Based on the results, the study authors recommended implementing strategies to reduce smoking, and therefore lung cancer risk, in HIV-positive adults.

The study authors also speculated that links between lung cancer and HIV or immune deficiency in previous studies were caused by overrepresentation of people with advanced HIV infections in lung cancer studies or accidental inclusion of cancers known to be caused by infectious diseases, such as Kaposi’s sarcoma of the lung.

According to the study authors, previous research has shown that people with HIV are at about a two- to seven-fold increased risk for lung cancer compared to people without HIV (see related AIDS Beacon news). However, scientists are uncertain whether this higher risk arises from HIV or from lifestyle factors, such as a greater rate of smoking in people with HIV.

According to the study authors, while people with HIV are known to be more likely to smoke than people without HIV, some studies have shown that HIV-positive adults with lower CD4 (white blood cell) counts are more likely to develop lung cancer than adults with higher CD4 counts. This might suggest that weakened immune systems caused by HIV are also a factor in higher lung cancer rates among people with HIV.

The authors also noted that HIV can lead to a greater risk for lung infections such as pneumonia or tuberculosis, which could play role in increased lung cancer risk.

In this study, the researchers aimed to determine whether HIV infection is a factor in higher lung cancer risk in people with HIV or whether the increased risk is due solely to lifestyle factors, especially smoking.

The study included 68 HIV-positive Swiss adults who developed lung cancer between 1985 and 2010. The study also included 337 HIV-positive Swiss adults without lung cancer who were matched by age (within nine years), sex, treatment center in Switzerland, route of HIV infection (sexual, injection drug use, etc.), and date enrolled in the study.

The researchers collected information on each participant’s CD4 counts, viral loads (amount of HIV in the blood), nadir CD4 count (the lowest CD4 count measured after HIV infection), antiretroviral therapy regimen, and smoking habits. They also examined their medical records for any HIV-related lung infections.

Most of the participants (79 percent) were male, and 37 percent were intravenous drug users, who are known to be at higher risk of lung cancer. Participants who had cancer developed it at an average age of 50 years old; 86 percent died within two years of diagnosis.

Results showed that participants who currently smoked were over 14 times more likely to develop lung cancer than participants who had never smoked, with an increased risk in patients with heavier smoking habits. Participants who were former smokers were about three times more likely to develop lung cancer, although the study authors stated that the difference was not statistically significant.

Contrary to results from other studies, lung cancer risk was not associated with nadir CD4 count, CD4 count within a year of lung cancer diagnosis, or CD4 count one to two years before diagnosis. There was no difference in average CD4 counts between participants who developed lung cancer and those who did not, for up to 10 years prior to lung cancer diagnosis.

The researchers also found no link between lung cancer and viral load, taking or not taking antiretrovirals, or history of HIV-related lung infections.

For more information, please see the study in the British Journal of Cancer (abstract).

The study authors suggested that a weakened immune system underlies the increased cancer rate.

“Our findings show that there is a need for prevention and early diagnosis of cancers related to infectious agents (such as cervical cancer, Kaposi’s sarcoma, lymphoma, gastric carcinoma) in the HIV-infected population, because they are of higher incidence, especially in individuals with CD4 counts below 500,” said Dr. Ana Katherine da Silveira Gonçalves of the Universidade Federal do Rio Grande do Norte in Brazil, and lead author of the study.

“In addition, these patients should see their doctor at shorter intervals than those recommended for uninfected people, in order to detect early lesions that can turn into cancer more quickly, since low immunity favors tumor growth,” she added.

Dr. Joel Palefsky, a professor of medicine at the University of California, San Francisco, who was not affiliated with the study, agreed that people with HIV will need to watch for cancer. “As people with HIV live longer, [these results] mean that they will need to be monitored for other potential causes of morbidity and mortality, such as various cancers,” said Dr. Palefsky.

Dr. Palefsky noted that HIV-positive people with a low nadir CD4 count (the lowest CD4 (white blood cell) count measured after HIV infection) before antiretroviral therapy may suffer more immune damage than transplant recipients, leading to increased cancer susceptibility.

According to the authors of the study, the results could be useful in designing strategies for cancer prevention or early detection in people with HIV. “An effective strategy would be to recommend that the patients undergo preventive exams more frequently than non-HIV/transplant populations. These exams are low-cost and highly effective at detecting cancer precursor lesions and carcinomas in this specific population,” said Dr. Gonçalves.

Dr. Palefsky also recommended several steps for people with HIV that might help with cancer prevention and detection. “I would advise all HIV-positive people to stop smoking if possible. I also believe that everyone should have an annual digital ano-rectal exam to feel for lumps that could indicate the presence of anal cancer,” he said.

Previous studies have shown that, in addition to its role in fighting infections, the immune system also identifies and kills cancer cells. People with decreased immunity therefore have an increased risk of developing cancer.

