An Australian study that reviewed the lifetime risk of 5 cancers came up with a conclusion that is pretty controversial.
This study suggested that roughly 24 % of all cancer diagnoses in men are what you would call “over-diagnosed” while 18 % of caners in women fall into the same category, at least according to these researchers.
What do they mean by “over-diagnosis?”
It’s not that the diagnosis of particular cancers was wrong.
Rather, it’s that those particular cancers were not producing symptoms and if left alone, those malignancies would not have gone on to cause harm to those patients.
How did these cancer over-diagnoses break down?
According to this study, the over-diagnosis category included an amazingly-high 73 % of all thyroid cancers in both men and women, while in men alone it included 42 % of prostate cancers, 42 % of kidney cancers, and 58 % of melanomas, and in women alone, these researchers claim that 22 % of breast cancers, 58 % of kidney cancers, and 54 % of melanomas were over-diagnosed.
Do these numbers apply in Canada?
Probably not exactly (we have, for example, much lower rates of melanomas in cold, wet, wintry Canada than they do in sun-drenched, too-hot Australia) but probably pretty similarly for the other cancers.
Why this huge spike in over-diagnoses over the last 3 decades?
A couple of reasons stand out: Much better methods of cancer detection that pick up very tiny changes long before they can cause any problems, and for certain cancers, a broader definition of what makes up that type of cancer.
Anyway, the bottom line is the same: If you are ever diagnosed with any cancer but especially these mentioned in this study, always, always, always ask if, given your age and state of health, that’s a cancer that is likely to go on to cause you harm.
You might be happily surprised to find out that that cancer really won’t affect your life.