Classic Kaposi sarcoma. Which KSHV-seropositive individuals are at risk?

Prognostic analysis of cutaneous Kaposi sarcoma based on a competing risk model

The data regarding the prognosis of cutaneous Kaposi sarcoma (KS) was limited. The current study aimed to explore the risk factors and develop a predictive model for the prognosis of cutaneous KS patients. Data were extracted from Surveillance, Epidemiology, and End Results database from 2000 to 2018 and randomly divided into training and validation cohort. The Kaplan-Meier analysis, cumulative incidence function based on the competing risk model and Fine-Gray multivariable regression model was used to identify the prognostic factors and then construct a 5-, 10-, and 15-year KS-specific death (KSSD) nomogram for patients. The concordance index (C-index), area under the curve (AUC) of operating characteristics and calibration plots were used to evaluate the performance of the model. The clinical utility of the model was measured by decision curve analysis (DCA). In 2257 cutaneous KS patients identified from database, the overall median survival time was about 13 years. Radiotherapy (p = 0.013) and surgery (p < 0.001) could lower the KSSD, while chemotherapy (p = 0.042) and surgery (p < 0.001) could increase the overall survival (OS) of patients with metastatic and localized lesions, respectively. Race, number of lesions, surgery, extent of disease, year of diagnosis and age were identified as risk factors associated with cutaneous KS-specific survival. Performance of the nomogram was validated by calibration and discrimination, with C-index values of 0.709 and AUC for 5-, 10-, and 15-year-KSSD of 0.739, 0.728 and 0.725 respectively. DCA indicated that the nomogram had good net benefits in clinical scenarios. Using a competing-risk model, this study firstly identified the prognostic factors, and constructed a validated nomogram to provide individualized assessment and reliable prognostic prediction for cutaneous KS patients.

Lifestyle factors associated with sex differences in Kaposi sarcoma incidence among adult black South Africans: A case-control study

Kaposi Sarcoma (KS) is endemic in several countries in Southern and Eastern Africa, relatively rare worldwide but a leading cancer among people living with HIV. KS has always been more common in adult males than females. We assessed the prevalence of known cancer modifying factors (parity, hormonal contraceptive use in females, sex-partners, smoking and alcohol consumption in both sexes), and their relationship to KS, and whether any of these could account for the unequal KS sex ratios. We calculated logistic regression case-control adjusted odds ratios (OR_adj), and 95% confidence intervals (95%CI), between KS and each of the modifying factors, using appropriate comparison controls. Controls were cancer types that had no known relationship to exposures of interest (infection or alcohol or smoking or contraceptive use). The majority of the 1275 KS cases were HIV positive (97%), vs. 15.7% in 10,309 controls. The risk of KS among those with HIV was high in males (OR_adj=116.70;95%CI=71.35-190.88) and females (OR_adj=93.91;95%CI=54.22-162.40). Among controls, the prevalence of smoking and alcohol consumption was five and three times higher in males vs. females. We found a positive association between KS and heavy vs. non-drinking (OR_adj=1.31;95%CI=1.03-1.67), and in current heavy vs. never smokers (OR_adj=1.82;95%CI=1.07-3.10). These associations remained positive for alcohol consumption (but with wider CIs) after stratification by sex, and restriction to HIV positive participants. We found no evidence of interactions of smoking and alcohol by sex. Smoking and alcohol consumption may provide a possible explanation for the KS sex differences, given both exposures are more common in men, but confounding and bias cannot be fully ruled out. The role smoking and alcohol play in relation to viral loads of HIV/KSHV, differences in immunological responses or other genetic differences between males and females warrant further studies.

Safety and effectiveness of gemcitabine for the treatment of classic Kaposi’s sarcoma without visceral involvement

Background:

Classic Kaposi’s sarcoma (CKS) is a rare, multifocal, endothelial cell neoplasm that typically occurs in elderly people with previous infection by human herpes virus-8. Prospective trials are rare, and the choice of drugs relies on prospective trials performed on HIV-associated Kaposi’s sarcoma (KS). Pegylated liposomal anthracyclines and taxanes are considered the standard first- and second-line chemotherapy, respectively. Despite the indolent biologic behavior, the natural history is characterized by recurrent disease. This condition of chronic administration of cytotoxic drugs is often associated with immediate/long-term adverse events.

