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I really appreciate @Medscape writing about our NEJM article on melanoma screening. https://www.medscape.com/viewarticle/944105
Let me briefly address some of the counterarguments to our article. They're fair but actually support us. To say that MIS treatment "does more harm than good" is not to say it doesn't do good. This quote is a roundabout way to say the same thing - our only method is to overtreat.
We are clear that UV radiation is the most consistent melanoma risk factor. To say a risk factor is "weak" is not to say it's not real (the opposite!). An RR of 2 means your chance is doubled! That's real. And being modifiable also doesn't make it epidemiologically stronger.
The pathologic threshold study we cite is not conclusive. But let's not lose the forest for the trees here. There is no epidemiologic evidence of benefit and proponents haven't run conclusive RCTs for their position either. They have no more evidence than we do, less actually.
Who can counter this? Anyone who has gone to med school in the last decade should be familiar with the terms lead time bias and length time bias. It's literally medical gospel that you shouldn't use stage at diagnosis as a surrogate for benefit. And yet experts still do this.
We wrote an academic article targeted to doctors. I hope to have a high level of discussion about a complex, unsolved issue. Look carefully at the words both sides use.
"Weak" risk factors are real risk factors. No one has countered that the RR is greater than 2.
"Weak" risk factors are real risk factors. No one has countered that the RR is greater than 2.
The fundamental issue with overdiagnosis is that some people will be helped - even have their life saved. But how many will not be helped?
This isn't a pro-con thing. Overdiagnosis doesn't go away because you like the benefits. It's about balance of benefits and harms.
This isn't a pro-con thing. Overdiagnosis doesn't go away because you like the benefits. It's about balance of benefits and harms.
There is only one way to totally remove overdiagnosis from medicine: make doctors clairvoyant. But since we can never fully predict the course of an untreated illness and what competing causes of death an individual might face, we are left with imprecision.
Consider a thought experiment: say the population mortality of melanoma were declining over decades. Would dermatologists be trumpeting this as proof of benefit? Urologists and gastroenterologists certainly do for prostate and colon ca.
So is it crazy to suggest the alternative?
So is it crazy to suggest the alternative?
A mea culpa about MIS though. We could have been more clear in explaining that even if many invasive melanomas arise from MIS, the issue is that most MIS does not turn into invasive melanoma.
Most colon cancers arise from polyps/adenomas, but most polyps don’t become cancer.
Most colon cancers arise from polyps/adenomas, but most polyps don’t become cancer.
