Diagnosis with pulmonary KS still `ominous` even in era of potent HIV therapy

Only 50% of individuals diagnosed with pulmonary Kaposi’s sarcoma (KS) are alive five years later, according to a study conducted at Europe’s largest HIV treatment centre and published in the July edition of HIV Medicine. Doctors from the Chelsea and Westminster Hospital in London also found that the median survival time for patients diagnosed with pulmonary KS was only 19 months.

Analysis also showed that African patients were significantly more likely to be diagnosed with pulmonary KS than non-Africans, mainly because this group of patients were more likely to have their HIV infection diagnosed when they already had extremely weak immune systems.

KS is an AIDS-defining cancer and it is the most common malignancy seen in HIV-positive individuals. Thanks to potent antiretroviral therapy, the incidence of KS has fallen dramatically in countries like the United Kingdom in recent years, but KS still causes a significant amount of illness and death in settings where there is limited access to antiretroviral therapy.

Before potent HIV treatment became available, approximately 6 - 32% of KS cases involved the lungs, and an earlier study at the Chelsea and Westminster Hospital showed that the median survival of patients with pulmonary KS in the era before effective HIV therapy was only four months.

Doctors at the Chelsea and Westminster Hospital wanted to see if there were any clinical and pathological differences between patients diagnosed with KS and pulmonary KS in the period since effective HIV treatment became available. They also wished to see if the overall survival of patients with pulmonary KS had improved.

A total of 305 individuals were diagnosed with KS between 1996 and 2005 and of these 25 had pulmonary KS. Evidence pointed to the diagnosis of pulmonary KS being associated with the late diagnosis of HIV. Individuals diagnosed with pulmonary KS had significantly lower CD4 cell counts at the time of diagnosis than those patients with non-pulmonary KS (32 cells/mm³ versus 128 cells/mm³, p = 0.005).

The investigators also noted that 36% of patients with pulmonary KS were of African origin against only 10% of patients with non-pulmonary KS (p = 0.001). Late diagnosis amongst Africans has been identified as a problem in the UK. What’s more the lack of use of HIV therapy, despite severe immunological damage, pointed to the late diagnosis of HIV. The investigators also found that only 20% of all patients with KS had taken three or more months of antiretroviral therapy and that only 9% had a viral load below 50 copies/ml.

KS, regardless of its site, was treated with a combination of antiretroviral therapy and chemotherapy. Overall five year survival was significantly poorer amongst patients with pulmonary KS than amongst patients with non-pulmonary KS (49% versus 82%, p

“Pulmonary KS remains an ominous diagnosis even in the years of highly active antiretroviral therapy”, conclude the investigators.