Life causes cancer. :) The symptom is cancer, the problem statement is a fix is needed for the human immune system to be more targeted and aggressive in purging cancer from the body, as well as more robust cellular repair mechanisms.
The human body can take enormous amounts of environmental abuse, but there’s clearly room for improvement.
"Approximately 39.5% of men and women will be diagnosed with cancer at some point during their lifetimes (based on 2015–2017 data)."[1]
Many lives will experience cancer, but not the majority. So it seems to be more complex that immune inadequacy (unless 60% of immune systems are working really well, which would be noteworthy). It seems like a reasonable hypothesis that environment is playing a larger role than individual genetic variations. So encouraging people (or even scaring them) to not smoke, not drink, eat better and exercise more seems like a reasonable approach - it won't cure cancer, but it could reduce rates?
Improvements should be designed to balance self preservation with self destruction. Immunotherapy, gene therapy, and CRISPR are still in their infancy.
The human body can take enormous amounts of environmental abuse, but there’s clearly room for improvement.