Previous studies have also shown that people with HIV are more prone to certain cancers, such as anal cancer, Hodgkin’s lymphoma, and others (see related AIDS Beacon news). In some cases researchers believe this is related to decreased immune function in people with HIV.

Several studies have compared the risk of developing cancer in HIV patients (see related AIDS Beacon news) or transplant recipients to the general population. Transplant patients also have a weak immune system, since they are treated with drugs that suppress the immune system to prevent rejection of the transplanted organ.

In this study, researchers reviewed data from several such previous studies to evaluate the rate of cancer in HIV-positive people and transplant recipients, in order to see what role decreased immunity might play in cancer development in these populations. They also investigated whether particular types of cancer occur more frequently in either group, with the goal of helping to guide strategies for decreasing any cancers specifically related to immune suppression.

Nineteen studies of cancer rates in HIV patients, and six studies in transplant recipients (primarily kidney transplant patients), were included in the analysis.

Results showed that people with HIV were four times as likely as the general population to develop cancer. Transplant recipients were over three times as likely to develop cancer.

According to the study authors, infectious agents such as the Epstein-Barr virus trigger some types of cancer. In particular, Kaposi’s sarcoma, Hodgkin’s lymphoma, and some liver, stomach, anal, and oral cancers are thought to be related to infectious agents.

Results showed that infectious agent-related cancers were particularly increased in HIV patients and transplant recipients. For instance, infection by the bacterium Helicobacter pylori is strongly associated with the development of stomach cancer. The results showed that the rates of stomach cancer were doubled in HIV-positive people and transplant recipients as compared to the general population.

The authors suggested that decreased immunity in these two groups of people may result in increased exposure to infectious agents, and therefore increased rates of such cancers.

Other cancers, such as those of the colon, rectum, breast, ovary, and prostate, were not increased in either population.

Some cancers occurred more frequently in one group, but not the other. Kidney and thyroid cancers occurred at increased rates in transplant recipients, but not people with HIV. Brain cancer occurred at increased rates in people with HIV, but not transplant patients.

The researchers noted that the reasons for the differences are currently unknown, but speculated that they were due to differences in lifestyle.

For more information, please see the study in the journal Cancer Epidemiology (abstract).

However, the study authors also found that greater viral loads may predict decreased treatment efficacy.

Based on their results, the authors stated that plans for radiation therapy and the prescribed doses used do not necessarily need to be altered for HIV-positive men with prostate cancer.

In men, prostate cancer is the third most common cause of death from cancer; in men over the age of 75 it is the most common cause of death from cancer.

As the life expectancy of people with HIV rises, diagnosis and treatment of prostate cancer in HIV-positive men will become increasingly important.

In this study, researchers examined the safety and efficacy of external-beam radiotherapy (EBRT) for prostate cancer in HIV-positive men compared with HIV-negative men. EBRT is the most common form of radiotherapy and involves an external source of radiation that is pointed at the tumor, in this case within the prostate.

The researchers retrospectively analyzed the medical records of 13 HIV-positive men with prostate cancer and 26 HIV-negative men with prostate cancer. Patients were followed for a median of 39 months.

The average age for the HIV-positive group was 55 years old compared with 60 years old for the HIV-negative comparison group. Most patients (77 percent) were African American.

Sixty-two percent of the HIV-positive men in the study were receiving highly active antiretroviral therapy (HAART) at the time of diagnosis with prostate cancer. In addition, one patient started HAART just before beginning radiation therapy.

Most patients (77 percent) received radiation specifically to the prostate. The rest received radiation to the entire pelvis.

Results showed that the 4-year biochemical failure-free survival rate – as shown by stable prostate-specific antigen levels, a protein thought to be a marker of prostate cancer – was 87 percent in HIV-positive patients and 89 percent in control group patients. The difference in survival between the two groups was not statistically significant.

Overall, 23 percent of the HIV-positive men experienced a biochemical failure compared with 12 percent of HIV-negative patients; this difference was also not statistically significant. None of the HIV-positive men died during the course of the study.

Higher viral loads (amount of HIV in the blood) before and after radiation therapy were associated with increased risk of biochemical failure.

Results also showed that patients with HIV were less likely to experience side effects from radiation therapy. Nearly half (46 percent) of HIV-positive patients experienced no acute side effects of the reproductive and urinary systems or the stomach and intestines, compared to 4 percent to 8 percent of HIV-negative men.

However, due to the small size of the study and its retrospective nature, the researchers noted that it cannot be concluded that HIV-positive people have higher tolerance for radiation therapy.

Results also showed that CD4 (white blood cell) counts decreased following radiation therapy for 85 percent of the HIV-positive patients. In addition, 54 percent of the patients with HIV experienced an increase in viral load following radiation therapy.

The average decrease in CD4 counts for HIV-positive patients was 193 cells per microliter. The average increase in viral loads was about 6,800 copies per milliliter.

