MONDAY, Feb. 1 (HealthDay News) -- Men with prostate cancer and the physicians who treat them are being warned that the androgen-deprivation therapy (ADT) commonly used against the malignancy might increase the risk of heart attack and cardiac death.

"There is a substantial amount of data demonstrating that ADT adversely affects traditional cardiovascular risk factors, including serum lipoproteins, insulin sensitivity and obesity," according to an advisory published online Feb. 1 in Circulation by a group of experts from the American Heart Association, American Cancer Society and the American Urological Association.

The warning is guarded, saying that risks have not been found in all studies. "But we think that physicians treating patients with localized and metastatic prostate cancers as well as patients ought to realize that there are significant risks associated with the use of hormone therapy," said Dr. Otis Brawley, chief medical officer of the American Cancer Society.

ADT reduces or eliminates the male hormones that can promote growth of prostate cancer. About one-third of all men with prostate cancer are given ADT, Brawley noted.

"Many people underestimate the harm of hormonal therapy and overestimate the potential benefits of hormonal therapy," he said.

Six studies -- two done in Europe, four in the United States -- have shown increased incidence of cardiovascular problems in men, Brawley said.

One U.S. study of 37,000 men treated for prostate cancer at Veterans Affairs hospitals found a 27 percent increased risk for heart disease among those given multiple hormone-blocking agents. Surgical removal of the testes was associated with a 40 percent increased risk for heart disease and a more than doubled risk for a heart attack.

"These drugs do have usefulness," Brawley said. But there has been debate about whether ADT should be used in some cases, such as when levels of prostate-specific antigen (PSA), a cancer-associated protein, begin to go up but there are no other signs and symptoms of cancer progression, he said.

"A man has had radical prostatectomy [cancer surgery] and PSA starts rising again," Brawley said. "There has been a debate in the medical profession: Should we start hormonal therapy or just watch it go up and act only if we see the cancer spreading?"

More research is needed to determine the proper course of action in these and other cases where the course of the disease is not clear, the new advisory said.

Meanwhile, "the American Cancer Society is advising that physicians be aware that all hormone therapies for prostate cancer can have an increased risk of cardiovascular disease and diabetes and death," Brawley said. "They can be useful in treatment but should be used with caution."

A need for caution was also emphasized by Dr. Arthur Sagalowsky, a professor of urology and chief of urologic oncology at the University of Texas Southwestern Medical Center in Dallas and one of two urologists representing the American Urological Association on the panel that produced the advisory.

"One needs to be very careful in not overdrawing conclusions beyond what the panel has done," Sagalowsky said.

The risk for cardiac problems should be one of many issues discussed in the treatment of prostate cancer, he said. "It adds to the body of information that I present to patients with prostate cancer when they decide whether or if to begin androgen-deprivation therapy," he said. "How one decides will depend on the circumstances of the patient's prostate cancer, and this individual side effect is one of the issues that enter into the discussion."

More information

The U.S. National Cancer Institute has more on prostate cancer.

MONDAY, Nov. 9 (HealthDay News) -- Researchers were able to restore sexual function to rabbits with damaged penises by growing new penile tissue in the lab and implanting it, a new study reports.

Though a human application is a ways off, researchers say the technique could one day be used to treat severe erectile dysfunction in men.

"We were able to show the tissue was able to integrate and function in the long term, which means we can start planning clinical applications [in humans]," said Dr. Anthony Atala, director of the Institute for Regenerative Medicine at Wake Forest University Baptist Medical Center and senior author of the study. "Our hope is to be able to treat patients with many conditions, including congenital abnormalities of the penis, traumatic injuries, penile cancer and severe cases of erectile dysfunction that don't benefit from drug treatments."

The study is published in the Nov. 9 online edition of the Proceedings of the National Academy of Sciences.

The penis is a complex organ, with nerve, muscle and vascular cells all needing to work together to achieve and maintain an erection. During an erection, smooth muscle tissue relaxes, allowing blood to flow into the penis. Endothelial cells, which line blood vessels, trigger the process by releasing nitric oxide.

In the study, the researchers extracted smooth muscle cells and endothelial cells from the animals' penises. The cells were then separated and grown in the laboratory on rod-shaped collagen scaffolds for support. The scaffold was placed in an incubator and nourished by fluids to mimic conditions inside the body, Atala said.

After the cells had matured, the scaffolding and the newly formed penile spongy tissue, called corpora cavernosa, was surgically implanted into the rabbits' penises.

About a month later, the tissue began to reconstitute itself, forming new blood vessel structures necessary for proper functioning, while nerves from the existing penile tissue integrated into the new tissue. In time, Atala said, the collagen structure was reabsorbed, and the cells built their own collagen structure.

In the treated rabbits, tests showed that pressure inside the penis, a key component of an erection, was normal. Other tests showed that blood flow, response to nitric oxide, drainage of the blood after the erection and presence of sperm in the female vagina were also normal. The tissue engineering worked so well that four of 12 females were impregnated by the repaired rabbits, according to the study.

Dr. Andrew McCullough, director of male sexual health, fertility and microsurgery at NYU Langone Medical Center, said the results are promising.

"It has a long way to go, but the researchers have basically shown they can take cells from an organ, culture them, put them back in and have them be functional," McCullough said. "This is especially impressive because the penis is an organ that's a very sensitive hydraulic pump, so to speak. During an erection, blood has to flow into the organ. The organ then has to expand and then shut down the drainage so the blood doesn't flow back out. And all of these things are very interrelated."

Better treatments for erectile dysfunction are badly needed, McCullough added. About 35 percent of men don't respond to impotence drugs, including Viagra, Cialis and Levitra. As men age, diabetes, high cholesterol and hypertension -- all conditions that can affect male sexual function -- can worsen, making the drugs less effective.

In previous research, the Wake Forest researchers engineered human bladders in the lab. In clinical trials, about 30 children and adults with congenital bladder abnormalities or bladder injuries who were treated with the engineered tissue showed normal or improved bladder function for nearly 10 years, Atala said. Other researchers have shown some success in clinical trials with transplanting windpipe tissue.

More information

The Cleveland Clinic Foundation has more on penile disorders  .