Treatment of Kaposi sarcoma in human immunodeficiency virus-1-infected Mozambican children with antiretroviral drugs and chemotherapy

Divergent clinical presentations and outcomes among children and adolescents with Kaposi sarcoma in Malawi and Tanzania

OBJECTIVES

The Kaposi sarcoma (KS) T0 versus T1 staging classification does not address the unique clinical features of paediatric KS in human gammaherpesvirus 8 (HHV-8) endemic regions of Africa. This study seeks to define patterns of childhood KS using a paediatric-specific approach.

METHODS

The Lilongwe paediatric KS staging classification categorizes disease based on clinical phenotype: stage 1 = mild/moderate KS limited to cutaneous/oral involvement, stage 2 = primarily lymphadenopathic disease, stage 3 = woody edema KS, stage 4 = visceral and/or severe/disseminated mucocutaneous disease. Characteristics and outcomes were evaluated from paediatric referral centres in Lilongwe, Malawi, and Mbeya, Tanzania.

RESULTS

Among 171 patients, the median age was 9.3 years, 37% (n = 63) were female, and 87% (n = 149) had HIV. Breakdown by stage was as follows: 18% (n = 31) stage 1, 33% (n = 56) stage 2, 19% (n = 33) stage 3, and 30% (n = 51) stage 4. Age (younger stage 2 and older stage 3), severe CD4 count suppression (lower CD4 for stages 1 and 4), and presence of severe anaemia and thrombocytopenia (worse for stages 2 and 4) differed across stages. Estimated 2-year event-free survival/progression-free survival/overall survival by stage was as follows: stage 1, 81%/81%/87%; stage 2, 50%/50%/63%; stage 3, 24%/49%/81%; and stage 4, 29%/34%/54%. Sub-analysis of stage 2 lymphadenopathic KS demonstrated superior long-term 6-year event-free survival of 70% (95% confidence interval [CI] 49-83) for younger children (aged <7 years) versus 27% (95% CI 8-51) for older children.

CONCLUSIONS

This paediatric-specific staging classification categorizes patients with distinct characteristics and patterns of treatment response. This platform may guide clinicians to provide risk-stratified treatment with the hope of improving survival among children with KS.

Endemic Kaposi's Sarcoma

Kaposi's sarcoma (KS) is a common neoplasm in Eastern and central Africa reflecting the spread of human gammaherpesvirus-8 (HHV-8), now considered a necessary causal agent for the development of KS. The endemic KS subtype can follow an aggressive clinical course with ulcerative skin lesions with soft tissue invasion or even bone or visceral involvement. In the latter cases, a thorough imaging work-up and better follow-up schedules are warranted. As KS is a chronic disease, the therapeutic goal is to obtain sustainable remission in cutaneous and visceral lesions and a good quality of life. Watchful monitoring may be sufficient in localized cutaneous forms. Potential therapeutic modalities for symptomatic advanced KS include systemic chemotherapies, immunomodulators, immune checkpoint inhibitors, and antiangiogenic drugs.

Clinical characteristics and successful treatment outcomes of children and adolescents with Kaposi sarcoma in Southwestern Tanzania

The HIV/AIDS epidemic has driven the rise in cases of Kaposi sarcoma (KS) among children and adolescents living with HIV in countries with high Human gammaherpesvirus 8 (HHV-8) seroprevalence, such as Tanzania, where specialized oncology programs are sparse. Consequently, descriptions of successful treatment of KS in children and adolescents by general pediatricians are important. A retrospective analysis was performed of children and adolescents diagnosed with KS and treated with chemotherapy and combination antiretroviral therapy (cART) at the Baylor College of Medicine Children's Foundation Tanzania Center of Excellence - Mbeya between 2011 and 2017. Sixty-one patients were diagnosed with KS with a median age of 12.6 years (interquartile range (IQR) 9.4 - 15.5). Diagnosis was confirmed by histopathology in 36% (22/61). Among HIV positive patients (59/61), 78% (46/59) were on cART at KS diagnosis. Severe immunosuppression was present in 63% (35/56) of those with CD4 data and 44% (27/61) had SAM. Advanced-stage T1 disease was present in 64% (39/61), including 28% (17/61) with visceral/disseminated KS. Two-year estimated overall survival (OS) was 72% (95% Confidence Interval (CI): 58%-82%) and median follow up for survivors was 25.7 months (IQR 14.2-53.8). No patients were lost to follow up. Two-year OS was 63% (95% CI: 44%-77%) in patients with severe immune suppression and 60% (95% CI: 37%-76%) in patients with SAM. Among patients with visceral/disseminated KS, 53% (9/17) survived. This retrospective analysis demonstrated favorable outcomes in a complex cohort of children and adolescents with KS treated with chemotherapy by general pediatricians in Tanzania.

