Articles, Blog

Overtreatment of Stage 0 Breast Cancer DCIS

August 31, 2019

[Music] the whole point of cancer screening is to detect life-threatening disease at an earlier more curable stage so an effective cancer screening program would therefore increase the incidence of cancer detected at an early stage because you’d find all those tiny cancers you would have missed before and therefore decrease the incidence of cancer preventing at a late stage because you would have cut out all the little cancers you found pulling them out of circulation but that’s not what appeared to happen with mammograms and as mammography ramped up in the 80s the first part happened that diagnosis of early cancer shot up and so what we’d like to see is like a mirror image of this going the other way for late stage cancers have you caught it early it wouldn’t be around for late but that didn’t happen late stage cancer incidence didn’t seem to drop much at all another way to look at this is to compare mammogram rates around the country the more mammograms you do the more heavily screen the population is the more early cancers you pick up great and late advanced disease should go down too right but it doesn’t we’re taking all these early cancers out of circulation surgery radiation so there should be about the same number of fewer late stage cancers found but that didn’t happen mammograms catch a lot of small cancers but with no comment decline in the detection of larger cancers that would explain this the more mammograms you do the more cancer you find but death from breast cancer doesn’t seem to change much wait a second you just cut out tens of thousands of cancers why aren’t there are that many fewer women dying together these findings suggest widespread over diagnosis meaning cancer picked up on mammogram that would have never progressed to the point of presenting during the woman’s lifetime and so wouldn’t even have been noticed or caused any harm had it never been picked up at all so from moving all these early ones didn’t lead to that many fewer late ones that suggest that most would have never progressed during that time or even go away on their own that could explain almost all that increase in incidence and indeed many invasive breast cancer detected by repeated mammography screening do not persist to be detected later suggesting that the natural course of many of the mammograms detected invasive breast cancers is to spontaneously regress spontaneously disappear we’ve known for more than a century they’ve even serious metastatic breast cancer can sometimes just spontaneously go away the problem is that you can’t tell wishes which so if you find it the natural inclination is to treat it which can be especially tricky for ductal carcinoma in situ DCIS so called stage zero breast cancer this is what it looks like ductal means in the breast ducts carcinoma means cancer and in situ means in place in position not spreading outside the duct and I can create these tiny calcifications that can be picked up on mammogram the whole point of mammograms was to identify early invasive disease so the large numbers of DCAA yes they found were unexpected unwelcome prior to the advent of mammogram screening das made up approximately 3% of breast cancers detected but now accounts for a significant chunk the cells look like invasive cancer and therefore the presumption was made that these lesions were the precursors of cancer stage zero cancer and that early removal and treatment would reduce cancer incidence in mortality however long-term population studies have demonstrated that the surgical removal of 50,000 to 60,000 DCIS lesions annually has not been accompanied by a reduction in the incidence of invasive breast cancers this is in contrast to our experience with removing colon polyps with colonoscopy or precancerous cervical lesions thanks to pap smears in which the removal of precursor lesions has led to a decrease in the incidence of colon and cervical cancer those are cancer screening programs that work radiologists argue that over diagnosis is so much the problem has over treatment yeah it sucks to get a breast cancer diagnosis even though it would never hurt you but you don’t know that at the time so most women undergo aggressive surgical and radiation treatment yeah but if you compare the ten-year breast cancer survival for women with low grade DCIS among those who chose not to go to surgery at all 1.2 percent of them died of breast cancer within a decade but in that same decade those that went to surgery instead for a lumpectomy or a full mastectomy to cut it out 1.4 percent died from breast cancer so surgery appeared to make no difference that’s why they’re currently randomized control trials to put it to the test but it’s incredibly difficult to convince a patient with DCIS not to just want to get it cut out the fear of cancer paralyzes patients who may resort to drastic excessive measures like getting a double mastectomy how can we prevent that how about we change its name a National Cancer Institute panel is recommended dropping the carcinoma part let’s just call it an indolent lesion of epithelial origin they use language that engenders less fear how bad can an idyll tumor be another option to avoid this dilemma is just not get screened in the first place but women aren’t typically told about any of this lesson one in ten women were aware of that mammograms carried any potential arms at all and more than nine out of ten were unaware that some breast cancers never cause problems few were told about D serious but when informed about it most wished they were told before they signed up once a cancer is detected it’s currently not possible to distinguish life-threatening from potentially harmless cases therefore over diagnosis can only be avoided by abstaining from routine mammograms altogether and that’s how this researcher explained her own decision away from screening worried by the possibility that she could be seriously harmed by the treatment of a cancer that would have never affected her health and given that the only way to avoid opening that Pandora’s box is by not getting mammograms instead she decided to try improving her diet and lifestyle getting breast cancer in the first place [Music] you

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