Methods:

This was an observational, retrospective study to evaluate the effectiveness and safety of gemcitabine in patients with CKS. From January 2016 to September 2021, the patients were treated with gemcitabine 1000 mg/m2 on days 1 and 8, with cycles repeated every 21 days. The treatment was administered as first or second line.

Results:

Twenty-seven (27) patients were included in the study. Twenty-one (21) out 27 patients (77.8%) achieved a partial response (PR), including 8 patients with major response (MR) (29.6%) and 13 patients with minor response (mR) (48.2%); 2 (7.4%) showed a complete response (CR), 3 (11.1%) a stable disease (SD), and 1 (3.7%) a progressive disease (PD). Tumor responses were generally rapid, with a median time to first response of 4 weeks (range, 3–12 weeks). Patients who responded had disease improvement with flattening of the skin lesions, decrease in the number of lesions, and substantial reduction in tumor-associated complications. Median duration of response was 19.2 months. Common adverse events were grades 1/2 thrombocytopenia, and grade 1 noninfectious fever. No patient discontinued treatment as a result of adverse events.

Conclusion:

Our study showed that gemcitabine is effective and well tolerated, acts rapidly on cutaneous lesions, and allows substantial symptom palliation, without dose-limiting toxicity. Gemcitabine represents a safe and effective option for the treatment of CKS.

A high seroprevalence of human herpesvirus type 8 already present in patients with chronic hepatitis before the development of cirrhosis

A high seroprevalence of human herpesvirus type 8 (HHV-8) in mild cirrhotics is significantly associated with hepatitis activity. Cirrhosis is always derived from chronic hepatitis. We aimed to evaluate the prevalence of HHV-8 infection in patients with chronic hepatitis. Blood samples collected from 129 patients with chronic hepatitis and 129 age- and sex-matched healthy controls were analysed for monocyte and platelet counts, hepatitis B surface antigen (HBsAg), anti-hepatitis C virus (anti-HCV), HHV-8 antibody and DNA, and alanine aminotransferase (ALT). Mean monocyte and platelet counts were significantly higher and lower in patients than in healthy controls (p = 0.02 and < 0.0001, respectively). Seropositive rate for HHV-8 antibodies was significantly greater in patients (32.6%) than in controls (20.9%, p = 0.04), particularly in patients with HCV infection, or higher plasma ALT levels, or both (p = 0.004, 0.01, and 0.0009, respectively). Antibody titres for HHV-8 in patients also exceeded those in controls (p = 0.02). The mean age of HHV-8 seropositive patients (60.3 years) was significantly older than that of seronegatives (52.3 years) (p = 0.0007). Patients aged 55 or older had higher seropositive rate and titres for HHV-8 antibodies than those younger (p = 0.005 and 0.007, respectively). A significantly high HHV-8 seroprevalence is already present in patients with chronic hepatitis before the development of cirrhosis, particularly in patients with HCV infection and/or higher plasma ALT levels. Advancing age seems to play an important role in HHV-8 seroprevalence in patients with chronic hepatitis.

Kaposi sarcoma incidence in females is nearly four-fold higher in the Lower Rio Grande Valley compared to the Texas average

The Lower Rio Grande Valley (LRGV) is located on U.S.-Mexican border with a population that is 90% Hispanic [1]. Comprised of Hidalgo, Cameron, Starr and Willacy counties, this region has the highest poverty rate and one of the highest incidences of Type 2 diabetes in the United States [2-4]. Previous studies demonstrated a high prevalence of Human Herpes Virus 8 (HHV8) in the LRGV [5-7]. HHV8 infection has been causally linked to Kaposi Sarcoma (KS) [8]. Here, we retrospectively examine the incidence of KS in the LRGV in a set of HIV-negative Hispanic patients. Strikingly, the incidence of KS was higher in LRGV women compared to the Texas state average (nearly four-fold higher in McAllen-Edinburg-Pharr Metro Statistical Area). This unique profile aligns with the increased HHV8 prevalence in the LRGV, suggesting that HHV8 contributes to a high incidence of HIV-negative KS on the U.S.-Mexican border in Texas.