Use of Paclitaxel to Successfully Treat Children, Adolescents, and Young Adults with Kaposi Sarcoma in Southwestern Tanzania

Treating Kaposi sarcoma (KS) in children, adolescents, and young adults (AYA) remains a challenge in low- and middle-income countries (LMIC) where chemotherapy options and availability are limited. We describe a retrospective cohort review of pediatric patients with KS treated with paclitaxel in Mbeya, Tanzania, between 1 March 2011 and 31 December 2019. Paclitaxel was given to patients who had KS relapse, a contraindication to bleomycin, vincristine, and doxorubicin (ABV), special circumstances in which a clinician determined that paclitaxel was preferable to ABV, or experienced treatment failure, defined as persistent KS symptoms at the completion of treatment. All patients also received multidisciplinary palliative care. Seventeen patients aged 5.1–21.3 years received paclitaxel, of whom 47.1% (8/17) had treatment failure, 29.4% (5/17) received paclitaxel as initial treatment, and 23.5% (4/17) had relapsed. All HIV positive patients (16/17) were given anti-retroviral therapy (ART) and 87.5% (14/16) achieved viral load <1000 cp/mL. At censure, 82.3% (14/17) of patients were alive—71.4% (10/14) achieved complete clinical remission and 28.6% (4/14) achieved a partial response. The median follow up was 37.3 months (range 8.0–83.5, IQR 19.7–41.6), and no patients were lost to follow up. In this cohort, high rates of long-term survival and favorable outcomes were possible with paclitaxel treatment.

Navigating the heterogeneous landscape of pediatric Kaposi sarcoma

Vivid descriptions of Kaposi sarcoma (KS) occurring in children and adolescents from central and eastern Africa originated over 50 years ago. Unique clinical characteristics of pediatric KS in Africa were well described within these geographic regions that were eventually understood to be endemic for human herpesvirus-8/Kaposi sarcoma herpesvirus (HHV-8/KSHV) infection, the causative agent of KS. Having catapulted in incidence with the HIV epidemic, KS is currently among the top five most common childhood cancers in numerous countries throughout the region. The main feature that differentiates the childhood form of KS from adult disease is clinical presentation with primarily bulging lymphadenopathy. This group of patients represents the most common clinical subtype of pediatric KS in KSHV-endemic regions. Lymphadenopathic KS in children is associated with other distinct features, such as sparse occurrence of prototypical hyperpigmented cutaneous lesions, frequent presentation with severe cytopenias and a normal CD4 count, and a fulminant clinical course if untreated with chemotherapy. Increased awareness and improved recognition of lymphadenopathic KS are critically important, particularly because this subset of patients typically experiences a favorable response to chemotherapy characterized by durable complete remission. Clinical phenotypes typically observed in adult KS also occur in children-mild/moderate disease limited to cutaneous and oral involvement, woody edema, and visceral disease. This review summarizes the heterogeneous patterns of disease presentation and treatment response observed among the divergent clinical phenotypes of pediatric KS, highlights additional KSHV-related malignancies, and explores some of the potential biological drivers of such clinical phenomena.

Endemic Kaposi sarcoma in HIV-negative children and adolescents: an evaluation of overlapping and distinct clinical features in comparison with HIV-related disease

BACKGROUND

Endemic Kaposi sarcoma (KS) was first described in African children over fifty years ago, but has recently been overshadowed by HIV-related disease. We aimed to evaluate the similarities and differences between endemic HIV-negative and epidemic HIV-positive pediatric KS in a KS-associated herpesvirus-endemic region of Africa.

