Merged Breast cancer screening 'damaging women'

[sleepy_lioness]

http://www.guardian.co.uk/society/2012/oct/30/breast-cancer-screenings-damaging-women

Apparently for every life breast screening saves, three women are treated (with radiotherapy, chemotherapy, surgery) for a cancer that would never have harmed them. But there's no way to know whose cancer will kill them and whose will grow so slowly that it'll do no harm.

Thoughts? I'm too young to be caught by my country's screening programme, and I just hope they sort it out by the time I'm there! I think I'd still go for screening, however, but I'm really not sure.

 

[Aepervius]

There is a similar problem with PSA screening (prostate cancer). And i am starting in the next days.

I would be really interrested into reading the answers of others.

 

[LarianLeQuella]

I think the missing part of the puzzle is getting a second opinion, and doing a proper analysis of screening results. As soon as someone hears the big C-word, they freak out and demand treatment, even though it may not be totally warranted.

That of course is my layman opinion.

 

[sleepy_lioness]

I'd thought that as well (and am equally lay!), but apparently the scans will correctly show small cancers, and nobody (not a first, second or any subsequent) opinion can tell whether these cancers will become the quickly fatal type, or whether they will grow so slowly that the woman will die from something else long before the cancer would have become an issue.

And yes, it's my understanding too that the same is true for PSA testing for prostate cancer.

 

[LarianLeQuella]

and nobody (not a first, second or any subsequent) opinion can tell whether these cancers will become the quickly fatal type, or whether they will grow so slowly that the woman will die from something else long before the cancer would have become an issue.

Again, a layperson that doesn't even pretend to be a doctor in any sense (even in RPGs); isn't that what a biopsy is for? Given the advances in being able to perform minnimally invasive biopsies, wouldn't that help in making that determination?

Where's an actual doctor when talking about this stuff?!

 

[Jorghnassen]

Ah, that's a tough one now is it? In medical science, they call it specificity and sensitivity... It's the good old radar problem: make it too sensitive, and you'll scramble the RAF for a flock of birds (and that'll cost you, because resources are limited), make it too specific and you won't scramble the RAF until the entire Luftwaffe is already over London, bombing it back into the stone age.

As a statistician, all I can say is that perhaps, research and population healthwise, they should focus the new resources more on treatment than public awareness and detection (unless the latter is to tell apart the types of cancer, rather than cancer vs no cancer). But, for that, mentalities need to change a bit. It may be the case that some cancers are better left untreated, just monitored. The "earlier detected, better survival" mantra may need to be nuanced a bit (slow evolving cancers are less of a problem, agressive ones may be just too difficult to detect early on, at least with mammograms). And perhaps guidelines need more variety than a "one-size fits all" mentality as well. Perhaps it's time to make the C-word a little bit less scary than it is in the public opinion.

 

[sleepy_lioness]

Thanks, Jorghnassen. Interestingly, the news stories reporting this say that the British NHS is going to change the advice leaflets they send to women asking them to report for screening, as a result of the research. Presumably it'll highlight the greater-than-thought risks of overdiagnosis. How they expect women to make a decision I don't know, however, (I'm a reasonably intelligent woman and I really don't know what I'd do).

 

[ChumpusRex]

Again, a layperson that doesn't even pretend to be a doctor in any sense (even in RPGs); isn't that what a biopsy is for? Given the advances in being able to perform minnimally invasive biopsies, wouldn't that help in making that determination?

Even biopsy does not have 100% specificity (i.e. no false posisitives) and 100% sensitivity (i.e. no false negatives). Biopsy is frequently considered a "gold standard", but sometimes a medical decision has to be made to go against a biopsy until after potentially definitive treatment.

Breast screening picks up a lot of very small and very subtle abnormalities. Not all are amenable to biopsy, or are sufficiently small that if biopsied, the biospy may be negative, but significant medical concern remains.

In a lot of cases, surgery is the result. Sometimes the definitive pathology is positive for cancer, sometimes it is not. This fact, in itself, is perhaps a bit of a digression from the point of the article.

