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.