WEDNESDAY, Dec. 26 (HealthDay News) -- Men undergoing hormone therapy for prostate cancer who take baby aspirin to protect their heart run a significantly higher risk of dying, new research suggests.

Apparently, baby aspirin interacts with the hormone therapy to elevate liver-function test levels. The end result is the man must stop potentially lifesaving hormone therapy.

The findings are contained in a letter published in the Dec. 27 issue of the New England Journal of Medicine.

Hormonal therapy, which involves reducing levels of male hormones called androgens, is a common treatment for prostate cancer, but it can raise the risk of a heart attack. So men who are older or have known coronary risk factors such as diabetes or smoking usually take baby aspirin while undergoing hormone therapy because aspirin helps prevent blood clots.

"Aspirin is being prescribed more widely for these men so we looked to see if there was any effect of aspirin on prostate cancer outcomes," said lead researcher Dr. Anthony V. D'Amico, chief of the division of genitourinary radiation oncology at Brigham & Women's Hospital and the Dana-Farber Cancer Institute, both in Boston.

The authors analyzed data on 206 men with localized prostate cancers who were already enrolled in a trial to compare radiation therapy alone with radiation therapy plus hormone therapy. The hormone therapy included six months of the anti-androgen flutamide.

Flutamide had a tendency to elevate results of liver-function tests. Although these elevations were benign, they meant hormonal therapy had to be stopped, at least temporarily, D'Amico explained.

Men who didn't complete six months of hormone therapy were 3.5 times more likely to die compared to men who got the full course of hormone therapy.

"It was sort of a paradoxical finding," D'Amico said. "Men who were taking aspirin were more likely to die of prostate cancer than those who were not, which didn't make sense at first."

But when the researchers delved deeper, they realized that the men who were taking aspirin were more likely to have to stop hormone therapy.

"Liver function is something you monitor" when undergoing hormone therapy, D'Amico explained. "When the tests elevate, you take the patient off of hormone therapy till the tests normalize, then you restart the therapy."

An explanation for this interaction comes from previous animal studies, D'Amico said. For rabbits that take aspirin while undergoing hormone therapy, that aspirin is magnified 100-fold in terms of how much gets into the blood. "That makes it a toxic dose of aspirin," he explained.

Although such a study can't establish a cause-and-effect association, it does appear likely, D'Amico said.

"If a man is taking baby aspirin just to prevent heart disease, we would ask the oncologist to ask the primary-care physician if he could come off the baby aspirin for the months while he's getting cancer therapy. If the aspirin is just for prevention, this is probably the simplest thing to do," he said. "But if the patient is on aspirin because he absolutely needs it, then they'd have to treat the prostate cancer without hormone therapy. It really comes down to a trade-off: How much do they need the aspirin versus how much do they need hormonal therapy, and there are alternative treatments for prostate cancer."

More information

The American Cancer Society   has more on prostate cancer and hormone therapy.

MONDAY, Dec. 3 (HealthDay News) -- Two new U.S. studies of gay and bisexual men who know they are infected with HIV show that more than one-third have recently had unprotected intercourse.

In many cases, these men are engaging in unprotected sex with other HIV-infected men -- a practice called "serosorting," where partners with a similar, HIV-positive blood test status decide to forego condoms.

However, "we also found that almost a third of the men -- 31.4 percent -- said that they had had unprotected anal intercourse with at least one partner of unknown serostatus, and almost a quarter had unprotected intercourse with a partner who they knew was HIV uninfected," said the lead author of one of the studies, Dr. Kenneth Mayer, medical research director at Fenway Community Health, in Boston.

He and other researchers in HIV/AIDS presented their findings during a teleconference Monday, part of the U.S. Centers for Disease Control and Prevention's National HIV Prevention Conference, in Atlanta.

"There are now more than one million people estimated to be living with HIV in the United States, more than ever before," said Dr. Kevin Fenton, director of the CDC's National Center for HIV/AIDS, Viral Hepatitis, STD and TB Prevention.

He also noted that half of all U.S. cases of HIV infection still occur among "men who have sex with men" (MSM), the CDC's umbrella term for gay and bisexual men, as well as men who may not identify as such but engage in male-male sexual activity.

And, Mayer added, unsafe sex was strongly linked to the use of recreational drugs, particularly methamphetamine, and was 60 percent more likely among younger men than older men.