METHODS

We describe clinical characteristics of 20 HIV-negative children with endemic KS over a six-year period and compare findings with a historical control-an HIV-related pediatric KS cohort from Lilongwe, Malawi.

RESULTS

The HIV-negative endemic KS cohort was 70% male with a median age of 9.3 years. Lymph node involvement was present in 50%, hyperpigmented skin lesions in 45%, and woody edema in 40%. One patient (5%) presented with oral KS involvement and no patients presented initially with visceral KS. Significant anemia (hemoglobin < 8 g/dL) and thrombocytopenia (platelet count < 100 × 109/L) were found at time of original KS diagnosis in 45 and 40% respectively. In both HIV-negative and HIV-positive cohorts, lymphadenopathy was the most common presentation, prototypical skin lesions were often absent, severe cytopenias were a common clinical feature, and treatment outcomes were similar. Patients with endemic KS demonstrated less frequent oral involvement (5% versus 29%, P = 0.03) and a lower proportion of patients with visceral involvement (0% versus 16%, P = 0.06).

CONCLUSIONS

These data suggest clinical overlap between epidemiological variants. Treatment protocols for pediatric KS in sub-Saharan Africa should be devised to include both endemic HIV-negative and epidemic HIV-related disease to better define the clinical and biological comparison.

Pediatric Kaposi sarcoma in context of the HIV epidemic in sub-Saharan Africa: current perspectives

The global experience with pediatric Kaposi sarcoma (KS) has evolved immensely since the onset of HIV (human immunodeficiency virus). In this review, current perspectives on childhood KS are discussed in the context of the HIV epidemic in sub-Saharan Africa. Endemic (HIV-unrelated) KS was first described over 50 years ago in central and eastern Africa, regions where human herpesvirus-8, the causative agent of KS, is endemic. With the alarming rise in HIV prevalence over the past few decades, KS has become not only the most common HIV-related malignancy in Africa, but also one of the most common overall childhood cancers throughout the central, eastern, and southern regions of the continent. The unique clinical features of pediatric KS that were described in those early endemic KS reports have been re-affirmed by the contemporary experience with HIV-related KS. These characteristics include a predilection for primary lymph node involvement, significant proportions of patients lacking prototypical cutaneous lesions, and the potential for fulminant disease progression. Other clinical features that distinguish childhood KS from adult disease include disease presentation with severe cytopenias, and the common occurrence of childhood KS without severe CD4 count suppression. Distinct clinical heterogeneity in disease presentation and treatment response have been demonstrated. Long-term complete remission and event-free survival can be achieved—especially in children with lymphadenopathic KS—utilizing treatment with antiretroviral therapy plus mild–moderate chemotherapy regimens that are well tolerated, even in low-income settings. A pediatric-specific staging classification and risk-stratification platform have been retrospectively validated, and may help guide therapeutic strategies. With expansion of the HIV treatment infrastructure throughout Africa, coupled with recent developments in establishing comprehensive pediatric oncology programs, there is great potential for improving outcomes for children with KS. Increased awareness of the unique clinical nuances and collaborative evaluations of pediatric-specific treatment paradigms are required to optimize survival for children with KS.

Triple therapy of vincristine, bleomycin and etoposide for children with Kaposi sarcoma: Results of a study in Malawian children

BACKGROUND

Kaposi sarcoma (KS) is the most common paediatric cancer in human immunodeficiency virus (HIV) endemic countries of sub-Saharan Africa, but there is little research on management and outcomes.

METHODS

Children with KS at Queen Elizabeth Central Hospital, Blantyre, Malawi treated between August 2012 and March 2015 with six courses of vincristine, bleomycin and etoposide combination chemotherapy, including antiretroviral therapy (ART) if HIV infected, were studied and outcomes compared with previously reported results.

