To mammogram, or not to mammogram

I’m not surprised there’s so much confusion about the new mammogram recommendations from the U.S. Preventive  Services Task Force.  The findings are counter-intuitive.  And the message is coming from data people, who can’t communicate it in a way that makes sense.

What’s more: There are a lot of people with a vested interest in the current mammogram regime.  I don’t mean to impugn their motives.  They have the best of intentions.  But, if your medical career, or your clinic, is built on the premise that all testing is good and early diagnosis is the Holy Grail, then it’s hard to be objective.  And, if you are affiliated with a non-profit advocacy group, trying to raise awareness and money to battle breast cancer, then it’s going to be hard to swallow the idea that not everyone needs to be tested.

A young woman lines up for her mammogram (at Baylor Medical Center)

This is intuitive:  Cancer starts small, and if you test for it, you might find it before it spreads and becomes lethal. If everyone gets tested, we’ll catch most cancers before they can kill.  Period.

This is not intuitive:  If we test people, and get a lot of false-positives, that causes anxiety and unnecessary biopsies.  So, it’s better to do less testing and risk a few deaths.

I’m not a specialist, and I won’t make any claims to know what all women should do.  But, the panel making the new recommendation deserves to be respected.  And their conclusion is not unprecedented.  Other researchers have been arguing for years that we do too much breast and prostate cancer screening.  European countries with the most advanced health systems do not recommend annual mammograms under the age of 50.

And as I talk to middle-aged women, I hear a lot of stories of false positives, or hard-to-read mammograms, and unhappiness with what feels like a treadmill of testing and worry. (Not to mention the mammogram procedure itself ….)

Back in the 1990’s, as CT scanning machines became more common (and less expensive),  “full body scans” became the rage.  Remember the ads?  They promised to find the diseases lurking in your body that hadn’t yet shown up in symptoms.  The medical profession roundly condemned these scans.  Why?  Because they lead to a lot of false positives, further useless testing, and possibly procedures that are unnecessary.  In the end, for most people, they do more harm then good.

If the government or medical profession is recommending that everyone should get a certain test or vaccine, then they need good evidence that the benefit outweighs the risks.

One fact we don’t like to think about:  We are all carrying around parasites and growths and abnormalities all the time.  Most of these are kept in check by natural systems.  If we tried to intervene on all of them, we’d create chaos in our bodies.

I imagine as this story evolves, we’ll see two sets of recommendations emerge–one for women with a family history of cancer (or other higher-risk status), and one for everyone else.

Pot-smoking and … testicular cancer

Ouch!  That’s not a nice association.

This was a story I couldn’t exactly pass up, because it’s a such a high-interest topic.  But, the scientists involved, and every bit of training I’ve had, warn me not to make too much of it.  (Check out the story that aired on KPLU for an overview, and here’s a press release.)

Steve Schwartz of the Fred Hutchinson Cancer Research Center has been trying to understand what causes testicular cancer.  You don’t hear much about testicular cancer (unless there’s a story about cyclist Lance Armstrong) because it’s uncommon and it’s usually curable.  But, it’s also poorly understood.  At the urging of his colleague, Janet Daling, they decided to ask if there’s any association between testicular cancer and marijuana smoking.

Based on a survey of men in the Seattle area, some with cancer, some without, they found marijuana smokers had a slightly higher risk of getting testicular cancer.  It’s newsworthy because it’s the first time anyone has shown any sort of link between marijuana and an elevated cancer risk.  The study has several limitations, so it really just points to a possibility, and the need to do more careful studies.  In general, Schwartz points out, our knowledge of the long-term effects of marijuana smoking is small.

Here are some interesting tidbits from Schwartz and the study:

  • The more often you smoke pot, the more your risk goes up.  Maybe the marijuana functions as some sort of “fuel” to keep the cancer cells growing.  When you stop, their growth stops, too.  This pattern has been shown in some types of breast and lung cancer.
  • Testicular cancer is also associated with height.  Taller men, especially those over 6 ft. 2 in., have higher rates than shorter men.
  • Men of African descent don’t tend to get testicular cancer.

It’s a cancer that seems to be triggered in adolescence, and mostly hits men between the ages of 15 and 35.

Add up that profile:  Young, white, tall man who smokes pot.  Seen any of these on a college campus?

(The paper is in the journal Cancer, and it’s called “Association of Marijuana Use and the Incidence of Testicular Germ Cell Tumors.”)