and neck were the most common sites for skin cancers. Only 4/91 cases reported invasive melanoma. Both squamous cell carcinoma (SCC) (34/91) and basal cell carcinoma (BCC) (28/91) were found to be the most reported skin cancers. Other cancers including mycosis fungoides (MF) (10/91), Kaposi's sarcoma (6/91), and dermatofibrosarcoma protuberans (DFSP) (5/91) were also detected. The rest of the detected tumors were rarely detected. Aggressive CD4+/CD4+/CD8+ MF was more prevalent than CD3+/CD4+/CD8- MF cancer cases. CD34+ /S100- DFSP cancers were evident in most of the DFSP cases. Human herpes virus 8 was detected in all Kaposi's sarcoma cases and all of them were HIV-confirmed cases. Surgical treatment was the most frequently used approach to treat skin cancers, followed by phototherapy (9.9%), surgical/radiotherapy (5.5%), surgical/chemotherapy (4.4%), chemotherapy (3.3%), and then chemoradiotherapy immunotherapy (1.1%). Conclusion The incidences of SCC and BCC are relatively high in comparison to other types of skin cancers with the surgical intervention being most frequently used.

Human Herpesvirus 8 (HHV-8) Staining: A Savior in Early Kaposi Sarcoma

Kaposi sarcoma (KS) is a low-grade vascular neoplasm associated with human herpesvirus 8 (HHV-8) infection. The disease has various phases, and the morphology of the lesion may vary, especially in the early course of the disease, where the morphological features may not be even suggestive of Kaposi sarcoma. The authors take this opportunity to report a case of Kaposi sarcoma where the diagnosis was established because of HHV-8 staining rather than its histopathological features.

Disseminated Kaposi Sarcoma

AIDS-associated Kaposi sarcoma (KS) is the most common HIV-associated neoplasm. Disseminated Kaposi sarcoma became rare with the application of antiretroviral therapy. Oral AIDS-associated KS has prognostic relevance, indicating higher mortality than those with cutaneous lesions only. In this study, we reported a 40-year-old man presented with ulcerated violaceous plaques on his hard palate. Similar lesion can be observed on his left groin and anus, as well as on esophagus and gastric fundus under upper gastrointestinal endoscopy. Histological examination accorded with KS. After five cycles of doxorubicin, his oral, skin and esophagus lesions regressed considerably.

Kaposi's Sarcoma Management from a Plastic Surgery Perspective

Kaposi's Sarcoma (KS) is a low-grade angioproliferative tumor arising from endothelial cells and associated with Human Herpes Virus 8 infection. Although KS cases are not rare and there are considerable number of patients referred for surgical excision, the plastic surgery literature on KS is exceptionally scarce. Thirty patients who were operated with the diagnosis of KS between March 2015 and January 2020 were included. Preoperative HIV tests and detailed whole-body examinations of the patients were performed. As a surgical method, for lesions with sizes ranging from 0.5 * 1 cm to 2 * 3 cm, excisions were made over the deep skin fascia by placing a margin between 0.5-1 cm, considering the anatomical location and elasticity of the skin. Primary repair was performed in 40 lesions and 12 lesions of 8 patients were repaired with a skin graft. In four patients the repair was performed with local skin flaps. Higher upper extremity involvement, less systemic involvement and less pronounced male predominance have been important results in our study that we have found different from the literature data. Compared to the therapies such as radiotherapy, laser, or chemotherapy which require several administrations; one-stage surgical excision of the lesions provides remarkable advantages.

Clinicopathologic Correlation of Kaposi Sarcoma Involving the Ocular Adnexa: Immunophenotyping of Diagnostic and Therapeutic Targets

PURPOSE

To describe the clinicopathologic characteristics and the expression of diagnostic/treatment targets in ocular adnexal Kaposi Sarcoma.

METHODS

We conducted a clinical-pathologic retrospective case series. Immunohistochemical staining for cluster of differentiation 31 (CD31), human herpesvirus-8 (HHV8), platelet-derived growth factor receptor alpha (PDGFR-A), vascular endothelial growth factor receptor-1 (VEGF), tyrosine-protein kinase Kit (c-Kit), and programmed cell death protein 1 (PD-1) were performed. Percentage of positive tumor cells was recorded for PD-1; staining intensity and distribution (H-score) were determined for the remaining stains. A Friedman non-parametric ANOVA analysis evaluated the staining.

RESULTS

The study cohort included 13 patients (age 25 to 95 years; mean 46): 7 lesions were in the eyelid, 5 in the conjunctiva, and 1 in the cornea. Nine of 11 lesions (82%) were in human immunodeficiency syndrome-positive patients (human immunodeficiency syndrome status was unknown in 2 cases). Staging included 6 plaques and 7 nodules. The mean H-scores of CD31, HHV8, c-Kit, VEGF, and PDGF-A were 8.00, 8.23, 2.77, 11.54, and 10.31, respectively. Mean PD-1 staining was 6.46%. The Friedman non-parametric ANOVA analysis showed VEGF, PDGF-A, CD31, and HHV8 differed significantly, and all differed significantly from c-Kit. Programmed cell death protein 1 staining was not significant with any clinical variable.

