Breast self-exams are not useful

[Monique]

Breast self-exams are not useful, they can do more harm than good. That is the conclusion of the Cochrane Center.

http://mrw.interscience.wiley.com/cochrane/clsysrev/articles/CD003373/frame.html

The conclusions reach so far in that the Dutch Cancer Foundation is stopping all recommendations for self-exams, they will stop educating women on the technique and actually start a campaign explaining the downside of self-control (the unnecessary photos, biopties, scars, infection risk).

 

[lisab]

Several years ago, a similar (but much smaller) study was released here in the US. But my physician told me to ignore it, and that his own mother discovered a tumor during a self-exam.

My mother and aunt have had breast cancer...I'm in a high-risk population. Even though I understand the risks involved in biopsies, I think I'll keep doing self-exams.

 

[Monique]

I think it is good that you think that way, it is always important to catch things early. I don't think they will be discouraging people to perform self-exams, but they won't be promoting it anymore either.

 

[Mk]

I think the uncensored videos on YouTube of an instructor teaching breast examination are still going to be among the most-watched.

 

[Evo]

I think it is good that you think that way, it is always important to catch things early. I don't think they will be discouraging people to perform self-exams, but they won't be promoting it anymore either.

It doesn't seem that they are recommending anything instead like yearly mammagrams.

 

[Dale]

Thanks for showing this excellent study. I am often dismayed by how rarely these kinds of studies are done. Any diagnostic test has some risk, even if it is subtle as in the case of breast self-examination. When applying the test broadly across a large healthy population the risk can easily outweigh the benefit. Until studies like this are performed I am generally skeptical of the real value of any screening of healthy populations without clear risk factors.

 

[Evo]

Several years ago, a similar (but much smaller) study was released here in the US. But my physician told me to ignore it, and that his own mother discovered a tumor during a self-exam.

My mother and aunt have had breast cancer...I'm in a high-risk population. Even though I understand the risks involved in biopsies, I think I'll keep doing self-exams.

Yes, I know a number of women that found breast cancer through self exams.

 

[Lisa!]

I heard that mammography could increase the risk of cancer, is that right?

 

[Dale]

Mammograms use ionizing radiation, so yes. But the amount of radiation is very small, so the risk of cancer is also small. I suspect that follow-up procedures due to false positives are a greater risk than the radiation exposure.

 

[turbo]

This is a hot topic in our household. I lost a school-mate to breast cancer a little over a year ago, and my wife lost a very dear friend to the disease earlier this year. In addition, we have a more recent acquaintance that is dealing with it, and we're hoping for an all-clear. My wife's employer (New Balance Athletic Shoe Co) is very pro-active about breast cancer and sponsors events to raise awareness and raise money for research. I don't think many of the women in our circle of friends will abandon self-examination, but neither will they place a great reliance on it. It's just one more screening option.

 

[Monique]

When applying the test broadly across a large healthy population the risk can easily outweigh the benefit.

Certainly, I think a distinction should be made for people with and without a family history. It is good to inform people about the risks of a particular procedure, I think it is commonly underestimated.

 

[Dale]

Certainly, I think a distinction should be made for people with and without a family history.

Definitely, any known risk factor, including family history, changes the balance between risk and benefit.

 

[Moonbear]

It seems that's a premature response to this review to stop recommending breast exams. The review mentions several ongoing studies, but in the end, bases its conclusions on two, one Russian study, and one from Shanghai. The Russian study found a benefit in detecting more cancers when women were taught breast self-exam, while the Shanghai study did not.

It seems to me that before changes in policies are implemented regarding recommendations for self-exam, the reasons why the two studies differed in outcome needs to be explored. For example, breast self-exam only can account for detection of "lumps." Perhaps the failure has nothing to do with success in detecting those lumps, but in the follow-up care that determines whether a biopsy is performed on those lumps. The issue doesn't seem to be early detection, but the rate of biopsy. Once a woman detects a lump and goes to her doctor, it is then up to the doctor to determine if a biopsy is indicated. Are the lumps being found during early exams, or after a long period of negative exams for comparison? Are they followed for a while to see if they are changing, or are they immediately biopsied? A lot of factors can change whether unnecessary biopsies are being done, and that isn't necessarily a flaw in breast self-exam, but in how the physicians address concerns when a patient finds a lump.

I would also think that risk factors need to consider the type of biopsy...is a needle biopsy performed, or is it a surgical removal of the mass? The potential risk to the patient is different with each. Once a lump is found, what about the patient's peace of mind? Is it better to undergo a minor surgical procedure and be reassured all is benign, or do nothing and have the patient worried they really might have cancer and the doctor isn't listening to their concerns?

 

[Ivan Seeking]

Mammograms use ionizing radiation, so yes. But the amount of radiation is very small, so the risk of cancer is also small. I suspect that follow-up procedures due to false positives are a greater risk than the radiation exposure.

However, isn't it true that mammography is done with low KV, which makes it more likely to produce destructive interactions than are other types of studies that result in similar levels of exposure to radiation?

 

[Dale]

Mammography does use lower energy than CT (28 kV vs 120 kV), but even accounting for the higher activity the dose equivalent is still much smaller (3 mSv vs 20 mSv). Dose equivalent is the measure of the biological effect of radiation exposure, factoring in the physical dose, type of radiation, and sensitivity of the tissue.

However, 3 mSv is also the same as the annual background dose equivalent for most people, so it is not a negligible amount of radiation in the context of regular screening of healthy individuals with no risk factors.

 

[CRGreathouse]

However, 3 mSv is also the same as the annual background dose equivalent for most people, so it is not a negligible amount of radiation in the context of regular screening of healthy individuals with no risk factors.

So assuming (arbitrarily) that half the cancer risk in the non-mammogram population can be attributed to radiation, the linear no-threshold model would predict a 50% increases in the cancer incidences worldwide from no mammograms to yearly mammograms for all. That would be around 700,000 additional cases each year. A more sensible model, in which low doses of radiation are less likely to contribute to cancer (say, a positive derivative for risk of death wrt exposure) would predict yet more deaths. Depending on how risk for cancer accumulates over one's life, screening only older women could cut this down by as much as perhaps half.

Of course an increase in the number of cancer cases might be worthwhile if enough are caught early on. But this analysis doesn't include the cost of the mammograms, which I don't know. It's possible that while decreasing cancer deaths the cost of the additional screenings and treatment for the cancer that is found early (including that caused by the screening) could be better used to improve other aspects of health.

Any takers on this line of thought? Before critics rip me apart, let me list my biases:

• I'm a man (about 100 times less likely to get breast cancer than a woman)
• I've lost 2/4 grandparents and 0/2 parents to cancer (not breast)
• I was diagnosed with breast cancer a few years ago (a second opinion said it wasn't; the second opinion was right)
• I'm professionally involved with radiation safety