Kaposi's Sarcoma - Classification

Classification

HHV-8 is responsible for all varieties of KS. Since Moritz Kaposi first described this malignant neoplasm, the disease has been reported in five separate clinical settings, with different presentations, epidemiology, and prognoses. All of these forms are infected with KSHV and are different manifestations of the same disease but have differences in clinical aggressiveness, prognosis and treatment.

1. Classic Kaposi sarcoma; as originally described was a relatively indolent disease affecting elderly men from the Mediterranean region, or of Eastern European descent. Countries bordering the Mediterranean basin have higher rates of KSHV/HHV-8 infection than the remainder of Europe
2. Endemic KS, which has two types, African cutaneous Kaposi sarcoma and African lymphadenopathic Kaposi sarcoma was described later in young African people, mainly from sub-Saharan Africa, as a more aggressive disease that infiltrated the skin extensively, especially on the lower limbs. This, it should be noted, is not related to HIV infection. KS is prevalent worldwide.
3. Immunosuppression-associated Kaposi sarcoma had been described, but only rarely until the advent of calcineurin inhibitors (such as ciclosporines, which are inhibitors of T-cell function) for transplant patients in the 1980s, when its incidence grew rapidly. The tumor arises either when an HHV 8-infected organ is transplanted into someone who has not been exposed to the virus or when the transplant recipient already harbors pre-existing HHV 8 infection.
4. AIDS-associated Kaposi sarcoma or Epidemic KS was described during the 1980s as an aggressive disease in AIDS patients (HIV also causes a defect in T-cell immunity). It is over 300 times more common in AIDS patients than in renal transplant recipients. In this case, HHV 8 is sexually transmitted among people also at risk for sexually transmitted HIV infection.