CONCLUSIONS

Cluster of differentiation 31 and HHV8 are helpful diagnostic adjuncts for ocular adnexal Kaposi Sarcoma. Platelet-derived growth factor receptor alpha and VEGF are promising treatment targets. Programmed cell death protein 1/PD-L1 and c-Kit are targets that are useful in several tumors; their roles in ocular adnexal Kaposi Sarcoma warrant further studies.

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.

A Series of Patients with Kaposi Sarcoma (Mediterranean/Classical Type): Case Presentations and Short Update on Pathogenesis and Treatment

BACKGROUND:

Kaposi’s sarcoma was first described in 1872 by Moritz Kaposi. To date, it is considered a malignant disease is originating from the endothelial cells of the lymphatic vessels believed to be infected with HHV-8. The current classification defines four major epidemiological forms of Kaposi’s sarcoma: classical, endemic, AIDS-associated, and iatrogenic.

CASE REPORT:

A 90-year-old male is presented with multiple plaques- and tumour-shaped brown-violet formations located on an erythematous-livid base in the area of both feet and both shanks. Two samples were taken from the lesions on the skin of the shanks, with histopathological examination and the subsequent immunohistochemistry showing Kaposi’s sarcoma.

CONCLUSIONS:

Kaposi sarcoma is a disease that causes difficulties both in diagnostic and therapeutic respect. The only sure way to determine the correct diagnosis is immunohistochemical staining with the anti-HHV8 antibody. Despite the wide range of systematic and local treatment options, there is still no unified algorithm and a unified strategy for the treatment of Kaposi’s sarcoma.

Hepatic Kaposi sarcoma: A case report and review of the literature

Kaposi sarcoma (KS) is an aggressive cancer caused by human herpesvirus-8, primarily seen in immunocompromised patients. As opposed to the well-described cutaneous manifestations and pulmonary complications of KS, hepatic KS is rarely reported before death as most patients with hepatic KS do not manifest symptoms or evidence of liver injury. In patients with acquired immune deficiency syndrome, hepatic involvement of KS is present in 12%-24% of the population on incidental imaging and in approximately 35% of patients with cutaneous KS if an autopsy was completed after their death. Patients with clinically significant hepatic injury due to hepatic KS usually have an aggressive course of disease with hepatic failure often progressing to multi-organ failure and death. Here we report an unusual presentation of acute liver injury due to hepatic KS and briefly review the published literature on hepatic KS.

Variability of HHV8 LNA-1 Immunohistochemical Staining Across the 3 Histologic Stages of HIV-Associated Mucocutaneous Kaposi Sarcoma: Is There a Relationship to Patients' CD4 Counts?

The histologic diagnosis of Kaposi sarcoma (KS) can be confirmed with human herpes virus 8 (HHV8) latency-associated nuclear antigen (LNA)-1 immunohistochemistry, which may show variability in distribution and intensity. This retrospective study was aimed at addressing the factors that may contribute to this variability. All cases of mucocutaneous KS diagnosed in a 5-year period at the histopathology department at a tertiary hospital in South Africa with available patients' CD4 counts and HHV8 LNA-1 immunohistochemically stained slides were reviewed, and the biopsy stages of KS (patch/plaque/nodular), CD4 counts, immunohistochemistry staining method (manual vs. automated), and distribution (diffuse/focal) and intensity (strong/weak) of HHV8 LNA-1 staining were recorded. A total of 127 cases were reviewed. No relationship was demonstrated between the median CD4 count and the histologic stages of KS (P = 0.701) or the intensity and distribution of HHV8 immunohistochemical staining using either staining method. Multivariate analysis showed that method of immunohistochemical staining was a significant predictor of distribution (P = 0.006) and intensity (P = 0.044) of staining, and that stage was a significant predictor of distribution of staining (P = 0.033).

Kaposi Sarcoma of Childhood: Inborn or Acquired Immunodeficiency to Oncogenic HHV-8

Kaposi sarcoma (KS) is an endothelial malignancy caused by human herpes virus-8 (HHV-8) infection. The epidemic and iatrogenic forms of childhood KS result from a profound and acquired T cell deficiency. Recent studies have shown that classic KS of childhood can result from rare single-gene inborn errors of immunity, with mutations in WAS, IFNGR1, STIM1, and TNFRSF4. The pathogenesis of the endemic form of childhood KS has remained elusive. We review childhood KS pathogenesis and its relationship to inherited and acquired immunodeficiency to oncogenic HHV-8.

