For the chemo your friend likely experienced, this is especially true.

Colorectal cancer is often treated with the chemo cocktail, FOLFOX. The "OX" stands for oxaliplatin which causes nerve damage-- hearing loss (less than cisplatin, though), peripheral neuropathy, etc. The second half-life, in the body, of oxaliplatin is 535 months (44 years). And, the platinum remains in a reactive form.

I'd love to hear a professional chime in on if there are ways to speed the elimination. E.g., something like extended/extreme fasting (to free oxaliplatin from tissues) + sodium thiosulfate + blood plasma donation, or something?

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2559818/

Some choice quotes from the link:

"The first elimination half-life (t1/2) for cisplatin was 5.02 months and the second 37.0 months. For oxaliplatin, these half-lifes were 1.37 and 535 months."

"...it was shown that Pt species in pUF were still present in a reactive form."

Edit: just submitted the above article:

https://news.ycombinator.com/item?id=33154606

Good for your friend to be on the way of recovering!

Changing the title to Don't Worry About Colon Cancer Death Rates, Just Continue To Do What You're Told would not have been better or more accurate.

What would be more accurate is to say the title is incomplete. Te details matter.

If the claim was "Voluntary colonoscopy screening does not reduce the risk of death over a 10 year period" it would likely be more accurate and at least calls out the "voluntary" nature of the patients examines and the limited time span of the analysis.

No study is ever perfect and everyone has limitations. You usually learn more by investigating the limitations than poking holes in the conclusions.