Wednesday, November 26, 2008

the opposite problem


I know several women who discovered they had breast cancer much later than they ought to have, because they were refused access to screening, their doctors dismissed their concerns or their breasts were so dense that tumours were not easily detectable by ultrasound or mammogram.


And then, today I read in the Globe and Mail that a new study coming out of Norway, revealed that some cancers will disappear on their own and that more sophisticated testing, such as the MRI, can lead to "overdiagnosis":

The study, published yesterday in the journal Archives of Internal Medicine, suggested breast-cancer screening may be leading to overdiagnosis, with about 22 per cent of cases likely to resolve themselves without treatment.

Once a breast cancer is found, however, it would currently be considered unethical not to treat it. So - if the theory is correct - large numbers of women may be having surgery, radiation, chemotherapy and other treatments that would never have been needed if their cancers had not been detected.

[]Radiation can damage the heart and coronary arteries. A previous randomized controlled trial showed that about one in 10 women who receive radiation for breast cancer will die from heart damage attributable to the treatment, he said.

In a telephone interview from Oslo, Dr. Zahl said that if he and his co-authors are correct, two women die from complications of breast-cancer treatment for every woman saved by screening.

"And that's a very bad tradeoff."
The study's authors argue that, since it is considered unethical to treat cancer once it has been detected, more aggressive detection can lead to unnecessary treatment that may cause more harm than good.

I was feeling a little uneasy when I read this article and trying to articulate why, when I read a response from Dr. Amy Tuteur (thanks to Jenny for the link). Her last paragraph was the clincher for me:

Finally, and most importantly, there is no way to tell the difference on mammography, or by any other technique, between the cancers that will disappear and the ones that will go on and kill the woman. Without a practical way to separate those who need to be treated from those who do not, the finding is intriguing and worthy of further investigation, but cannot guide us in determining the best way to screen for breast cancer and the best way to treat it.
It's hard, when reading this stuff, not to consider my own situation. My breast cancer was diagnosed after I found the big, hard lump in my right breast. The kind of cancer I have is aggressive, and by the time we found it, fairly advanced. If I had had an MRI and my tumour had been discovered before the cancer had spread to my lymph nodes, the chance of metastasis could have been much lower.

How would doctors know which cancers to ignore and which to treat?

Until we have the answers to those questions, this study seems to me to be meaningless.

And I hope it doesn't used as a reason to deny tests to women who are high risk or who suspect they might have breast cancer.

Cross-posted to Mothers With Cancer.

7 comments:

Anonymous said...

Thanks, Laurie, for putting the recent research reports into perspective. I've been thinking that, perhaps, I've had unecessary treatment with more to come. But, as you've so pithily put it, how do we know (more importantly, how do the medical people know) which cancers will disappear and which will grow?

Reminds me of one of our sons who asked his step-father, a book publisher, "why don't you just publish the ones that are good sellers?" Yup!

Love,

B in T

Anonymous said...

Thanks, Laurie, for putting the recent research reports into perspective. I've been thinking that, perhaps, I've had unecessary treatment with more to come. But, as you've so pithily put it, how do we know (more importantly, how do the medical people know) which cancers will disappear and which will grow?

Reminds me of one of our sons who asked his step-father, a book publisher, "why don't you just publish the ones that are good sellers?" Yup!

Love,

B in T

Deborah said...

This report has irked me since i heard about it. I'm obviously against unnecessary treatment. But you are exactly right, how the heck do you know. And given that, wouldn't you want to try everything at your disposal (that makes sense for your situation)? The arrogance in the medical community is driving me nuts. Physicians need to listen to their patients. Recently, a friend discovered after dealing with colon cancer that it has moved to her liver and to her lungs. But SHE was the one to have to press her doctors for the tests. Outrageous.

Dee said...

Laurie,
I'm so glad that you found that rebuttal to the study because the findings of that study bothered me, too, but I couldn't articulate why.

I'm all for early screening. About five years after my first diagnosis of breast cancer, my annual mammogram found calcifications. The biopsy found a small (3mm) tumor. After the bilateral mastectomy last year, it was discovered that there was cancer throughout the whole breast - not a tumor, per se, but "tendrils" of cancer through the lymph channels and ducts. Then, about 6-8 weeks after surgery, I had a rash in that right breast area of skin that wouldn't go away. A biopsy found that there was breast cancer cells in the skin. A CT scan found small, bb-sized tumors in my bone marrow in my spine, ribs, iliac, sacrum, etc. That's when I started oral chemotherapy. I asked my onc how long those little bb-sized tumors had been there and his reply was "months".

IF I hadn't had the mammogram that showed calcifications and IF the biopsy hadn't found the little 3mm tumor, and IF I hadn't been vigilant about the skin rash, the cancer would've grown and spread to other organs. I think that I'm doing really well, with low tumor markers and stable disease, precisely because of early screening. The cancer hasn't had a chance to get into my bones - it's only in my bone marrow. We caught it fairly early, in other words, and it was aggressive. I think I've been spared really more aggressive treatments with worse side effects because of early detection.

A year later, I'm doing well - I'm happy, back at work, and starting to prepare myself for reconstruction surgery in February.

I agree - that study is meaningless, for now, and will be until they can say which cancers will go away and which will kill someone.

You know, I'm going to put a link to your blog entry along with my reply . . .

Deborah said...

interesting post , thank you for bringing that research to our attention.

Rebecca said...

Laurie, I saw this on one of the big national network morning tv programs. They brought up the point that there was a lot of MISSING factors in the study. Like what were the pre-existing risk factors? Since cancer can happen to anyone, how does one create a study to show that cancer goes away? And the women who didn't have any screening at all, how do we know they had cancer that went away?

The study's conclusion was seriously flawed and miss leading. I just wonder how many young women will hear about it and not push to be screened?

Patty said...

In my case I had a mammogram and 6 months later I had Stage III breast cancer. My surgeon reviewed the mammogram and said there is absolutely no tumor visable. Really scary stuff. I found the tumor through self exam about 3 months after my mother's death. No doubt she is still watching over me. Treatment about to start.