Cancer death rates are falling, five-year survival rates rising

In first world countries, death is caused by very roughly 1/3 heart diseases, 1/3 cancer, 1/3 others. More heart diseases mean less cancer and vice versa.

5 year survival may be a good metric though.

At the end he wished he had never been diagnosed, then he probably would have had a decent half year or so.

It is generally helpful to track statistics by stage, but stage is just one of MANY factors.

We can, however, compensate for lead-time bias by tracking survival based upon the stage of the cancer (a measure of how advanced the cancer is)

https://sciencebasedmedicine.org/the-early-detection-of-canc...

Excerpt:

This earlier detection can also lead to an overestimation of the efficacy of treatment. That’s the grain of truth in the comment above. The reasons for this are two types of bias in treatment studies known as lead time bias and length bias. In the case of cancer, survival is measured from the time of diagnosis. Consequently, if the tumor is diagnosed at an earlier time in its course through the use of a new advanced screening detection test, the patient’s survival will appear to be longer, even if earlier detection has no real effect on the overall length of survival, as illustrated below:...

Unless the rate of progression from the point of a screen-detected abnormality to a clinically detected abnormality is known, it is very difficult to figure out whether a treatment of the screen-detected tumor is actually improving survival when compared to tumors detected later. To do so, the lead time needs to be known and subtracted from the group with the test-based diagnoses. The problem is that the use of the more sensitive detection tests usually precede such knowledge of the true lead time by several years. The adjustment for lead time assumes that the screening test-detected tumors will progress at the same rate as those detected later clinically. However, the lead time is usually stochastic. It will be different for different patients, with some progressing rapidly and some progressing slowly. This variability is responsible for a second type of bias, known as length bias.

Length bias refers to comparisons that are not adjusted for rate of progression of the disease. The probability of detecting a cancer before it becomes clinically detectable is directly proportional to the length of its preclinical phase, which is inversely proportional to its rate of progression. In other words, slower-progressing tumors have a longer preclinical phase and a better chance of being detected by a screening test before reaching clinical detectability, leading to the disproportionate identification of slowly progressing tumors by screening with newer, more sensitive tests.

https://fivethirtyeight.com/features/the-case-against-early-...

>What’s clear is that cancers fall into a few general behavior patterns, which Welch and others have compared to animals that must be kept in the barnyard to prevent a deadly rampage. Papillary tumors are like turtles — they move very slowly and never pose an escape risk. They don’t need screening, because they will never cause trouble. Then there are rabbits, which are eager to hop away to other parts of the body, but can be confined if they’re found and fenced. These are the cancers that can be helped by early detection and treatment. Birds, on the other hand, are so flighty and quick that they can’t be confined. Screening makes no difference for bird cancers, because they’re so aggressive that they can’t be detected before they’ve begun their deadly course.

>No cancer screening has ever eliminated the majority of cancer deaths. Instead, the best screening can do is reign in the rabbits. Birds remain unstoppable, and they’re the ones responsible for most cancer deaths. This is why, Welch says, three decades of mammography have failed to put a dent in the rate of women presenting with metastatic breast cancer upon their initial diagnosis. Women with breast cancers that behave like birds will almost never be helped by a mammogram, nor will men with the most aggressive prostate cancers be saved by PSA tests.

Edit: removed incorrect assumption about poster

Preemptive testing is useful and done for people with history of early cancers in family but obviously can detect only germline mutations. Most of the targeted therapies target somatic mutations.

Some hospitals doing genomic testing share their data through AACR GENIE project

https://www.aacr.org/Research/Research/Pages/aacr-project-ge...

One interesting study on breast cancer patients receiving radiotherapy, found that local control was obtained but more women were eventually dying from heart failure from being in the radiation field. This essentially offset the gain. This couldn't be seen with 5 year survival rates. Now physicians are focused on protecting the heart and hopefully, eliminating cardiac toxicities.

That vignette just shows that 5y survival is a difficult metric and only shows a small piece of the picture. Others have rightly pointed out, stratification of data based on stage would be helpful. Improvement in 5 year survival of stage 4 patients, could be very meaningful.

Unfortunately, new treatments are adding months (on average) not years.

The best thing we (as a country) did, was wake up to the dangers of smoking. When per capita cancer diagnoses decline and survival rates remain steady (or improve), then we know more people are living longer.

In general the goal with Oncology is to help people live longer, and improve quality of life for people with cancer. 5 year survival rates are one broad metric which probably broadly indicates they’re getting better at fighting the disease on those fronts.

There is lots of scary stuff out there, I'm aware of that. Maybe it's also about the "actio = reactio" thing in my head. Crash = you may die or be severly injured. Overweight might lead to strokes, ok. I can grasp all of those concepts and understand them.

But cancer can just come out of nowhere and it could kill you, although you did nothing wrong.

I think the first step is to focus on things that we don't have a solution for. Having good diet and exercise is a fairly comprehensive solution, no matter how hard it might be to maintain a lifelong strict regimen (as long as you're able to have such a regimen, your chances of the circulatory system going bad are slim to none).

In the case of organ failure, we don't even have anything other than reliance on organ availability from others.

https://www.cdc.gov/vaccines/programs/vfc/index.html

Bring 18 or under and uninsured is enough to qualify. To your credit, public awareness of this may not be everywhere.

Cosmetics are a bit of a black box, but what carcinogens are supposed to appear in soaps, shampoos, detergents, or most common cleaners?

The ~power of mainstream is high, it's not super easy to swim across the flow