Kaposi sarcoma

Disease Description (Causes and Symptoms)

• Causes and pathophysiology
  • Kaposi's sarcoma is a malignant tumor of vascular origin associated with infection by human herpesvirus 8 (HHV-8; KSHV). When HHV-8 infects vascular (lymphatic) endothelial cells, it induces cell proliferation and angiogenesis, resulting in sarcoma. The risk of developing the disease increases greatly in states of impaired immune function (e.g., HIV/AIDS and immunosuppression after organ transplantation) (the incidence in transplant recipients is dozens to hundreds of times higher than in the general population).
  • Morphological and pathological features include multiple or clustered vascular lesions, which can involve not only the skin and mucous membranes but also internal organs such as the lymph nodes, lungs, gastrointestinal tract, and liver.
• Main symptoms
  • Skin lesions: painless red/purple/brown macules, papules, and nodules (gradually increasing in size)
  • Mucosal lesions (e.g., oral): ulcers and masses, with possible bleeding
  • With lymph node involvement: localized or extensive lymphedema (e.g., swelling of the legs or face)
  • With lung involvement: cough, shortness of breath, and wheezing — if progression is rapid, there is a risk of respiratory failure
  • With gastrointestinal involvement: initially asymptomatic → as it progresses, nausea, vomiting, abdominal pain, intestinal obstruction, hematochezia, etc.
  • Systemic symptoms: weight loss, fatigue, etc., as the disease progresses

Treatment Methods

• General principles
  • As a chronic disease that is difficult to cure, treatment aims to relieve symptoms, control the number and size of lesions, and prevent complications. In organ transplant recipients, the condition may improve when immunosuppression is reduced, and HIV-associated Kaposi's sarcoma often improves with antiretroviral therapy (ART/HAART).
• Local treatment (suitable for localized lesions)
  • Surgical removal (for a single or small lesion)
  • Laser treatment, cryotherapy (cryo), electrocautery, etc.
  • Local injection therapy (e.g., interferon in some cases)
  • Radiation therapy: effective for pain relief and local lesion control
• Systemic treatment (for extensive disease, visceral involvement, or progressive lesions)
  • Chemotherapy: liposomal doxorubicin, paclitaxel, etc.
  • Immunotherapy: interferon-α may be effective in some patients
  • HIV-positive patients: initiation or optimization of potent ART (HAART) — often induces improvement of lesions
  • Transplantation-related: if possible, consider reducing or adjusting the immunosuppressant dose (a balance with the risk of rejection is necessary)
• Other management
  • Management of lymphedema: compression therapy, physical therapy, and skin care
  • If bleeding or obstructive complications occur, symptom-specific emergency treatment (hemostasis for bleeding, surgery for intestinal obstruction, etc.)
• Precautions and risk of complications
  • Because abruptly stopping immunosuppression can cause transplant rejection, follow the doctor's instructions
  • Involvement of the lungs, airway, or gastrointestinal tract can be life-threatening, requiring early diagnosis and treatment
  • Treatment (chemotherapy, interferon, and radiation) can cause systemic side effects (bone marrow suppression, increased susceptibility to infection, etc.), so monitoring is necessary
• Key points for self-care (lifestyle management)
  • Record changes in skin lesions (size, color, bleeding, pain, etc.) along with photographs
  • Maintain skin hygiene to prevent wounds and infections
  • Manage immune status: if HIV-positive, take ART diligently; transplant recipients should follow their medication regimen
  • Limit behaviors that can impair immune function, such as smoking and excessive drinking

Checklist Before an Outpatient Visit (Including Preparation Items and Example Questions)

• Items to bring and things to check
  • A list of current medications (immunosuppressants, antiretroviral drugs, anticoagulants, etc.), including dosing times and doses
  • Previous medical records: transplant history, whether HIV has been diagnosed, CD4 count and HIV viral load (recent test results if possible)
  • Previous pathology (biopsy) results and pathology slides/reports (if available)
  • Recent imaging results (chest/abdominal CT, endoscopy, etc.)
  • Photographs of lesions (with a clock or body site shown) and a record of when symptoms began and changed
  • Other underlying diseases (liver or kidney disease, cardiovascular disease, etc.)
• Symptom checklist to record in advance for the outpatient visit
  • Whether the number and size of lesions have changed, and whether bleeding or pain is present
  • Respiratory symptoms (cough, shortness of breath) and digestive symptoms (nausea, abdominal pain, hematochezia)
  • Recent weight changes, fever, fatigue, and other systemic symptoms
• It is recommended to collect examples of photographs to show the primary doctor
• Tests that may be performed during an outpatient visit (anticipated)
  • Skin/mucosal biopsy (pathology and HHV-8 testing), chest/abdominal imaging (CT), endoscopy or bronchoscopy if necessary, blood tests (CBC, liver and kidney function), and HIV-related tests (CD4, viral load), etc.

General Example Questions to Ask the Doctor

• Has it been confirmed that this lesion is HHV-8-positive? Please show me the biopsy results.
• Is local treatment sufficient in my case, or is systemic treatment necessary?
• What standard treatment (medication/radiation/surgery) is recommended for my condition? What are the expected effects and side effects?
• If my immunosuppressants (or ART) need to be adjusted, what risks are involved (rejection, viral reactivation, etc.)?
• Please tell me the follow-up schedule and which tests I need (imaging, blood tests, etc.).

Examples of Disease-Specific Questions

• (If HIV-positive) How do my current CD4 count and viral load affect treatment decisions for Kaposi's sarcoma? Is a change or intensification of ART necessary?
• (If a transplant recipient) If reducing immunosuppressants is considered, how will the risk of rejection and the possibility of improvement in Kaposi's sarcoma be assessed? Would switching to an alternative medication (e.g., an mTOR inhibitor) be helpful?