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Comment by melling | Hacker News Reader

According to Craig Venter, early detection is what we need to eliminate cancer:

The reason most people die from pancreatic cancer, for example, is because we almost always detect it in a late stage.

Early detection of breast cancer has had little noticeable impact on the mortality rates of breast cancer. Instead, it's been observed that the improved treatments for all forms of cancer have been the cause of a decrease in breast cancer mortality rates.

https://www.sciencedirect.com/science/article/pii/S221353831...

According to the CDC [0], the five-year net survival rate for localized pancreatic cancer is 37.4%. That's really low for an early-staged diagnosis. By comparison, early-staged colorectal cancer has an 89.9% net survival rate, despite the late-staged rate being 14.2%.

Granted, a small proportion of these cancers are caught an early stage. But I wouldn't say most people diagnosed would live five years longer if they'd caught it early. And that's ignoring lead-time bias [1].

[0] https://seer.cancer.gov/statfacts/html/pancreas.html

[1] https://en.m.wikipedia.org/wiki/Lead_time_bias

This depends on the type of cancer. In the case of a slow-growing cancer like prostate cancer, early detection can find cancers that would never be a problem (you'll die of something else first).

This has to be taken into account when deciding how much screening to do.

Not really. You’re probably still better off knowing you have the slow-growing benign prostrate cancer that you can monitor but not treat. Also, you might find you have the more aggressive form.

https://www.webmd.com/prostate-cancer/prostate-cancer-surviv...

Maybe the problem is that people don't do that? What do you think of this meta-analysis?

"Pooled data currently demonstrates no significant reduction in prostate cancer-specific and overall mortality. Harms associated with PSA-based screening and subsequent diagnostic evaluations are frequent, and moderate in severity. Overdiagnosis and overtreatment are common and are associated with treatment-related harms."

[...]

"Screening resulted in a range of harms that can be considered minor to major in severity and duration. Common minor harms from screening include bleeding, bruising and short-term anxiety. Common major harms include overdiagnosis and overtreatment, including infection, blood loss requiring transfusion, pneumonia, erectile dysfunction, and incontinence. Harms of screening included false-positive results for the PSA test and overdiagnosis (up to 50% in the ERSPC study). Adverse events associated with transrectal ultrasound (TRUS)-guided biopsies included infection, bleeding and pain."

https://www.cochrane.org/CD004720/PROSTATE_screening-for-pro...

many people also insist on getting antibiotics when they have a viral infection. We have a more measles cases now than a decade ago because of fake news.

You might be right that many people would be better off not knowing but I’d rather we took a step forwards than backwards.

Early diagnosis is much better than late diagnosis. Prevention with a healthy life style is even better.

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