Do you have any evidence you can point to for this assertion? The book Good Calories Bad Calories has a section that reviews the literature on the subject. Disease and Western Civilization reviews specific populations in detail. Nutrition and Physical Degeneration for a geographically diverse primary source although it’s not about cancer or longevity.

The assertion that older people get cancer more than young people? You could try any medical source whatsoever that deals with cancer or longevity, instead of picking one that doesn't, e.g. [0]

> Advancing age is the most important risk factor for cancer overall and for many individual cancer types. The incidence rates for cancer overall climb steadily as age increases, from fewer than 25 cases per 100,000 people in age groups under age 20, to about 350 per 100,000 people among those aged 45–49, to more than 1,000 per 100,000 people in age groups 60 years and older.

[0] https://www.cancer.gov/about-cancer/causes-prevention/risk/a...

That study doesn’t include hunter gathers. Certainly cancer rates increase for them as they age as well. The point is the rate is orders of magnitude less than we experience today.

Who was diagnosing hunter gatherers with cancer?

I lost my wife to melanoma that spread to the brain. I don’t know how some hunter gatherer society would detect a brain tumor.

Frontier doctors diagnosed cancer in hunter gatherers the same as with non-hunter gathers. Except the hunter gatherer diagnosis was so rare that they could write a case report about it.

Sorry for your loss. We all have lost loved ones to cancer today. It didn't used to be that way. Cancer is one of the many afflictions known in academic literature as "Diseases of Civilization". It's incidence is increasing in our society at any given age, so it's not because we are living longer.