HIV-positive patients receiving whole-pelvis radiation experienced similar declines in CD4 cell counts as patients receiving radiation directed at the prostate only. The researchers suggested that a stress response to radiation therapy may account for the decline in CD4 cell counts.

Declines in CD4 counts were not permanent, and no patients had HIV-related complications or opportunistic infections during follow-up that were related to radiation therapy.

For more information, please see the study in the International Journal of Radiation Oncology∙Biology∙Physics (abstract).

Gilead Receives Approval For Eviplera In Europe – The European Medicines Agency (EMA) has approved Gilead Sciences’ new once-daily combination antiretroviral pill Eviplera (rilpivirine/emtricitabine/tenofovir) for the treatment of HIV in previously untreated adults with viral loads (amount of HIV in the blood) of 100,000 copies per milliliter or less. The approval means that Eviplera can be marketed in all 27 countries in the European Union. Eviplera, known as Complera in the U.S., was approved by the U.S. Food and Drug Administration in August. For more information, please see the Gilead Sciences press release.

AIDS Deaths Continue To Drop Worldwide – An annual report from the United Nations shows that the number of deaths worldwide due to AIDS has continued to drop for the third year in a row. The number of new HIV infections also fell 21 percent in 2010 compared to 1997; 70 percent of new infections were in sub-Saharan Africa. However, the number of people on antiretrovirals increased 20 percent in 2010 in sub-Saharan Africa, bringing the total to 50 percent of clinically eligible people with HIV in low- and middle-income countries. The report also notes that due to longer lifespans and greater survival rates, the number of people living with HIV now stands at an estimated 34 million, the highest ever. For more information, please see the United Nations report (pdf) or the article in the Washington Post.

Study Finds Viread Vaginal Gel Is Safe But Ineffective For HIV Prevention – Results from the Oral Interventions to Control the Epidemic (VOICE) study indicate that a vaginal gel containing 1 percent Viread (tenofovir) is safe but ineffective at preventing HIV infection in women. Based on the results, the National Institutes of Health, which is funding the study, has decided to drop the vaginal gel from the study. The trial, whose purpose is to provide women with methods to prevent HIV infection, will continue to evaluate the safety and efficacy of Truvada (emtricitabine/tenofovir) pills instead. The VOICE study was first modified in September after results showed that a Viread pill was also ineffective (see related AIDS Beacon news). For more information, please see the National Institutes of Health press release.

The study authors also said that a comparison of their results with studies of HIV-negative, older adults suggests that people with HIV have around a three- to four-fold higher risk for cancer and heart attacks and a five-fold higher risk for diabetes than people of the same age without HIV.

Based on their results, the authors recommended that older adults with HIV be screened for additional illnesses and try to minimize risk factors for these diseases, such as being overweight.

With the advent of highly active antiretroviral therapy (HAART), many people with HIV are living well into older age; a recent study found that life expectancy for people with HIV is now close to that of people without HIV (see related AIDS Beacon news). In addition, the rate of new HIV infections in older adults continues to rise.

As people with HIV age, however, they become more prone to many of the same age-related illnesses as people without HIV, including cancer, heart disease, and diabetes.

According to the study authors, previous studies have looked at the rates of individual diseases, such as diabetes, in aging people with HIV; however, few studies have looked at the rates of age-related diseases overall in this population.

In this study, the researchers aimed to determine the rates of such age-related diseases in people with HIV aged 50 and above compared to younger adults with HIV.

The study included 8,444 HIV-positive adults aged 16 years or older, with a median age of 45 years old. Most participants (71 percent) were male. The median age at HIV diagnosis was 29 years old, and the median length of HIV infection was 15.4 years.

The researchers categorized participants into three age groups: younger than 50 (68 percent of participants), 50 to 64 years old (26 percent), and 65 or older (5 percent).

Results showed that participants older than age 50 were more likely to have other illnesses and to die than participants younger than 50. In particular, older participants were at a higher risk for bacterial pneumonia, stroke, blocked coronary (heart) arteries, heart attack, bone fractures, osteoporosis, diabetes, inflammation of the pancreas, and non-AIDS-defining cancers.

The risks remained higher in older participants after adjusting for CD4 (white blood cell) counts, viral loads (amount of HIV in the blood), sex, current or former smoking, current or former injection drug use, and length of HIV infection.

However, older study participants were not at a higher risk of HIV-related illnesses.

Results also showed that female participants had about a three-fold higher risk of osteoporosis than male participants.

In addition, former injection drug users were at a higher risk of bacterial pneumonia, liver problems, and death; current injection drug users were at a higher risk of liver problems and death. Former smokers were at a higher risk of death; current smokers were at a higher risk of bacterial pneumonia and death.

Higher CD4 counts were linked to a slightly lower risk of bacterial pneumonia, bone fractures due to bone fragility, osteoporosis, new AIDS-defining illnesses, and death. Higher viral loads were associated with an increased risk of HIV-related illnesses.