The HIV epidemic in the United States may, in fact, be on the rise. According to recent media reports, sources close to CDC statisticians say that the annual rate of new HIV infections in the United States may soon be bumped up by 50 percent -- jumping from 40,000 new cases annually to up to 60,000.

While not confirming the statistics, Fenton told reporters that a new method for computing HIV infections is being used by the CDC. "The new estimates are not final," he said, adding that the numbers "are still undergoing rigorous analysis and scientific review to ensure the accuracy of both the new methods and of the estimates."

New statistics on rates of unprotected sex among gay and bisexual men are more certain, however. In Mayer's analysis, researchers had more than 500 Boston-area HIV-infected gay or bisexual men complete "behavioral risk assessments." Three-quarters of the men were white, with ages ranging from 21 to 70.

The research team found that 37.3 percent of the men said they had engaged in unprotected anal intercourse over the past three months. In 41.3 percent of these cases, unsafe sex took place with another HIV-infected partner, but in 31.4 percent of cases the unprotected behavior took place with a partner whose HIV status was unknown. In 23 percent of cases, the infected man engaged in unprotected sex with a partner he knew to be HIV-negative, the study found.

Another study, this one led by CDC researcher Nicole Crepaz, found similar results. Her team reviewed data from 27 studies published between 2000 and 2006. The studies included more than 10,000 gay or bisexual men who knew they were HIV-positive.

"The team found that more than a third -- or about 35 percent -- of men in the studies reported having unprotected intercourse overall," Fenton said at the news conference. Again, "serosorting" was found to be widespread, with 30 percent of the men admitting to that practice, the study found.

Black gay and bisexual men, especially, have been hit hard by HIV/AIDS, but another study showed them to be more likely to engage in safe-sex practices than their white counterparts.

In another CDC study, researchers examined data from 53 studies conducted from 1980 to 2006. The studies compared the safe-sex behaviors of black and white gay and bisexual men.

"Across all studies, there were no overall differences [by race] in reported unprotected receptive sex or any unprotected anal intercourse," said the study's lead author, Gregorio Millet, a behavioral scientist at the CDC. In fact, "among young MSM -- those ages 15 to 29 -- African-Americans were one third less likely than whites to report in engaging in unprotected anal intercourse," he said.

Black gay or bisexual men were also "36 percent less likely than whites to report having as many sex partners as white MSM," he added. Blacks in the study were also less likely to use recreational drugs, such as methamphetamine or cocaine, compared to whites.

Other studies presented at the teleconference showed close correlations between recent spikes in syphilis and gonorrhea among gay and bisexual men and rates of HIV infection in this population.

And, in a finding that puzzled experts, another study showed that circumcision -- long thought to reduce HIV infectivity -- does not help shield black or Latino men from the virus.

All of the new statistics confirm that much more must be done, the experts said.

"This shows that prevention messages have to be continually refreshed, and responsive to those who are younger," Mayer said.

More information

There's more on HIV/AIDS at the U.S. Centers for Disease Control and Prevention.

FRIDAY, Feb. 2 (HealthDay News) -- People who spend a lot of time behind the wheel may be motoring their way to an increased risk of skin cancer on the left side of their body, U.S. researchers report.

"Since previous scientific findings have shown an association between one-sided exposure to ultraviolet light (UV) and an asymmetric facial distribution of sun damage, we would expect that skin cancers also would be more prevalent on the left side of the body in drivers who spend a significant amount of time in their cars," Dr. Scott Fosko, professor and chairman of dermatology at Saint Louis University School of Medicine, said in a prepared statement.

"Our initial findings confirm that there is a correlation between more time spent driving and a higher incidence of left-side skin cancers, especially on sun-exposed areas in men," Fosko said.

He and his team looked at 898 people (559 men and 339 women) with skin cancer on either side of the body. Of the 53 percent of patients with left-side skin cancers, 64 percent were men and 36 percent were women.

The researchers also found that men, but not women, had a statistically significant number of left-side skin cancers on areas -- arms, hands, neck and head -- that are most often exposed to sunlight/UV radiation while driving.

As of January, Fosko and his team had collected 70 completed questionnaires designed to evaluate the driving habits of dermatology patients. Initial results show a direct link between driving time and left-side skin cancer risk.

The research was expected to be presented Friday at the annual meeting of the American Academy of Dermatology, in Washington, D.C.

More information

The U.S. National Cancer Institute offers advice on skin cancer prevention.