Diabetes and risk of Kaposi's sarcoma: effects of high glucose on reactivation and infection of Kaposi's sarcoma-associated herpesvirus

Patients with diabetes are generally prone to pathogen infection and tumor progression. Here, we investigated the potential association between diabetes and Kaposi's sarcoma (KS), a tumor linked to infection with Kaposi's sarcoma-associated herpesvirus (KSHV). By using Taiwan's National Health Insurance Research Database, we found that diabetes is statistically associated with increased risk of KS in a case-control study. Since a high level of blood sugar is the hallmark of diabetes, we determined whether high glucose promotes both KSHV reactivation and infection, which are crucial for KS pathogenesis. Our results showed that high glucose significantly increases lytic reactivation of KSHV but not Epstein-Barr virus, another related human oncogenic gammaherpesvirus, in latently infected cells. Activation of the transcription factor AP1 by high glucose is critically required for the onset of KSHV lytic reactivation. We also demonstrated that high glucose enhances susceptibility of various target cells to KSHV infection. Particularly, in endothelial and epithelial cells, levels of specific cellular receptors for KSHV entry, including integrin α3β1 and xCT/CD98, are elevated under high glucose conditions, which correlate with the enhanced cell susceptibility to infection. Taken together, our studies implicate that the high-glucose microenvironment may be an important predisposing factor for KS development.

Predictors of seropositivity for human herpesvirus type 8 in patients with mild cirrhosis

The high seroprevalence of human herpesvirus type 8 (HHV-8) in moderate or severe cirrhotics appears to be associated with male sex, hepatitis B virus (HBV) infection, alcoholism, and disease severity. The status of HHV-8 infection in mild cirrhotics remains unclear. Plasma samples collected from 93 mild cirrhotics and 93 age- and sex-matched healthy controls were analyzed for HHV-8 antibody and HHV-8 DNA. Mild cirrhotics had higher seropositivity for HHV-8 antibodies than healthy controls (P=0.0001). Univariate logistic regression analysis revealed that an age ≥55 years (odds ratio (OR) 2.88, P=0.02), hepatitis C virus (HCV) infection (OR 3.42, P=0.01), and hepatitis activity (OR 4.10, P=0.004) were associated with HHV-8 seropositivity in cirrhotics. Stepwise multivariate logistic regression analysis confirmed that age ≥55 years (adjusted OR (aOR) 1.92, P=0.04) and hepatitis activity (aOR 3.55, P=0.005) were independent factors. The rate of hepatitis activity was higher in HCV-infected than in HBV-infected patients (P<0.0001) and in women than in men (P=0.0001). Cirrhotics who were seropositive for HHV-8 or HCV or had hepatitis activity were significantly older (P=0.02, <0.0001 and <0.0001, respectively). Plasma samples from all participants were negative for HHV-8 DNA. HHV-8 antibody titers in mild cirrhotics also markedly exceeded those in controls (P<0.0001), as did those in patients ≥55 years old vs. younger patients (P=0.01), those in patients with vs. without HCV infection (P=0.0008), and those in patients with vs. without hepatitis activity (P=0.0005). Mild cirrhotics had high HHV-8 seroprevalence and HCV infection, and, in particular, old age and hepatitis activity were predictors.

High prevalence of HHV8 infection and specific killer cell immunoglobulin-like receptors allotypes in Sardinian patients with type 2 diabetes mellitus