The issue raised in this article is that even if the biopsy is positive, or the surgical specimen positive for cancer, is/was treatment appropriate? The answer is not necessarily, the impulsive "yes".

Cancer is a variable disease. Some cancers are aggressive, others are indolent and cause little harm, or cause harm only very slowly. While the natural history of large cancerous tumours is well established in most organs, in that large tumours with evidence of tissue invasion tend to kill very quickly, is reasonably well established. The same is not true in smaller tumours. Do small cancers become big cancers? Big cancers, presumably, must have been small cancers at some point; so the answer must be that at least some do. How many do, how quickly they do so, and whether some might spontaneously regress has not been clear. The traditional approach has been to regard a cancer as a cancer, and that it needs to be treated.

The point of this article comes from a recent analysis of data from the breast screening programme which is that the screening programme diagnosed 20% more cancers in the women it screened, than are diagnosed in an equivalent population of women that were not screened. The conclusion from this finding is that in unscreened women, approximately 20% will never have their breast cancer diagnosed (presumably because they never get symptoms of their cancer).

 

[Roma]

This confusion is exactly why I haven't had a mammogram yet.

 

[sleepy_lioness]

The point of this article comes from a recent analysis of data from the breast screening programme which is that the screening programme diagnosed 20% more cancers in the women it screened, than are diagnosed in an equivalent population of women that were not screened. The conclusion from this finding is that in unscreened women, approximately 20% will never have their breast cancer diagnosed (presumably because they never get symptoms of their cancer).

Thanks. So is the figure of 3 unnecessary treatments for every life saved extrapolated from the idea that, not only would 20% never have known they had breast cancer, but many others would have known they had it but it would never have killed them?

 

[Professor Yaffle]

A good article on the subject by GP Margaret McCartney:

http://www.guardian.co.uk/commentisfree/2012/oct/31/breast-screening-paternalistic-wrong?CMP=twt_gu

 

[EHocking]

http://www.guardian.co.uk/society/2012/oct/30/breast-cancer-screenings-damaging-women

Apparently for every life breast screening saves, three women are treated (with radiotherapy, chemotherapy, surgery) for a cancer that would never have harmed them. But there's no way to know whose cancer will kill them and whose will grow so slowly that it'll do no harm.

Thoughts? I'm too young to be caught by my country's screening programme, and I just hope they sort it out by the time I'm there! I think I'd still go for screening, however, but I'm really not sure.

See also this thread, Breast screening "creates cancer patients"?

 

[keyfeatures]

I'm currently having chemo for primary breast cancer. The cancer wasn't found by a mammogram but by self-check confirmed by biopsy. In fact, the mammogram didn't show any lump / cancer as my breasts are very dense (which is quite common in younger women who haven't had children). I also had an MRI which gave a false positive of further lumps that proved not to be cancerous on biopsy. As my radiographer said, these screenings just give indicators. You can only really know if there is a cancer there by taking a biopsy and looking at the cells.

Something I've learned since diagnosis is that when it comes to cancer, the medical professionals are having to use imperfect diagnostic tools and treatments. They do the best they can with the best we have. It's a case of probabilities and weighing up risks against benefits. Our bodies are all creating cancerous cells all the time, but usually the immune system deals with them. We still don't know for sure why sometimes our bodies fail to deal with them, although there are risk factors such as having certain genes or smoking.

My cancer may all be gone but the probabilities that there is some micro met lurking mean it's recommended I have chemo, radiotherapy, hormone treatment and herceptin. These all come with serious risks and unwelcome side effects. This is the reality cancer patients and those treating them are dealing with every day.

Personally, I'd like to see screening programmes extended to younger women as whilst we are less likely to get the disease, those of us that do have longer ahead for any cancer to develop. We are also more likely to die from the disease. No one is certain why this is, but later diagnosis and active hormones are suspected. I'd favour manual check by trained professional and ultrasound over mammogram.

 

[keyfeatures]

Again, a layperson that doesn't even pretend to be a doctor in any sense (even in RPGs); isn't that what a biopsy is for? Given the advances in being able to perform minnimally invasive biopsies, wouldn't that help in making that determination?