Study participants with longer HIV infections were slightly less likely to develop HIV-related illnesses.

During the course of the study, 2 percent of participants died. The leading causes of death were cancer (23 percent), infectious diseases (15 percent), and heart-related diseases (12 percent).

A comparison with other European studies on illnesses in aging HIV-negative adults suggested that people with HIV were about 4 times more likely to get cancer, 3.5 times more likely to have a heart attack, and over 5 times more likely to have diabetes than people of the same age without HIV.

However, the study authors noted that these are just estimates, since their study did not include a matched HIV-negative study population for a true comparison.

For more information, please see the study in Clinical Infectious Diseases (abstract).

The authors of the review recommended that in certain cases, patients should consider switching drug regimens or stopping antiretroviral therapy during chemotherapy.

The authors also emphasized the need for more clinical trial data about the combined use of antiretroviral therapy and anti-cancer drugs in patients with both cancer and HIV.

With the introduction of highly active antiretroviral therapy (HAART), AIDS-related complications and death have become less common; AIDS-defining cancers like Kaposi’s sarcoma, non-Hodgkin’s lymphoma, and cervical cancer have decreased.

However, non-AIDS-defining cancers, including Hodgkin’s lymphoma and anal, lung, and testicular cancer, have become more common in HIV-positive people (see related AIDS Beacon news).

As a result, information about potential drug interactions and the combination of antiretroviral and cancer drugs in HIV-positive cancer patients is increasingly important. To date, little is known about the possible overlapping side effects of antiretrovirals and cancer drugs and the interactions of the two different types of drugs.

Antiretrovirals May Worsen Side Effects Of Certain Cancer Drugs

One major concern about combining antiretroviral therapy and chemotherapy is the potential for overlapping side effects. Several antiretrovirals have similar side effects as certain chemotherapy agents, and combining the two may increase the rate or severity of these effects.

Several of the side effect concerns deal with older antiretrovirals. Zidovudine (Retrovir), for example, has been associated with low white blood cell counts (neutropenia), which puts some patients at risk for infections. Many chemotherapy regimens are also associated with low white blood cell counts.

The review authors recommended that an alternative to zidovudine be used when possible during chemotherapy; if not, chemotherapy drugs that have less effect on white blood cells should be used and the patient’s white blood cell count should be carefully monitored.

Other anti-HIV drugs like didanosine (Videx) and stavudine (Zerit) are often associated with peripheral neuropathy, a nerve condition that causes pain, numbness, or tingling in the extremities. Since some classes of cancer drugs, specifically platinums (e.g., cisplatin, carboplatin), taxanes (such as paclitaxel (Taxol), Taxotere (docetaxel)), and vinca-alkaloids (e.g., vincristine (Oncovin), vinblastine (Velban)), may also cause peripheral neuropathy, the review authors recommended that physicians substitute a different chemotherapy drug with fewer overlapping side effects, substitute a different antiretroviral, or ask patients to temporarily discontinue antiretroviral therapy.

Some newer antiretrovirals may also cause problems when combined with chemotherapy drugs. The anti-HIV drugs Reyataz (atazanavir), Kaletra (lopinavir/ritonavir), and Invirase (saquinavir mesylate) are associated with longer QT intervals, a problem in which the heart takes an abnormally long time to recharge between beats.

Several anticancer drugs – including anthracyclines such as doxorubicin (Adriamycin) or daunorubicin (Cerubidine), arsenic trioxide (Trisenox), Sprycel (dasatinib), Tykerb (lapatinib), Tasigna (nilotinib), Sutent (sunitinib), and tamoxifen – are also linked with longer QT intervals. Because of the risk of sudden death associated with long QT intervals, the review authors recommended avoiding combinations of these drugs.

The authors noted that newer anticancer agents are more selective at killing cancer cells and may cause fewer side effects.

Interactions Between Anticancer Drugs And Antiretrovirals

Since antiretrovirals and chemotherapy drugs are often metabolized by the body in the same way, there is a high potential for drug-drug interactions. These may result in drug concentrations in the blood that are higher or lower than expected, leading to more side effects or reduced efficacy.

Since not many studies have been conducted on antiretroviral-chemotherapy drug interactions, scientists have tried to predict which drugs may interact based on what is known about how the drugs are metabolized.

In terms of antiretrovirals, the reviewers noted that Norvir (ritonavir)-boosted regimens may be of concern because Norvir is known to affect an enzyme that metabolizes many cancer drugs. Many physicians search for alternatives to Norvir-based regimens during chemotherapy.

Preliminary results from a study on Sutent presented this week at the American Society of Clinical Oncology meeting suggest that patients taking Norvir-based antiretroviral therapy may be more likely to experience side effects. The study, part of the AIDS Malignancy Consortium set of clinical trials, is one of the first to investigate drug-drug interactions for chemotherapy drugs and antiretrovirals.

