The Cancer News

Kaposi Sarcoma in 2026: A Disease Controlled in the West, Still Devastating sub-Saharan Africa

Kaposi sarcoma (KS) represents one of the starkest global disparities in cancer care. While largely controlled in high-income countries through antiretroviral therapy (ART), KS continues to drive significant mortality in sub-Saharan Africa due to limited access to treatment, infrastructure challenges, and delayed diagnosis.

Introduction: One Disease, Two Global Realities

Kaposi sarcoma (KS) occupies a strange and uncomfortable position in modern oncology. In the United States and other high-income countries, it has become, for many clinicians, a disease of historical memory — something learned about in training but rarely, if ever, encountered in practice. A generation of dermatologists has entered the workforce having seen only one or two cases, each diagnosed by biopsy rather than clinical recognition.

But globally, and especially across sub-Saharan Africa, KS is anything but a relic. It remains the second or third leading cause of cancer and a leading cause of cancer mortality across the region. Seventy-three percent of KS cases worldwide occur in sub-Saharan Africa, and approximately 80% of cases are HIV-associated. The stark divergence between what KS looks like in a well-resourced HIV clinic in New York and what it looks like in a low-income country without reliable access to antiretroviral therapy (ART) is one of the most glaring inequities in global oncology today.

This commentary examines the biology, clinical spectrum, treatment landscape, and, critically, the barriers that continue to prevent equitable care for patients with KS worldwide.

Understanding the Biology of Kaposi Sarcoma: HHV-8 and the Role of Immunosuppression

All forms of Kaposi sarcoma share a single causative agent: human herpesvirus 8 (HHV-8), also known as Kaposi Sarcoma Herpes Virus (KSHV). Just as Human Papilloma Virus is the universal cause of cervical cancer, HHV-8 is the uniform driver of KS across all its clinical variants.

What differs dramatically by geography is the seroprevalence of HHV-8; and it’s this difference that explains much of the global disparity in KS burden. In the United States, HHV-8 seroprevalence is estimated at roughly 3 - 10% in some communities. In sub-Saharan Africa, it ranges from 30 - 90%. When you layer high HHV-8 seroprevalence onto a population with limited access to ART and high rates of HIV-related immunosuppression, the result is a KS incidence that is approximately a hundredfold higher than in settings with effective HIV control.

This relationship was illustrated clearly when the AIDS epidemic reached India: despite significant HIV spread, KS rates remained relatively low — directly attributable to the lower HHV-8 seroprevalence on the subcontinent.

Clinical Spectrum: From Indolent Skin Lesions to Life-Threatening Disease

In the United States today, KS typically presents as a handful of pigmented skin lesions in a patient on effective ART. Many of these cases are indolent, require monitoring rather than immediate treatment, and often respond to ART alone. For those patients whose KS does not regress with ART alone, chemotherapy, typically in the form of liposomal doxorubicin, is used to control the disease.

The picture in low- and middle-income countries is profoundly different. Patients present late, with advanced, life-threatening disease. They develop severe lymphedema. In some cases, amputations are required. Patients with KS in these settings uniformly present with low CD4+ cell counts — indicating deeply compromised immune systems — and high HIV viral loads, both of which accelerate disease pathogenicity. The stigma associated with KS, which was visceral and damaging in the United States during the 1990s and early 2000s, remains a daily reality for patients in these regions. It drives delayed presentation, concealment, and avoidance of care.

The difference in outcomes is stark: five-year survival rates for KS in the United States are excellent, while in sub-Saharan Africa the five-year survival rate is approximately 45%.

The Transformative Power of Antiretroviral Therapy — and Its Fragile Global Availability

Antiretroviral therapy is, then, a cornerstone of KS treatment. In patients on effective ART, response rates to systemic KS therapy rise from roughly 35–70% to approximately 90%. The immunologic restoration that ART provides fundamentally changes the disease trajectory.