Kaposi sarcoma-associated herpesvirus-associated malignancies: epidemiology, pathogenesis, and advances in treatment

Kaposi sarcoma associated herpesvirus (KSHV), a γ2-herpesvirus, also known as human herpesvirus-8, is the etiologic agent of three virally associated tumors: Kaposi sarcoma, a plasmablastic form of multicentric Castleman disease (KSHV-MCD), and primary effusion lymphoma. These malignancies are predominantly seen in people with acquired immunodeficiencies, including acquired immunodeficiency syndrome and iatrogenic immunosuppression in the setting of organ transplantation, but can also develop in the elderly. Kaposi sarcoma (KS) is most frequent in regions with high KSHV seroprevalence, such as sub-Saharan Africa and some Mediterranean countries. In the era of combination antiviral therapy, inflammatory manifestations associated with KSHV-infection, including KSHV-MCD, a recently described KSHV-associated inflammatory cytokine syndrome and KS immune reconstitution syndrome also are increasingly appreciated. Our understanding of viral and immune mechanisms of oncogenesis continues to expand and lead to improved molecular diagnostics, as well as novel therapeutic strategies that employ immune modulatory agents, manipulations of the tumor microenvironment, virus-activated cytotoxic therapy, or agents that target interactions between specific virus-host cell signaling pathways. This review focuses on the epidemiology and advances in molecular and clinical research that reflects the current understanding of viral oncogenesis, clinical manifestations, and therapeutics for KSHV-associated tumors.

Viral profiling identifies multiple subtypes of Kaposi's sarcoma

Kaposi’s sarcoma (KS), caused by KS-associated herpesvirus (KSHV), is the most common cancer among HIV-infected patients in Malawi and in the United States today. In Malawi, KSHV is endemic. We conducted a cross-sectional study of patients with HIV infection and KS with no history of chemo- or antiretroviral therapy (ART). Seventy patients were enrolled. Eighty-one percent had T1 (advanced) KS. Median CD4 and HIV RNA levels were 181 cells/mm³ and 138,641 copies/ml, respectively. We had complete information and suitable plasma and biopsy samples for 66 patients. For 59/66 (89%) patients, a detectable KSHV load was found in plasma (median, 2,291 copies/ml; interquartile range [IQR], 741 to 5,623). We utilized a novel KSHV real-time quantitative PCR (qPCR) array with multiple primers per open reading frame to examine KSHV transcription. Seventeen samples exhibited only minimal levels of KSHV mRNAs, presumably due to the limited number of infected cells. For all other biopsy samples, the viral latency locus (LANA, vCyc, vFLIP, kaposin, and microRNAs [miRNAs]) was transcribed abundantly, as was K15 mRNA. We could identify two subtypes of treatment-naive KS: lesions that transcribed viral RNAs across the length of the viral genome and lesions that displayed only limited transcription restricted to the latency locus. This finding demonstrates for the first time the existence of multiple subtypes of KS lesions in HIV- and KS-treatment naive patients.

KS is the leading cancer in people infected with HIV worldwide and is causally linked to KSHV infection. Using viral transcription profiling, we have demonstrated the existence of multiple subtypes of KS lesions for the first time in HIV- and KS-treatment-naive patients. A substantial number of lesions transcribe mRNAs which encode the viral kinases and hence could be targeted by the antiviral drugs ganciclovir or AZT in addition to chemotherapy.

Immunohistochemical detection of the latent nuclear antigen-1 of the human herpesvirus type 8 to differentiate cutaneous epidemic Kaposi sarcoma and its histological simulators

Kaposi's sarcoma is the most common neoplasia diagnosed in AIDS patients and the expression of the human herpesvirus-8 (HHV-8) latent nuclear antigen-1 has been useful for its histological diagnosis. The aim of this study is to confirm that immunohistochemistry is a valuable tool for differentiating KS from its simulators in skin biopsies of HIV patients. Immunohistochemical and histological analyses were performed in 49 Kaposi's sarcoma skin biopsies and 60 of its histological simulators. Positivity was present in the 49 Kaposi's sarcoma skin biopsies and no staining was observed in the 60 simulators analyzed, resulting in sensibility and specificity of 100%. HHV-8 immunohistochemical detection is an effective tool for diagnosing Kaposi's sarcoma, especially in early lesions in which neoplastic features are not evident. It also contributes to its histological differential diagnosis.

Kaposi sarcoma

Kaposi sarcoma (KS) is a low-grade vascular tumor associated with Kaposi sarcoma herpesvirus/human herpesvirus 8 (KSHV/HHV8) infection. Kaposi sarcoma lesions predominantly present at mucocutaneous sites, but may involve all organs and anatomic locations. Recognized epidemiologic-clinical forms of KS include classic, African (endemic), AIDS-associated (epidemic), and iatrogenic KS. New clinical manifestations have been described, such as antiretroviral therapy-related KS regression or flares. Kaposi sarcoma lesions evolve from early (patch stage) macules into plaques (plaque stage) that grow into larger nodules (tumor stage). Newer histologic variants include anaplastic, hyperkeratotic, lymphangioma-like, bullous, telangiectatic, ecchymotic, keloidal, pyogenic granuloma-like, micronodular, intravascular, glomeruloid and pigmented KS, as well as KS with sarcoidlike granulomas and KS with myoid nodules. Latency-associated nuclear antigen (HHV8) is the most specific immunohistochemical marker available to help distinguish KS from its mimics. Since KS remains one of the most common AIDS-defining malignancies, it is important that pathologists be able to recognize KS and its contemporary manifestations.