For chemotherapy drugs, the reviewers suggested, based on drug interaction predictions, that anticancer drugs like camptothecins (e.g., Hycamtin (topotecan), irinotecan (Camptosar)), alkylating agents (such as melphalan (Alkeran), busulfan), corticosteroids (e.g., dexamethasone (Decadron), prednisone), epipodophyllotoxins (such as etoposide, Vumon (teniposide)), taxanes, tyrosine-kinase inhibitors (e.g., Gleevec (imatinib), Sutent), and vinca-alkaloids may be especially likely to be affected by HAART.

There is also some evidence from case studies that Targretin (bexarotene), cyclophosphamide (Cytoxan), Taxotere, irinotecan, and vinblastine might interact with antiretroviral drugs.

According to the review authors, there is currently no guidance for dose adjustments of antiretroviral or chemotherapy drugs, partly because patients with HIV were excluded from early cancer treatment trials. Although the exclusion of HIV patients from cancer treatment trials is no longer allowed, the study authors indicated that it may take several years before guidelines will be available.

The authors noted that maintenance of the chemotherapy dosing and schedule is thought to be most important in treating cancer, and therefore cancer treatment must sometimes take priority over HIV treatment, despite the risks associated with stopping HAART. However, they also stated that oncologists must recognize that continuous HAART is necessary to prevent resistant strains of HIV, opportunistic infections, and eventual death.

For more information, please see the article in The Lancet (abstract).

HIV controllers are individuals infected with HIV whose immune systems are able to naturally control the virus, meaning they have low or undetectable viral loads (amount of HIV in the blood) without the use of antiretroviral drugs. HIV controllers typically also have a significantly slower decline in their number of CD4 cells (white blood cells that are targeted and infected by HIV).

“Even for these patients [HIV controllers], a prolonged follow-up is necessary since some of them lose their CD4 [cells], even after more than 15 years of virological control of HIV infection,” said Dr. Faroudy Boufassa, the principal investigator of the study, in correspondence with The AIDS Beacon.

The authors of the study suggested that a possible reason for the decline in CD4 cells and HIV disease progression is chronic inflammation and immune activation caused by CD8 cells, immune cells important in suppressing the HIV virus.

However, Dr. Boufassa noted that the decline in CD4 cells may be due to many reasons. “We are absolutely convinced that viral blips are probably multifactorial,” said Dr. Boufassa. He suggested that other factors that affect the immune system, such as vaccines, co-infection with other sexually transmitted infections, or illnesses such as the flu, could play a role.

The authors plan to further study the long-term prognosis of HIV controllers, including how viral load blips and CD4 count declines might relate to cancer risk.

Researchers have long been interested in understanding how HIV controllers manage HIV and avoid disease progression, since this could help with identification of new methods to treat people with HIV or development of an HIV vaccine.

Few studies on HIV controllers have investigated their long-term CD4 cell count characteristics after HIV diagnosis. In this study, the authors investigated CD4 cell counts and disease outcomes in 81 HIV controllers recruited between 2006 and 2007.

The researchers defined HIV controllers as individuals with untreated HIV infection, no symptoms for more than 10 years, and whose viral loads have been below 400 copies per milliliter of blood in more than 90 percent of samples since HIV diagnosis.

Forty-three percent of the HIV controllers were women, 84 percent were Caucasian, and 85 percent were heterosexual. The median age at HIV diagnosis was 29 years, and the median age at study enrollment was 45 years.

The researchers collected each participant’s previous CD4 cell counts and viral load measurements. They also measured participants’ CD4 counts and viral loads throughout the study period.

At the time of enrollment, the median CD4 cell count was 741 cells per microliter of blood. Viral load was below 400 copies per milliliter of blood in 96 percent of the HIV controllers.

Based on viral loads since HIV diagnosis, the HIV controllers were divided into three groups: a “no blip” group, in which patients always had viral loads below the detection limit; a “rare blips” group, in which fewer than 50 percent of viral loads were above the detection limit; and a “frequent blips” group, in which more than 50 percent of viral loads were above the detection limit.

Results showed that at the time of enrollment, the median CD4 cell count was significantly higher in the “no blip” group than in the other two groups (819 cells per microliter, versus 644 cells per microliter for the “rare blips” group and 628 cells per microliter for the “frequent blips” group).

Additionally, CD4 cell counts declined significantly in the “rare blips” and “frequent blips” groups while the “no blip” group had no decline in CD4 cells. The researchers estimated that an HIV controller with rare or frequent blips who had a CD4 count of 903 cells per microliter at diagnosis would reach 830 cells per microliter after five years, 760 cells per microliter after 10 years, and 629 cells per microliter after 20 years.