The importance of ART cannot be overstated, and neither can the current threat to its global availability. For years, programs such as PEPFAR (the President's Emergency Plan for AIDS Relief) and the World Health Organization (WHO) played a critical role in delivering ART in a structured, scalable fashion to low- and middle-income countries. As the United States reduces its commitment to these global health funding mechanisms, the consequences for HIV control — and by extension, KS — will be severe and far-reaching. The reemergence of AIDS at scale in sub-Saharan Africa and other high-prevalence regions is the distressing but predictable outcome of disinvestment.

ART adherence presents its own challenges in these settings. In the U.S., the standard regimen is now a single daily pill, and the advent of long-acting injectable formulations — administered monthly or every two months — has further improved adherence for patients who struggle with daily oral therapy. In sub-Saharan Africa, stigma around HIV, irregular drug supply, and logistical barriers to consistent medication access remain significant obstacles to the consistent ART coverage that could meaningfully reduce KS incidence.

Treatment Strategies and Global Access Challenges

In the United States, National Comprehensive Cancer network (NCCN) guidelines and the Infectious Disease Society of America recommendations identify liposomal doxorubicin as the preferred first-line chemotherapy for KS, alongside paclitaxel. A landmark AIDS Malignancy Consortium trial comparing the two agents found them equally effective, but liposomal doxorubicin offered a more favorable toxicity profile — no alopecia, no significant neuropathy, no mucositis. Nivolumab, pembrolizumab, and pomalidomide have received NCCN guideline inclusion and FDA approval, respectively, though they are not yet commonly deployed in resource-limited settings.

The challenge in sub-Saharan Africa is not primarily scientific: it is economic and infrastructural. Liposomal doxorubicin costs approximately $180 per cycle, a figure that is not feasible in most low-income settings. Paclitaxel and liposomal doxorubicin also require premedication (antihistamines, corticosteroids); not to mention careful administration infrastructure that many facilities in the region simply do not have.

As a result, the most used regimen in sub-Saharan Africa has historically been bleomycin and vincristine, which require no premedication and are relatively accessible. However, the AIDS Malignancy Consortium conducted a landmark trial comparing paclitaxel to these alternatives and demonstrated a dramatic benefit for paclitaxel, with greater efficacy and less toxicity. A 2022 Lancet analysis confirmed that paclitaxel is highly cost-effective in this context. Paclitaxel is now included on the WHO List of Essential Medicines for oncology.

Bridging the Gap: Global Barriers to Cancer Care Delivery

The scientific case for wider paclitaxel deployment is clear. The implementation challenge is the remaining obstacle: there are an estimated 60 oncologists in the entirety of Nigeria, and many sub-Saharan countries have far fewer. Without trained personnel, supply chain infrastructure, and a foundational cancer care system, even a cost-effective, guideline-recommended drug cannot reach patients.

Clinical Practice Insights for Oncologists

• For clinicians in high-income settings, KS is no less pertinent of a clinical issue for its relative rarity: there are populations of people living with HIV who, owing to social or economic factors, take ART only sporadically.
• On the global stage, awareness of the disease’s global burden and biology is essential — particularly for clinicians treating immigrant populations or patients with travel histories from high-prevalence regions.
• ART is non-negotiable in any HIV- associated KS management plan. Its initiation or optimization should occur in all patients regardless of disease stage.
• Systemic chemotherapy (liposomal doxorubicin or paclitaxel in the U.S.; paclitaxel as the preferred agent in resource-limited settings) is indicated for patients with KS not responding to ART and for those presenting with advanced disease.
• Emerging immunotherapy agents, including pembrolizumab and nivolumab, are now NCCN-recommended options, though their role is evolving, and toxicity management requires appropriate infrastructure.
• Advocacy matters: clinicians and institutions with global health interests should actively support funding mechanisms, including PEPFAR and WHO programs, that deliver ART and cancer care infrastructure to low- and middle-income countries.
• Implementation science is the critical next frontier: translating evidence-based treatments into scalable, cost-effective delivery systems in resource-constrained environments.

