Recently YouTube again started recommending to me channels of people who died of cancer.
I looked at a clip of a man just a few years my senior where he was describing the symptoms that in his view should have made him go see a doctor earlier, because maybe then his pancreatic cancer wouldn't have been fatal.
Truth be told they wouldn't raise any red flags if I had them.
Only thing that I'm doing differently is having blood tests done on an annual basis, but those only show anything when e.g. the cancer has spread to the liver, which is typically too late anyway. It's an incredibly insidious disease, and if the tumor is growing on the wrong end of the organ, it won't give any symptoms whatsoever.
That is the problem with symptoms in general. Most people who go to the hospital with "chest pain" are not having a heart attack - but it is still the best symptom we have and so emergency rooms "waste" a lot of time one people who have nothing wrong. Or more likely they just have a mild constipation case (look up constipation, and then look up the individual symptoms - most of them are also symptoms of GET TO THE ER NOW type things)