During the study period, three participants from the “rare” or “frequent” blips groups experienced HIV disease progression, characterized by a drop in CD4 cell count to below 200 cells per microliter of blood. One of these participants also experienced a sustained viral load above 1,000 copies per milliliter.

Four HIV controllers from the two “blips” groups developed cancer, including one of the participants whose CD4 counts dropped below 200 cells per microliter. Two patients died, one from heart disease and the other from an unknown cause.

The researchers found no signs of disease progression or cancer in the “no blip” group of HIV controllers.

For more information, please see the study in PLoS One.

“Los cambios en el número y los tipos de cáncer en las personas con VIH/SIDA destacan la necesidad de investigaciones que se centren en las necesidades de prevención del cáncer específicas para esta población, incluyendo el dejar de fumar, el tratamiento de la hepatitis B y C, las infecciones virales y la prevención y detección de cánceres relacionados con el VPH”, dijo el Dr. Eric A. Engels, investigador principal del estudio del Instituto Nacional del Cáncer (NCI, por sus siglas en inglés), en un comunicado de prensa.

Hoy en día, el cáncer es la principal causa de muerte de las personas con VIH. Algunos estudios han estimado que a entre un 30 y un 40 por ciento de las personas con VIH se les diagnosticará cáncer.

Los cánceres determinantes del SIDA son aquellos cánceres comunes en las personas con infecciones avanzadas de VIH, debido al debilitamiento de su sistema inmunológico, incluyendo el sarcoma de Kaposi, el linfoma no Hodgkin y el cáncer del cuello uterino. A pesar de que pueden aparecer en personas libres del VIH, el desarrollo de estos tipos de cáncer en una persona con VIH está estrechamente ligado al estado de su sistema inmunológico. Es por ello cuando una persona con VIH desarrolla un cáncer determinante del SIDA, se suele considerar que esa persona tiene SIDA.

Existen estudios previos que indican que las tasas de cánceres determinantes del SIDA han disminuido como resultado de la mejora de la salud lograda gracias a la terapia antirretroviral, en particular gracias a la terapia antirretroviral de alta actividad (HAART, por sus siglas en inglés) (vea una noticia relacionada en el AIDS Beacon, en inglés).

En contraste, la aparición de un cáncer no determinante del SIDA no lleva a ser diagnosticado con SIDA. Algunos cánceres no determinantes del SIDA se dan con más frecuencia en las personas con VIH que en la población general, pero pueden darse incluso en el caso de personas que llevan un control muy cuidadoso para prevenir la infección por el VIH.

A medida que la expectativa de vida de las personas con VIH aumenta, también lo hace el riesgo de desarrollar tipos de cáncer no determinantes del SIDA, como el linfoma de Hodgkin, el cáncer de pulmón y el cáncer de ano.

Un estudio del NCI confirma el descenso de cánceres determinantes del SIDA y el aumento de cánceres no determinantes del SIDA

Los resultados del estudio del NCI, llevado a cabo conjuntamente con los Centros para el Control y Prevención de Enfermedades, confirmaron los resultados de estudios anteriores que indicaban que las tasas de cánceres determinantes del SIDA han disminuido, pero las tasas de cánceres no determinantes del SIDA están aumentando en las personas con SIDA.

Los autores del estudio atribuyen el aumento de los cánceres no determinantes del SIDA a que la población con SIDA está envejeciendo y también tiene una mayor preponderancia de factores de riesgo en comparación con el resto de la población, como el tabaquismo y la infección por hepatitis C.

Los investigadores estimaron el número de casos de cáncer en la población con SIDA comparando los registros del VIH con los registros de cáncer en 34 estados. Los resultados demostraron que entre 1991 y 2005 se registraron casi 80,000 casos de cáncer en personas con SIDA.

Un análisis más detallado demostró que entre 1991 y 1995, y entre 2001 y 2005, el número de cánceres determinantes del SIDA se redujo unas tres veces, mientras que el número de cánceres no determinantes del SIDA se triplicó. Durante los mismos períodos, la población con SIDA aproximadamente se cuadruplicó.

El número de cánceres de ano fue el que más aumentó durante estos períodos, multiplicándose aproximadamente por ocho. La incidencia del cáncer de hígado se multiplicó por cinco, mientras que las tasas de cáncer de pulmón y linfoma de Hodgkin se duplicaron.

Un estudio belga demuestra que la edad y unas cuentas de células CD4 en el mínimo son factores de riesgo para cánceres no determinantes del SIDA

Los resultados de otro estudio más pequeño realizado en Bélgica han revelado que los factores de riesgo primarios para los cánceres no determinantes del SIDA son tener más de 45 años y presentar valores mínimos (nadir) en la cuenta de células CD4 (menos de 200 células por microlitro de sangre). El nadir de la cuenta de células CD4 se define como la menor cuenta de células CD4 medida después de la infección por el VIH.

