HIV-positive patients with lung cancer have improved prognosis with HIV treatment

HIV-positive patients with non-small-cell lung cancer have a significantly better prognosis if they take HIV treatment, French researchers report in the online edition of the journal Lung Cancer. Patients who took HIV treatment had an average survival of nine months compared to little over four months for individuals who did not take anti-HIV drugs.

The life-expectancy of HIV-positive patients has improved dramatically since effective HIV treatment became available. However, several studies have shown that non-HIV-related cancers are an increasingly important cause of illness and death in people with HIV.

Earlier research has shown that lung cancer is more common in people with HIV than in the general population. The proportion of people with HIV who smoke is higher than that seen in the general population and this may provide a partial explanation. Studies have suggested that other factors may also explain the higher risk of lung cancer seen in people with HIV, for example chronic lung disease.

Few studies have looked at the prognosis of HIV-positive patients with non-small-cell lung cancer, the most common type of lung cancer.

French researchers therefore looked at the medical records and outcomes of 49 HIV-positive patients who received treatment and care for this type of lung cancer between 1996 and 2007. They gathered information on factors that could be related to prognosis, such as demographics, smoking, details of the cancer, general health and wellbeing, stage of the cancer, treatment for the cancer, CD4 cell count, viral load, and use of HIV treatment.

Most of the patients (42, 86%) were male and Caucasian (46, 94%). All were smokers, and the average duration of smoking was 29 years. The median CD4 cell count was 350 cells/mm³ and median viral load was 1000 copies/ml. HIV treatment was being taken by 36 (73%) when their cancer was diagnosed.

Cancer treatment was provided to 43 (88%) patients. The remaining twelve individuals received supportive treatment only.

A total of twelve patients underwent surgery. These patients had a median CD4 cell count of 350 cells/mm³ and six had an undetectable viral load. After surgery seven patients were assessed as having stage I (localised) or stage II (localised, but advanced) cancer. Three patients received chemotherapy after their surgery. Ten of the patients who underwent surgery died, seven because of lung cancer. The remaining two patients were still alive without relapse.

Chemotherapy was provided to 27 patients with advanced cancer (stage IV, secondary cancers had developed or the malignancy had spread throughout the body). These patients received a median of three cycles of chemotherapy, achieving a partial response or stabilisation of the disease in 40% of patients.

The patients were followed for a median of eight months (range, 1-65 months), and 42 individuals died. Lung cancer was recorded as the cause of death in 33 (80%) patients, a non-HIV-related infection in ten patients, and AIDS in one individual.

Overall survival time from diagnosis of lung cancer was a little over eight months. The survival rate at one year after diagnosis was 34%, 17% at two years and 7% after five years.

In their first set of analysis, the investigators found that the factors associated with improved survival were use of HIV treatment, being completely asymptomatic or able to get on with daily tasks, and weight loss of below 10%.

Subsequent analysis that took into account baseline characteristics found that use of HIV treatment reduced the risk of death by 60% (p = 0.027). Patients who were completely asymptomatic (p = 0.0001), or whose cancer was localised or localised and advanced (stage I and II) (p = 0.003) also had an improved prognosis compared to patients with more severe symptoms or advanced cancer.

The researchers calculated that patients who received HIV treatment had a median survival time of nine months after diagnosis of their lung cancer compared to 4.5 months for patients who did not take antiretroviral drugs.

“To our knowledge, this is the first study demonstrating that HAART [highly active antiretroviral therapy] is a good prognostic factor for survival in HIV infected patients with non-small-cell lung cancer”, write the investigators. They note that HIV treatment has been shown to improve the prognosis of HIV-positive patients diagnosed with other cancers, particularly the AIDS-defining cancers Kaposi’s sarcoma and non-Hodgkin’s lymphoma.

Researchers looking at the use of HIV treatment during therapy for other cancers have suggested that the reduced mortality seen in people taking HIV treatment is because this therapy reduces the risk of dying from HIV-related causes. The investigators of the current study do not believe, however that the improved prognosis seen amongst patients who took HIV treatment in their study was due to this factor, noting that there was only one HIV-related death.

Other investigators have suggested that HIV treatment by itself may improve survival, or that it improves the immune system’s ability to respond to the cancer.

There is a general agreement that HIV treatment and chemotherapy can be combined, despite the possible risk of some overlapping side-effects.

The investigators conclude, “for the first time, our study has demonstrated that use of HAART is a good prognostic factor for survival among HIV infected patients with non-small-cell lung cancer”. However, as continuing HIV treatment is essential when providing chemotherapy, the investigators add “it is of critical importance that specialists in infection and oncologists collaborate in making decisions on the choice of treatment associations.”