The comorbidity between HIV and cancer is proven - cancer can grow by invading the host’s immune defenses and benefiting from a loss of immunological control. Thanks to treatments, people living with HIV are living longer, but HIV seems to accelerate the ageing process, with a high incidence of cancer in HIV-carrying patients.
Eric Raymond, Professor of Medical Oncology and Medical Director at SCOR Global Life, discusses the evolution of HIV and treatments with Professor Brigitte Autran, who has devoted her career to HIV infection and has recently developed research into a vaccine against the condition.
Dr Raymond (DR)
Prevention and detection remain the best ways to contain transmission and the contamination of new people. But a preventive treatment has emerged recently that could be promising for the eradication of HIV.
How do you view the new strategy for HIV prevention in Europe, and also around the world?
Pf. Autran (PFA)
Prevention has been introduced worldwide for several years now, and is based on treatment rather than on vaccines, since we don’t yet have a vaccine. The strategy of preventing HIV through treatment follows two major directions: first to treat patients who are already infected, which blocks the dissemination of the virus; and second to treat individuals who are not yet infected but who are exposed to the risk of contamination. This second strategy is again developed in 2 ways. The first consists of taking antiretroviral pills before exposure to HIV, like the preventative treatment for malaria. This is incredibly efficient, with 97 to 98% efficacy, but it is a tough strategy, imposing strict respect of the treatment for uninfected individual patients – they have to take their pills every day. The second strategy, which also involves treating uninfected individuals, consists of treating after exposure. But again, it’s not easy because the individuals have to take the pill within 4 to 48 hours after exposure.
Given the difficulties for the individual in terms of either taking the pill preventively or taking the pill right after contamination or supposed contamination, do you think we will be able to change the incidence of HIV infection in the future?
There is research to try and improve these strategies through long-acting pills and implants. These strategies are still at the research stage for patients who are already infected, to allow them to be well protected without taking their pills every day. And the expectation is that, once this is proven to be highly efficient in patients, it might be translated in the future for prevention, but this is not yet the case.
Can you tell us about the major health problems people with HIV can experience?
The anti-retroviral treatment of HIV has unmasked another complication of the HIV infection, which is the chronic inflammation caused by this persistent infection. If you treat it with antiretroviral drugs, which block the virus very early after contamination, the chronic inflammation has no time to be harmful for the body. If the diagnosis is made at a later stage, after years of infection, even if it is made before the AIDS stage, then the patient has suffered from chronic inflammation which has damaged the vessels, the cardio-vascular system. The new WHO recommendation to provide treatment immediately means that these cardiovascular complications are decreasing.
Do you think the inflammatory process associated with HIV infection and/or the immunosuppression treatment of HIV are responsible for accelerated ageing in some patients?
Some treatments can increase the risk, but these treatments are generally no longer used. So, one can consider that the higher incidence of cardiovascular disease and the increased ageing of HIV patients is due to inflammation rather than treatment. And the sooner the patients are treated, the better it is for this complication.
I think that’s an important message. In your opinion, do the comorbidities associated with HIV contribute to the morbidity and mortality of these patients?
Yes of course. We have the comorbidities associated with the increased frequency of cardiovascular disease. We also have a direct effect on metabolism, with increased levels of lipids, triglycerides, cholesterol, higher incidence of diabetes - and again this is considered to be mostly due to HIV and inflammation caused by HIV, and partially due to treatments. The recommendation now is to use treatments which are less associated with these comorbidities.
HIV induces risk in terms of cardiovascular disease, diabetes and cancer. As the HIV population ages, how do you think it will be impacted by comorbidities?
Currently the HIV-infected population undergoing treatment with antiretroviral drugs lives almost normally, but still has a higher incidence of cancer compared to the general population of the same age. But these cancers are of two types, and they are associated with some risk factors for HIV. For example, HIV-infected patients are often smokers, and one of the most frequently observed cancers in HIV-infected patients nowadays is lung cancer. This lung cancer benefits from the same new therapies that we mentioned before, but it’s a very severe cancer. Another frequent cancer observed in treated patients is cancer of the lymph nodes, which again benefits from the new therapies. There are also other cancers which are caused by viruses frequently associated with HIV - Hepatitis C, Hepatitis B, Papilloma virus, Kaposi sarcoma virus - so we are still seeing an increased frequency of virus-associated cancers in treated HIV-infected patients.
The expectation in the future is that the frequency of cancers in optimally treated HIV patients will soon become the same as in the general population.
I understand now that we should treat these patients as early as possible to prevent any comorbidities and complications that may affect survival.
This early treatment has two major benefits: one in terms of public health, because it blocks contamination, and one for the individual patients, whose life expectancy will increase.
About the authors
Professor Autran is the Director of the Immunology Department and the Medical Biology and Pathology Hub at the Pitié-Salpêtrière Hospital in France, where she leads the "Anti-viral and Vaccinal Immunity and Immunogenetics" research team.
Eric Raymond is a Professor of Medical Oncology at Paris Saint-Joseph Hospital and a Medical Director at SCOR Global Life. He is Board-certified in Medical Oncology and has a PhD in Cellular and Molecular Biology. Professor Raymond is a former Professor of Oncology at the University of Paris VII, the former Chair of Medical Oncology at Bichat-Beaujon University Hospitals, Clichy, France and a former Professor of Medical Oncology at CHUV/UNIL in Lausanne, Switzerland.