En su estudio, los científicos belgas investigaron la incidencia, los factores de riesgo, y los resultados clínicos de cánceres no determinantes del SIDA en 3,126 adultos con VIH pertenecientes al grupo de VIH del St-Pierre de Bruselas. Los investigadores examinaron las historias clínicas de estos pacientes entre enero del 2002 y marzo del 2009.

Durante este período, 45 personas con VIH fueron diagnosticadas con cánceres no determinantes del SIDA.

En concordancia con los resultados del estudio del NCI, los investigadores observaron una mayor prevalencia del linfoma de Hodgkin, el cáncer de ano y el cáncer de hígado en las personas con VIH, en particular en los hombres, en comparación con la población general. Las mujeres con VIH presentaron tasas más altas del linfoma de Hodgkin y el cáncer de vejiga, aunque presentaron menores tasas de cáncer de mama en comparación con las mujeres en la población general.

Aproximadamente un 53 por ciento de los pacientes con cáncer eran mayores de 45 años, en comparación con un 22 por ciento de los pacientes sin cáncer. Además, el nadir en las cuentas de células CD4 de los pacientes con VIH y cáncer fue menor (un promedio de 110 células por microlitro) que en las personas con VIH y sin cáncer (un promedio de 224 células por microlitro).

Los pacientes con VIH y cánceres no determinantes del SIDA tenían una historia de infección por el VIH más larga y una tasa dos veces mayor de infección por hepatitis C.

Los resultados también indicaron que los adultos con VIH y cáncer tienen un riesgo de muerte 15 veces mayor que los pacientes con VIH no diagnosticados con cáncer. Los hombres vivieron más tiempo después del diagnóstico del cáncer (32 meses) que las pacientes del sexo femenino (14 meses). Las mujeres que eran emigrantes del África subsahariana mostraron un pronóstico especialmente malo, posiblemente debido a factores socioeconómicos como sus bajos recursos.

Alrededor del 54 por ciento de los pacientes con cáncer de y VIH recibieron quimioterapia. Un 32 por ciento de estos pacientes experimentaron complicaciones relacionadas con infecciones, y un 28 por ciento tuvo complicaciones relacionadas con la sangre, siendo la anemia (disminución del número de glóbulos rojos) la más común.

Además, el 41 por ciento de los pacientes con cáncer fueron sometidos a cirugía, con una tasa de complicaciones del 32 por ciento, incluyendo dos muertes. Un 43 por ciento de los pacientes recibieron radioterapia, de los que un 25 por ciento sufrió complicaciones, la mayoría de ellas erupciones.

Para obtener más información sobre el estudio del NCI, por favor, consulte el Journal of the National Cancer Institute (resumen, en inglés) o el comunicado de prensa del NCI (en inglés). Para obtener más información sobre el estudio belga, por favor consulte el Journal of the International AIDS Society (en inglés).

“The changing number and types of cancer for people with HIV/AIDS highlights the need for research focusing on the specific cancer prevention needs of this population, including smoking cessation, treatment of hepatitis B and C viral infections, and prevention and screening for HPV-related cancers,” said Dr. Eric A. Engels, lead investigator of the National Cancer Institute (NCI) study, in a press release.

Cancer is now a leading cause of death for people with HIV. Some studies have estimated that about 30 percent to 40 percent of people with HIV will be diagnosed with cancer.

AIDS-defining cancers are cancers that are common in people with advanced HIV infections as a result of their weakened immune systems. These types of cancer include Kaposi’s sarcoma, non-Hodgkin’s lymphoma, and cervical cancer. Although they can appear in people who are HIV-negative, the development of these cancers in a person with HIV is closely tied to the health of the immune system. As a result, a person with HIV who has an AIDS-defining cancer is usually classified as having AIDS.

Previous studies have indicated that rates of AIDS-defining cancers have decreased as a result of improved health due to antiretroviral therapy, particularly highly active antiretroviral therapy (HAART) (see related AIDS Beacon news).

In contrast, developing a non-AIDS-defining cancer does not lead to a diagnosis of AIDS. Non-AIDS-defining cancers are in some cases more common in people with HIV than in the general population, but can occur even in people who carefully control their HIV infection.

As the life spans of people with HIV are increasing, so is their risk of developing non-AIDS-defining cancers, such as Hodgkin’s lymphoma, lung cancer, and anal cancer.

NCI Study Confirms Drop In AIDS-Defining Cancers, Rise In Non-AIDS-Defining Cancers

Results from the NCI study, carried out jointly with the Centers for Disease Control and Prevention, confirmed results of previous studies indicating that the rates of AIDS-defining cancers have dropped but the rates of non-AIDS-defining cancers are increasing in people with AIDS.

The study authors attributed the increase in non-AIDS-defining cancers to an aging AIDS population and a higher prevalence of risk factors such as smoking and hepatitis C infection compared to the general population.