The development of type 2 diabetes is thought to involve both environmental, possibly infectious, and genetic factors. Recently, a high prevalence of human herpesvirus 8 (HHV8) infection was observed in type 2 diabetes patients, and specific killer cell immunoglobulin-like receptors (KIR) allotypes were associated to both increased susceptibility to herpesvirus infection and risk to develop diabetes. However, no clear gene-disease or virus-disease associations have been established. To investigate the possible interplay between HHV8 infection, KIR allotype and type 2 diabetes, virus prevalence and KIR genotype were analyzed by PCR in 168 patients affected by type 2 diabetes and 108 control individuals belonging to the Sardinian population. Results showed a significant increase of HHV8 prevalence in type 2 diabetes patients versus controls (57% vs. 17%, P < 0.001), and a significant increase of KIR2DL2/DS2 homozygosity in diabetes patients infected with HHV8 compared to uninfected ones (64% vs. 14%, P < 0.0001), resulting in a significant OR of 11.31. In addition, the analysis of the frequency of the KIR2DL2/DS2 receptor and its HLA-C1 ligand, accordingly to the status of HHV8 infection, showed a significant increased correlation between KIR2DL2/DS2, type 2 diabetes and HLA-C1C1 genotype in the type 2 diabetes patients infected with HHV8 compared to uninfected ones (62% vs. 15%, P < 0.0001, OR = 8.64). These findings provide preliminary evidence that HHV8 infection might be a cofactor for type 2 diabetes in a specific subset of genetically susceptible individuals, and suggest the possibility that such patients might have an impaired immune-mediated component contributing to the development of type 2 diabetes.

Cause-specific mortality in classic Kaposi's sarcoma: a population-based study in Italy (1995-2002)

Background:

Little information is available on the causes of death among persons with classic Kaposi's sarcoma (CKS).

Methods:

We conducted a population-based study in Italy to identify deceased persons with CKS and the underlying causes of death among them, by reviewing multiple-causes-of-death records. Standardised mortality ratios (SMRs) and 95% confidence intervals were calculated to compare the distribution of causes to that among the same-age general population of deceased persons. The geographical distribution was also evaluated.

Results:

Of the 946 deaths among persons with CKS, 65.9% were attributable to non-neoplastic conditions and 21.9% to malignancies. For 12.2%, no lethal pathology was identified and CKS was considered as the underlying cause. In 90% of these cases, there was visceral/nodal involvement, therapy-related complications, or neoplastic cachexia. Among persons with CKS who died of other causes, an excess for lymphoid malignancies emerged (SMR=4.40) (chronic lymphocytic leukaemia (11.03), non-Hodgkin's lymphoma (4.22), Hodgkin's lymphoma (11.80), and multiple myeloma (2.3)), balanced by a deficit for all solid cancers (0.56), with a marked deficit for lung cancer (0.41). We found an excess for respiratory diseases (chronic obstructive pulmonary disease (1.86)) and genitourinary diseases (chronic renal failure (6.47)). There was marked geographical heterogeneity in the distribution of deaths.

Conclusions:

Though referring specifically to Italy, the results are informative for other countries and populations and all cases of CKS in general.

Targeted therapy for Kaposi sarcoma

Kaposi sarcoma (KS) occurs as a result of Kaposi sarcoma-associated herpesvirus (KSHV) infection, typically in the context of one of several immunodeficient states. In the US, patients with KS may either be co-infected with HIV or receiving immunosuppressant therapy following solid-organ transplantation. Systemic treatment of KS has traditionally involved one of several chemotherapeutic agents administered either in combination or as single agents, which typically provide reasonable response rates and short-term control. However, recurrence of KS is common, and progression-free intervals are under 1 year. For these reasons, new therapies have been sought and with the elucidation of novel pathogenic mechanisms of KS infection, rational therapeutic targets have been identified. These include KSHV replication, restoration of immune competence, and signal transduction pathways utilized by KSHV in the propagation of KS. This review focuses on these emerging targets in the treatment of patients with KS and also highlights important clinicopathologic characteristics.

Risk factors for classical Kaposi sarcoma in a population-based case-control study in Sicily

BACKGROUND

Classical Kaposi sarcoma is a rare complication of Kaposi sarcoma-associated herpes virus (KSHV) infection. We conducted a population-based, frequency-matched case-control study in Sicily to further investigate the reported inverse relationship between smoking and classical Kaposi sarcoma and to identify other factors associated with altered risk.

METHODS

All incident, histologically confirmed classical Kaposi sarcoma cases in Sicily were eligible. A two-stage cluster sample design was applied to select population controls. KSHV seropositivity was determined using four antibody assays (K8.1 and orf73 enzyme immunoassays and two immunofluorenscence assays). Using SAS-callable SUDAAN, we compared the characteristics of classical Kaposi sarcoma cases and KSHV-seropositive controls. Odds ratios (OR) and 95% confidence intervals (CI) are presented.