Where's an actual doctor when talking about this stuff?!

No, a biopsy can't tell you this. A fine needle biopsy will only tell you if there are cancer cells there and a core biopsy will only tell you how that core of cells is lying within the breast (e.g. if it is invasive or in situ). It won't be able to tell you how far the margins of the cancer extend or the nature of the entire tumour. It also won't tell you if there is any lymph involvement or vascular invasion.

 

[TubbaBlubba]

A year or so ago I talked to an MD and PhD in immunology and... endocrinology, I think, (nothing directly relevant) about this. According to her, the big problem was self-screening, which isn't that good and gives a false sense of security.

 

[Skeptic Ginger]

All medical decisions are risk vs benefit. This is no different. The risks of false positive mammograms are nothing new, this is just another quantification of it.

A while back mammogram recommendations changed to start later unless a woman had certain risk factors.

With more data researchers can look at which results should simply be observed and which should be treated. I think the news article might be misstating the description of "treatment". The vast majority of the time a false positive merely results in an unnecessary biopsy. Cancer is not treated on the basis of an X-ray unless it's a recurrence. Rather, an X-ray is one step and specific identification is then done with a biopsy.

 

[Skeptic Ginger]

No, a biopsy can't tell you this. A fine needle biopsy will only tell you if there are cancer cells there and a core biopsy will only tell you how that core of cells is lying within the breast (e.g. if it is invasive or in situ). It won't be able to tell you how far the margins of the cancer extend or the nature of the entire tumour. It also won't tell you if there is any lymph involvement or vascular invasion.

Some biopsies are definitive. It depends on the type and location of the tumor. It's one reason why wide margins are often used and the pathologist can see if the tumor extends. (The other reason is so cancer cells aren't released into the body where they can act as seeds.)

 

[Skeptic Ginger]

I'm currently having chemo for primary breast cancer. The cancer wasn't found by a mammogram but by self-check confirmed by biopsy. In fact, the mammogram didn't show any lump / cancer as my breasts are very dense (which is quite common in younger women who haven't had children). I also had an MRI which gave a false positive of further lumps that proved not to be cancerous on biopsy. As my radiographer said, these screenings just give indicators. You can only really know if there is a cancer there by taking a biopsy and looking at the cells.

Something I've learned since diagnosis is that when it comes to cancer, the medical professionals are having to use imperfect diagnostic tools and treatments. They do the best they can with the best we have. It's a case of probabilities and weighing up risks against benefits. Our bodies are all creating cancerous cells all the time, but usually the immune system deals with them. We still don't know for sure why sometimes our bodies fail to deal with them, although there are risk factors such as having certain genes or smoking.

My cancer may all be gone but the probabilities that there is some micro met lurking mean it's recommended I have chemo, radiotherapy, hormone treatment and herceptin. These all come with serious risks and unwelcome side effects. This is the reality cancer patients and those treating them are dealing with every day.

Personally, I'd like to see screening programmes extended to younger women as whilst we are less likely to get the disease, those of us that do have longer ahead for any cancer to develop. We are also more likely to die from the disease. No one is certain why this is, but later diagnosis and active hormones are suspected. I'd favour manual check by trained professional and ultrasound over mammogram.

I'm glad you are OK. I see no reason not to use both self exams and mammograms when recommended.

The newer digital mammograms use less radiation and provide a better image. OTOH, there can then be more false positives. I'd rather have a false positive than miss a real one.

 

[Skeptic Ginger]

This confusion is exactly why I haven't had a mammogram yet.

Have the mammogram if it is recommended for your circumstances (age and risk factors). Don't go by news stories that poorly explain research results.

 

[KatieG]

I have breast cancer stretching back way down both sides of my family. I've been getting a mammogram every year for the last 19 years. Less stressful having one after my breast reduction and also somewhat easier to detect.

I tire of the medical world changing their minds every few years and claiming that something that was good or bad for you is now the opposite. I try to eat well, exercise as much as possible and take good care of myself. I appreciate having these kinds of tools available.