The researchers estimated the number of cancers in the AIDS population by comparing HIV registries with cancer registries in 34 states. Results showed that from 1991 to 2005, nearly 80,000 cancers were reported in people with AIDS.

Further analysis showed that between 1991 to 1995 and 2001 to 2005, the number of AIDS-defining cancers dropped about three-fold while the number of non-AIDS-defining cancers increased three-fold. During the same time period, the AIDS population approximately quadrupled.

Anal cancers increased the most during this period, approximately eight-fold. Liver cancers increased five-fold, and lung cancers and Hodgkin’s lymphoma rates doubled.

Belgian Study Finds Older Age, Low Minimum CD4 Counts Are Risk Factors For Non-AIDS-Defining Cancers

Results from a second smaller study from Belgium showed that the primary risk factors for non-AIDS-defining cancers are age over 45 years and low minimum (nadir) CD4 cell counts (less than 200 cells per microliter of blood). The nadir CD4 cell count is defined as the lowest CD4 cell count measured after HIV infection.

In their study, the researchers from Belgium investigated the occurrence, risk factors, and outcomes of non-AIDS-defining cancers in 3,126 HIV-positive adults from the Brussels St-Pierre HIV cohort. They examined the medical records for these patients from January 2002 to March 2009.

During this period, 45 HIV-positive individuals were diagnosed with non-AIDS-defining cancers.

Consistent with the NCI study results, the researchers observed a higher rate of Hodgkin’s lymphoma, anal cancer, and liver cancer in people with HIV, particularly men, compared to the general population. HIV-positive women had higher rates of Hodgkin’s lymphoma and bladder cancer but lower rates of breast cancer compared to women in the general population.

Approximately 53 percent of patients with cancer were over the age of 45 years, compared to about 22 percent of patients without cancer. In addition, HIV-positive cancer patients had lower nadir CD4 cell counts (an average of 110 cells per microliter) compared to HIV-positive individuals without cancer (an average of 224 cells per microliter).

HIV patients with non-AIDS-defining cancers had a longer history of HIV infection and a two-fold higher rate of hepatitis C infection.

Results also indicated a 15-fold increase in risk of death for HIV-positive adults with cancer compared to individuals not diagnosed with cancer. Male patients lived longer after cancer diagnosis (32 months) than female patients (14 months). Women who had emigrated from sub-Saharan Africa had a particularly poor prognosis, possibly due to socio-economic factors such as low income.

About 54 percent of the HIV-positive cancer patients received chemotherapy. Thirty-two percent of these patients experienced complications related to infections, and 28 percent experienced blood complications, with anemia (a decrease in the number of red blood cells) being the most common.

In addition, 41 percent of cancer patients underwent surgery, with a complication rate of 32 percent, including two deaths. Forty-three percent of patients had radiotherapy, with 25 percent reporting complications, mostly rashes.

For more information on the NCI study, please see the Journal of the National Cancer Institute (abstract) or the NCI press release. For more information on the Belgian study, please see the Journal of the International AIDS Society.

AIDS Patients May Have A Higher Risk Of Developing Stomach And Esophageal Cancers – Results of a recent study suggest that AIDS patients have a higher risk of developing stomach and esophageal cancers. Scientists at the National Cancer Institute analyzed data from nearly 600,000 AIDS patients. Of those, 1,666 developed stomach cancers, while 240 developed esophageal cancers. Patients with AIDS had a nearly seven-fold greater chance of developing stomach cancer and an almost three-fold greater chance of developing esophageal cancer when compared to the general population. The results were presented last week at the American Association for Cancer Research (AACR) 102nd Annual Meeting. For more information please see the AACR News website or abstract 3744 from the conference.

Risk Of HIV Transmission Can Be Predicted By Virus Levels In Genital Secretions – A study published last week indicates that the levels of HIV in genital secretions,  independently of those in the blood, indicate the risk of transmitting HIV between heterosexual partners. Participants with higher levels of virus in their genital secretions were more likely to transmit HIV, regardless of their viral load (amount of HIV in the blood). The authors stated that the results help scientists better understand when transmission risk is greatest, which could help with HIV prevention technologies and methods. For more information, please see the news article at U.S. News and World Report or the study in Science Translational Medicine (abstract).

GlaxoSmithKline Is Recruiting Participants For Clinical Trial For New Therapeutic HIV Vaccine – GlaxoSmithKline (GSK) is currently recruiting participants for a new Phase 2 clinical trial to study whether its investigational therapeutic HIV vaccine, GSK Biologicals HIV Vaccine 732462, can lower viral loads and delay the need for treatment in treatment-naïve HIV-positive adults. Therapeutic HIV vaccines are meant to help the immune system fight HIV in people who are already HIV positive. Eligible participants must have a viral load between 2,000 and 80,000 copies per milliliter of blood. The study will compare the safety and efficacy of the vaccine to a placebo. For more information, please see the U.S. Clinical Trials Registry.