RESULTS

In total, 142 classical Kaposi sarcoma cases and 123 KSHV-seropositive controls were recruited. Current cigarette smoking was associated with reduced risk of classical Kaposi sarcoma amongst males (OR, 0.20; 95% CI, 0.06-0.67). Edema was associated with classical Kaposi sarcoma, but only when it presented on the lower extremities (OR, 3.65; 95% CI, 1.62-8.23). Irrespective of presentation site, diabetes and oral corticosteroid medications were associated with increased risk (OR, 4.73; 95% CI, 2.02-11.1 and OR, 2.34; 95% CI, 1.23-4.45, respectively). Never smoking, diabetes, and oral corticosteroid medication use were all independently associated with classical Kaposi sarcoma risk.

DISCUSSION

We confirmed previous reports that cigarette smoking was associated with a reduced risk of classical Kaposi sarcoma, and we found that risk was lowest among current smokers. We also found that classical Kaposi sarcoma risk was strongly and independently associated with oral corticosteroid use and diabetes. Corroboration of these observations and investigation of possible underlying mechanisms are warranted.

Recombinant ORF66 and ORFK12 antigens for the detection of human herpesvirus 8 antibodies in HIV-positive and -negative patients

Human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma (KS)-associated herpesvirus (KSHV), is not routinely isolated in cell cultures, and thus detection of HHV-8-specific antibodies is usually performed. In this study, we performed recombinant antigens ORF66- and ORFK12-based Western blot strip assays and ELISA, and surveyed the seroprevalence of HHV-8 antibodies in HIV-positive and -negative patients. In serum samples from patients with positive plasma HHV-8 DNA, the sensitivity of the Western blot strip assay was 100% for the anti-ORF66 antibodies and 83.3% for the anti-ORFK12 antibodies. In addition, ORF66-based ELISA showed higher levels of specificity (87.3%) and sensitivity (84.8%) than ORFK12-based ELISA. Moreover, the area under the receiver-operating characteristics curves (AUROC) was 0.76 for ORF66-based ELISA and 0.66 for ORFK12-based ELISA. The seroprevalence of HHV-8 antibodies to ORF66 and/or ORFK12 in the HIV-infected patients (55%, 97/176) was significantly higher than in the DM patients (45%, 135/301) (P = 0.03) and the HIV-/DM-negative group (11%, 11/100) (P < 0.01). In the HIV-infected patients, the seropositivity of the HHV-8-specific antibody was 30% to both antigens, 19% to ORFK12 and 5.7% to ORF66. Importantly, HHV-8 seropositivity in the HIV-infected patients was significantly associated with the transmission method of intravenous injection and high levels of HIV RNA loading (P < 0.01), but not with gender, CD4 cell numbers or AIDS symptoms. This study assessed the sensitivity and specificity of ORF66 and ORFK12 for the detection of HHV-8 antibodies, providing novel antigens for the diagnosis of HHV-8 infection and epidemiology of HHV-8 seroprevalence.

Antibodies against Kaposi sarcoma-associated herpes virus (KSHV) complement control protein (KCP) in infected individuals

Kaposi sarcoma-associated herpesvirus (KSHV) is the most important etiopathological factor of Kaposi's sarcoma (KS) and some specific types of malignant lymphomas. One of the viral lytic genes encodes the KSHV complement control protein (KCP), which functionally mimics human complement inhibitors. Although this protein provides an advantage for evading the complement attack, it can serve as target for adaptive immune response. Herein, we identified anti-KCP IgG antibodies in patients with KS and KSHV-related lymphomas. KCP-specific antibodies were only detected in sera of those patients who had high titres of antibodies against lytic or latent KSHV antigens. Complement control protein domain 2 (CCP2) was found to be the most immunogenic part of the KCP protein. Furthermore, pre-incubation of KCP-expressing CHO cells with patient sera containing anti-KCP antibodies resulted in an increased complement deposition when incubated with human serum.