Kaposi Sarcoma

Essentials of Diagnosis

• Human herpes virus 8 (HHV-8) or Kaposi sarcoma–associated herpes virus (KSHV), is cause of all forms of Kaposi sarcoma

General Considerations

• Classic Kaposi sarcoma

  • Occurs in older men

  • Has a chronic clinical course

  • Rarely fatal

• Endemic Kaposi sarcoma occurs in an often aggressive form in young black men of equatorial Africa

• Iatrogenic Kaposi sarcoma

  • Occurs in patients receiving immunosuppressive therapy

  • Improves upon decreasing immunosuppression

• HIV-related Kaposi sarcoma

  • Prevalence has been reduced due to antiretroviral therapy

  • However, continues to occur in both well controlled HIV infection or AIDS

Symptoms and Signs

• Red, purple, or dark plaques or nodules on cutaneous or mucosal surfaces

• Marked edema may occur with few or no skin lesions

• Commonly involves the gastrointestinal tract, but in asymptomatic patients these lesions are not sought or treated

• Pulmonary Kaposi sarcoma

  • Can present with shortness of breath, cough, hemoptysis, or chest pain

  • May be asymptomatic, appearing only on chest radiograph

• Chronic Kaposi sarcoma

  • Can develop in patients with HIV infection, high CD4 counts, and low viral loads

  • Usually resembles the endemic form, being indolent and localized

  • However, it can be clinically aggressive

Differential Diagnosis

• Bacillary angiomatosis

• Hemangioma

• Vasculitis (palpable purpura)

• Dermatofibroma

• Pyogenic granuloma

• Prurigo nodularis

• Melanoma

Laboratory Tests

• Based on appearance of skin lesions with confirmatory biopsy

Imaging Studies

• Chest radiography

Diagnostic Procedures

• Fecal occult blood testing in patients with gastrointestinal symptoms

• Bronchoscopy in patients with pulmonary symptoms

Medications

• Kaposi sarcoma in the elderly

  • Palliative local therapy with intralesional chemotherapy or radiation is usually all that is required

• In the setting of iatrogenic immunosuppression

  • The treatment is primarily reduction of doses of immunosuppressive medications

• AIDS-associated Kaposi

  • The patient should first be given effective anti-HIV antiretrovirals because in most cases this treatment alone is associated with improvement (see HIV Infection)

• Other therapeutic options include cryotherapy or intralesional vinblastine (0.1–0.5 mg/mL) for cosmetically objectionable lesions

• Systemic chemotherapy

  • Indicated for rapidly progressive skin disease (more than 10 new lesions per month), with edema or pain, and with symptomatic visceral disease or pulmonary disease

  • Liposomal doxorubicin

    • Highly effective in severe cases

    • May be used alone or in combination with bleomycin and vincristine

  • Other therapeutic options include

    • Paclitaxel

    • Etoposide

    • Bortezemib

    • Lenalidomide

  • Targeted immunotherapy with PD-1/PDL-1 blockade (nivolumab, pembrolizumab) has been successful in small series

Surgery

• Laser surgery for certain intraoral and pharyngeal lesions

Therapeutic Procedures

• Radiation therapy for accessible and space-occupying lesions

Prognosis

• Kaposi sarcoma may complicate immunosuppressive therapy, and stopping the immunosuppression may result in improvement

When to Refer

• If there is a question about the diagnosis, if recommended therapy is ineffective, or if specialized treatment is necessary

When to Admit

• Respiratory insufficiency or other signs of systemic failure