FINDINGS

Fifty-six children were included; 38 (68%) were male; and 48 (86%) were HIV positive, of whom 36 (77%) were on ART at diagnosis. Median age at diagnosis was 8 years (interquartile range [IQR] 3-12) and median follow-up was 16.9 months (IQR 3.4-36.4). Quality of life improved in 45 (80%) children; the median Lansky Score increased from 80% pre-treatment to 100% post-treatment. Eighteen (32%) children had complete response to treatment. At 12 months, overall survival was 71% (95% confidence interval [CI] 56-82) and event-free survival (event = death, loss to follow-up or relapse) was 50% (95% CI 36-63). At 1 year, the risk of loss to follow-up was 13.4%. In a previous, same-site, randomized controlled study of vincristine monotherapy, vincristine and bleomycin, or oral etoposide, oral etoposide monotherapy had the best outcome with survival at 12 month of 66% (95% CI 46-80) and event-free survival of 52% (95% CI 33-68); however, loss to follow-up was not reported.

CONCLUSION

Overall survival, event-free survival and quality of life appear to have improved with this three-agent combination chemotherapy; however larger, randomized studies are needed to determine optimal management.

Clinical Factors Associated with Long-Term Complete Remission versus Poor Response to Chemotherapy in HIV-Infected Children and Adolescents with Kaposi Sarcoma Receiving Bleomycin and Vincristine: A Retrospective Observational Study

Kaposi sarcoma (KS) is the most common HIV-associated malignancy in children and adolescents in Africa. Pediatric KS is distinct from adult disease. We evaluated the clinical characteristics associated with long-term outcomes. We performed a retrospective observational analysis of 70 HIV-infected children and adolescents with KS less than 18 years of age diagnosed between 8/2010 and 6/2013 in Lilongwe, Malawi. Local first-line treatment included bleomycin and vincristine plus nevirapine-based highly active anti-retroviral therapy (HAART). Median age was 8.6 years (range 1.7–17.9); there were 35 females (50%). Most common sites of presentation were: lymph node (74%), skin (59%), subcutaneous nodules (33%), oral (27%), woody edema (24%), and visceral (16%). Eighteen (26%) presented with lymphadenopathy only. Severe CD4 suppression occurred in 28%. At time of KS diagnosis, 49% were already on HAART. Overall, 28% presented with a platelet count < 100 x 10⁹/L and 37% with hemoglobin < 8 g/dL. The 2-year event-free (EFS) and overall survival (OS) were 46% and 58% respectively (median follow-up 29 months, range 15–50). Multivariable analysis of risk of death and failure to achieve EFS demonstrated that visceral disease (odds ratios [OR] 19.08 and 11.61, 95% CI 2.22–163.90 and 1.60–83.95 respectively) and presenting with more than 20 skin/oral lesions (OR 9.57 and 22.90, 95% CI 1.01–90.99 and 1.00–524.13 respectively) were independent risk factors for both. Woody edema was associated with failure to achieve EFS (OR 7.80, 95% CI 1.84–33.08) but not death. Univariable analysis revealed that lymph node involvement was favorable for EFS (OR 0.28, 95% CI 0.08–0.99), while T₁ TIS staging criteria, presence of cytopenias, and severe immune suppression were not associated with increased mortality. Long-term complete remission is achievable in pediatric KS, however outcomes vary according to clinical presentation. Based on clinical heterogeneity, treatment according to risk-stratification is necessary to improve overall outcomes.

Nephronophthisis: should we target cysts or fibrosis?

Ciliopathy nephronophthisis (NPHP), a common cause of end-stage renal disease (ESRD) in children and young adults, is characterized by disintegration of the tubular basement membrane accompanied by irregular thickening and attenuation, interstitial fibrosis and tubular atrophy, and occasionally cortico-medullary cyst formation. Pharmacological approaches that delay the development of ESRD could potentially extend the window of therapeutic opportunity for this group of patients, generating time to find an appropriate donor or even for new treatments to mature. In this review we provide an overview of compounds that have been tested to ameliorate kidney cysts and/or fibrosis. We also revisit paclitaxel as a potential strategy to target fibrosis in NPHP. At low dosage this chemotherapy drug shows promising results in rodent models of renal fibrosis. Possible adverse events and safety of paclitaxel treatment in pediatric patients would need to be investigated, as would the efficacy, optimum dose, and administration schedule for the treatment of renal fibrosis in NPHP patients. Paclitaxel is an approved drug for human use with known pharmacokinetics, which could potentially be used in other ciliopathies through targeting the microtubule skeleton.

