Marijuana smoking tied to testicular cancer: study

Tue Sep 11, 2012 5:51am EDT

A man stands in front of a medical marijuana dispensary in Los Angeles, California, July 24, 2012. REUTERS/Jonathan Alcorn

A man stands in front of a medical marijuana dispensary in Los Angeles, California, July 24, 2012.

Credit: Reuters/Jonathan Alcorn

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(Reuters) - Young men who had smoked marijuana recreationally were twice as likely to be diagnosed with testicular cancer than men who have never used marijuana, according to a U.S. study.

Researchers whose findings appeared in the journal Cancer said the link appeared to be specific to a type of tumor known as nonseminoma.

"This is the third study consistently demonstrating a greater than doubling of risk of this particularly undesirable subtype of testicular cancer among young men with marijuana use," said Victoria Cortessis of the University of Southern California, Los Angeles, who led the study.

"I myself feel like we need to take this seriously now," she added, noting that the rates of testicular cancer have been rising inexplicably over the past century.

The research isn't ironclad proof that the marijuana is to blame, and even if it is, the danger isn't overwhelming. According to the American Cancer Society, a man's lifetime risk of getting testicular cancer is about one in 270 - and because effective treatment is available, the risk of dying from the disease is just one in 5,000.

So far, little is known about what causes it. Cortessis said undescended testicles, in which the testes remain in the abdomen beyond the age of a year, are a risk factor. Both pesticide and hormone exposure have also been associated with the tumors.

Cortessis and her colleagues used data from 163 young men who had been diagnosed with testicular cancer and nearly 300 men in a comparison group without the disease. Both groups had been interviewed about their health and drug use between 1987 and 1994.

Among the men with cancer, 81 percent had used marijuana at some point, whereas that was the case for 70 percent of the comparison group.

By contrast, cocaine use was linked to a smaller risk of the tumors. That's important because it signals that men who have been diagnosed with cancer aren't just more honest about their drug use, thereby creating a spurious link between marijuana and cancer, Cortessis said.

It's not entirely clear how marijuana would influence men's cancer risk, but Cortessis said developing testicles may somehow respond to the drug's main active ingredient.

The new study is "interesting," said Carl van Walraven of the University of Ottawa in Canada, who has studied testicular cancer, but said it has a number of limitations.

For instance, it didn't find an increased risk among men with higher marijuana use, and it was relatively small.

But Cortessis highlighted the consistent results from all the studies so far.

"It is hard to imagine a scenario whereby it is due to chance and I can't think of a systematic bias that would cause this. I will feel very confident that this is cause and effect once we have worked out the biology," she said. SOURCE:

(Reporting from New York by Frederik Joelving at Reuters Health; editing by Elaine Lies)

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Comments (14)
captainkona wrote:
Every word a lie. Not even worth commenting on other than to say that this study is a farce perpetrated by the agents of misinformation.
I have smoked Marijuana for 40 years. Everyone I’ve known all my life smoke too. Never even heard of a case of Testicular Cancer amongst the reefer faithful.

Just lies. Marijuana metabolites, according to raw science, actually prevent Cancer cells from forming.

May those who commissioned and conducted this “study” rot in hell with the rest of the damned.

Sep 10, 2012 12:05am EDT  --  Report as abuse
LeroyJones wrote:
The propaganda is coming heavy now from the Pharmachutcial Industrial Complex as we approach the historic vote November 6th that will legalize Marijuana in three States. Ignore the lies and propaganda the old money empires are desperate to maintain their control. Guess what? It’s over Marijuana is coming and there is NOTHING the Federal Government or old money can do to stop it. The Pharmaceutical and Prison/Police State industry has lost. Go away and lick your wounds.

Sep 10, 2012 12:53am EDT  --  Report as abuse
bigorson wrote:
This reminds me of the study a few years ago that asserted that men who smoked pot grew man boobs.

Sep 11, 2012 1:38am EDT  --  Report as abuse
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