What Patients Need to Know About Kaposi Sarcoma

Kaposi sarcoma is a cancer caused by a virus called HHV-8, and in most cases, it occurs in people living with HIV. The good news is that for people with access to HIV treatment (antiretroviral therapy), KS can often be controlled or even reversed. If you are living with HIV, staying on your medication consistently is one of the most powerful things you can do to reduce your risk. If you notice unusual pigmented or raised skin lesions, swollen limbs, or other unexplained changes, speak with your doctor as soon as possible — early diagnosis makes a significant difference in outcomes. For patients in parts of the world where HIV medications are harder to access, advocacy for global health funding is a matter of life and death.

Key Takeaways on Kaposi Sarcoma Disparities

• KS is a major global health crisis: 73% of cases occur in sub-Saharan Africa, where it is the second or third leading cause of cancer and carries a five-year survival rate of only ~45%.
• HHV-8 seroprevalence — ranging from 30–90% in sub-Saharan Africa versus 3–10% in the U.S. — combined with limited ART access drives the hundredfold higher KS incidence in low-income settings.
• ART is the cornerstone of KS therapy, improving chemotherapy response rates from 35–70% to approximately 90%; threats to PEPFAR and WHO funding place this progress at serious risk.
• Paclitaxel is the recommended and cost-effective preferred chemotherapy in sub-Saharan Africa, per the AIDS Malignancy Consortium trial and a 2022 Lancet economic analysis, though implementation barriers (including workforce shortages and infrastructure gaps) remain formidable.
• The gap between high- and low-income countries in KS outcomes is not inevitable, but the product of policy, funding, and infrastructure decisions that can and must be addressed.

Frequently Asked Questions About Kaposi Sarcoma

What causes Kaposi sarcoma?

Kaposi sarcoma is caused by human herpesvirus 8 (HHV-8), particularly in individuals with weakened immune systems, such as those living with HIV.

Why is Kaposi sarcoma more common in sub-Saharan Africa?

Higher HHV-8 prevalence, limited access to ART, and healthcare infrastructure gaps contribute to significantly higher incidence and mortality rates.

Can Kaposi sarcoma be treated effectively?

Yes. With consistent antiretroviral therapy and appropriate chemotherapy, KS can often be controlled or even reversed, especially when diagnosed early.

What is the role of ART in KS treatment?

ART restores immune function and significantly improves response to cancer treatment, making it essential in managing HIV-associated KS.

What treatments are used for advanced Kaposi sarcoma?

Common treatments include liposomal doxorubicin and paclitaxel. In resource-limited settings, paclitaxel is considered cost-effective and recommended.

References and Resources

1. AIDS Malignancy Consortium. Trial comparing paclitaxel to bleomycin/vincristine in sub-Saharan Africa. (Referenced in presentation; full citation details not provided in transcript.)
2. Lancet. (2022). Cost-effectiveness analysis of paclitaxel for Kaposi sarcoma in low- and middle-income countries.
3. National Comprehensive Cancer Network (NCCN). Guidelines for Kaposi Sarcoma. Available at: nccn.org
4. Infectious Diseases Society of America. HIV-associated Kaposi Sarcoma Treatment Guidelines.
5. World Health Organization. WHO Model List of Essential Medicines — Oncology. Available at: who.int
6. PEPFAR (President's Emergency Plan for AIDS Relief). Available at: pepfar.gov

About the Author

Dr. David Aboulafia is an attending hematologist/oncologist at Virginia Mason Clinic where he has been on staff since 1990, and has served as the Section Head in the department of Hematology/Oncology. His clinical focus involves benign and malignant hematology and primary and subspecialty HIV care. He has published over 250 articles in peer-reviewed journals that have focused on the medical care of patients he sees in his clinical practice. He is a principal investigator of the National Cancer Institute-funded AIDS Malignancy Consortium and chair of the AMC outreach, education, recruitment, and retention committee. He is also a Clinical Professor of Medicine in the Division of Hematology at the University of Washington.