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's sarcoma in children: an open randomised trial of vincristine, oral etoposide and a combination of vincristine and bleomycin

INTRODUCTION

Kaposi's sarcoma (KS) is a common childhood cancer in places where HIV is endemic and access to antiretroviral therapy (ART) is delayed. Despite this there are no randomised trials to compare and assess chemotherapeutic regimens.

METHOD

An open label, randomised trial comparing intravenous vincristine alone, vincristine and bleomycin and oral etoposide, was carried out in children with Kaposi's sarcoma in the Queen Elizabeth Central Hospital, Blantyre, Malawi. HIV infected children were given ART after 2-3 courses of chemotherapy if they were not already on treatment. Neither HIV nor widespread KS are curable and treatment is aimed at disease reduction and improved quality of life. Tumour reduction was assessed by measuring the size of sentinel KS nodules and quality of life (QoL) by using the Lansky score. Follow up was until death or for one year.

FINDINGS

92 children were enrolled of whom 46% were naïve to ART; 10 (11%) were HIV negative. Survival was not influenced by age or gender but was better in the oral etoposide and the vincristine and bleomycin groups. P=0.0045. The group receiving oral etoposide had a better quality of life. Toxicity was not significant, and any drop in haemoglobin or white cell count could have been causally related to HIV infection rather than cytotoxic therapy.

CONCLUSION

Oral etoposide is a safe, effective treatment to contain KS and improve QoL which can be achieved without many visits to the hospital and intravenous injections.

A Review of Human Herpesvirus 8, the Kaposi's Sarcoma-Associated Herpesvirus, in the Pediatric Population

Human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma (KS)-associated herpesvirus, is the etiologic agent responsible for all types of KS. Although the majority of pediatric KS cases occur in sub-Saharan Africa, a rise in pediatric transplant KS has been reported in developed countries. In addition, HHV-8 is increasingly described as an infectious cause of hemophagocytic lymphohistiocytosis in children. Transmission of HHV-8 among children is poorly understood; however, the literature strongly suggests that horizontal transmission plays a critical role. Acute infection with HHV-8 and progression to KS in children may be different than in adults, and diagnosis may be overlooked. Currently, neither adult nor pediatric treatment guidelines exist. This review provides an overview of HHV-8 disease in children as it relates to epidemic KS, transplant KS, and other disease manifestations. The current state of the literature is reviewed and knowledge gaps are identified for future exploration.

Treatment of Kaposi sarcoma in children with HIV-1 infection

BACKGROUND

Kaposi sarcoma (KS) remains the second most frequently diagnosed HIV-related malignancy (HRM) worldwide and most common HRM in sub-Saharan Africa where HIV is most prevalent and human herpesvirus 8 (HHV-8), the precipitating agent for the development of KS, is endemic. The majority of KS patients would likely benefit from systemic chemotherapy in addition to the initiation of antiretroviral therapy (ART). However, as paediatric staging and treatment criteria are not readily available, there are no uniform treatment criteria.

OBJECTIVES

To describe the efficacy and effectiveness of current treatment options for HIV-associated KS in ART-treated paediatric populations.

SEARCH METHODS

We used standard Cochrane methods to search electronic databases and conference proceedings with relevant search terms without limits to language.

SELECTION CRITERIA

Randomised controlled trials, cohort studies, and case-control studies of HIV-infected infants and children <18 years old treated with ART and diagnosed with KS.

DATA COLLECTION AND ANALYSIS

Abstracts of all studies identified by electronic or bibliographic scanning were examined independently by two authors. We initially identified 920 references and examined 15 in detail for study eligibility. Data were abstracted independently using a standardised abstraction form.

MAIN RESULTS

After initially screening 920 titles, 15 full-text articles were closely examined by two authors. We identified four cohort studies that met our inclusion criteria for data extraction, coding, and potential meta-analysis.Using the Newcastle-Ottawa Scale and Cochrane risk of bias assessments, all observational studies had cohorts that were representative of average (treated and untreated) HIV-infected children with Kaposi sarcoma. For all outcomes of interest, no study adjusted for any other potential confounders. Two of four observational studies either explicitly described complete follow up of the study participants and/or described the characteristics of the participants lost to follow up.The use of ART together with a chemotherapeutic regimen versus ART alone appears to increase the likelihood of KS remission in HIV-infected children diagnosed with KS, although data are sparse and not adequately adjusted for staging of disease and comorbidities. Additionally, though data are sparse, the use of ART together with a chemotherapeutic regimen versus chemotherapy alone in some analyses appears to increase the likelihood of KS remission and reduce the risk of death in HIV-infected children diagnosed with KS.In this analysis, we found that the quality of evidence was very low due to small sample sizes and a paucity of paediatric literature.

AUTHORS' CONCLUSIONS

Data describing the efficacy of different treatment options for pediatric KS, to include chemotherapy and ART, are sparse. However, the use of ART together with a chemotherapy regimen may be superior to the use of ART alone or of chemotherapy alone.

Clinical characteristics and outcomes of HIV-infected children diagnosed with Kaposi sarcoma in Malawi and Botswana

BACKGROUND

Kaposi sarcoma (KS) is the most common HIV-associated malignancy in sub-Saharan Africa. The presentation and outcomes of pediatric KS are not well understood.

PROCEDURE

We performed a retrospective cohort analysis of 81 HIV-infected children with KS at the Baylor Children's Clinical Centres of Excellence in Malawi and Botswana from March 2003 to October 2009.

RESULTS

Eighty-one children with KS were identified whose median age was 8.0 (inter-quartile range 5.1-11.3) years. KS lesions were presented primarily on the skin (83%), lymph nodes (52%), and oral mucosa (41%). Occasionally disease was limited to the lymph nodes only (10%). Severe immunosuppression (70%), anemia (29%), and thrombocytopenia (17%) were common laboratory findings. Highly active antiretroviral therapy (HAART) was administered to 94% of children, including 77% who received HAART plus chemotherapy. KS immune reconstitution inflammatory syndrome (IRIS) occurred in 22%. Disease status 12 months after KS diagnosis was determined for 69 children: 43% were alive and 57% had died. Severe immunosuppression was independently associated with mortality in multivariate analysis (OR = 4.3; 95% CI 1.3-14.6; P = 0.02).

CONCLUSION

KS occurs in a significant number of HIV infected children in sub-Saharan Africa. Pediatric KS is distinct from KS in adults. Lymph node involvement was a common manifestation of KS in children, and severe immunosuppression was associated with the highest mortality risk. Though overall mortality was high in children with KS, patients did achieve clinical remission in settings with limited diagnostic and therapeutic resources.

Mucosal Kaposi sarcoma, a Rare Cancer Network study

Kaposi's sarcoma (KS) most often affect the skin but occasionally affect the mucosa of different anatomic sites. The management of mucosal KS is seldom described in the literature. Data from 15 eligible patients with mucosal KS treated between 1994 and 2008 in five institutions within three countries of the Rare Cancer Network group were collected. The inclusion criteria were as follows: age >16 years, confirmed pathological diagnosis, mucosal stages I and II, and a minimum of 6 months' follow-up after treatment. Head and neck sites were the most common (66%). Eleven cases were HIV-positive. CD4 counts correlated with disease stage. Twelve patients had biopsy only while three patients underwent local resection. Radiotherapy (RT) was delivered whatever their CD4 status was. Median total radiation dose was 16.2 Gy (0–45) delivered in median 17 days (0–40) with four patients receiving no RT. Six patients underwent chemotherapy and received from 1 to 11 cycles of various regimens namely vinblastin, caelyx, bleomycine, or interferon, whatever their CD4 counts was. Five-year disease free survival were 81.6% and 75.0% in patients undergoing RT or not, respectively. Median survival was 66.9 months. Radiation-induced toxicity was at worse grade 1–2 and was manageable whatever patients' HIV status. This small series of mucosal KSs revealed that relatively low-dose RT is overall safe and efficient in HIV-positive and negative patients. Since there are distant relapses either in multicentric cutaneous or visceral forms in head and neck cases, the role of systemic treatments may be worth investigations in addition to RT of localized disease. Surgery may be used for symptomatic lesions, with caution given the risk of bleeding.