Yes, people have had cancer at all times . In addition to the fact that traces of the disease can be found on ancient Egyptian mummies, descriptions of cancer have been preserved in ancient texts. For example, in Edwin Smith's famous Papyrus. And the very term "cancer" ("carcinoma") was invented by the ancient Greek physician Hippocrates . He compared a malignant tumor to the claws of a cancer or a crab that grow into surrounding tissue. Moreover, malignant tumors appeared long before humans; this is a common misfortune of most multicellular organisms. For example, traces of tumor lesions are found on the bones of dinosaurs.
Modern scientists believe that the prevalence of cancer in the modern world has increased mainly due to the "aging" of the population. People began to live longer, less likely to die from other causes. Oncologists have a saying: “not everyone lives to see their cancer,” because with age, more and more mutations accumulate in the cells of the body, and the risk of malignant transformation increases. In addition, diagnostic methods are improving, modern doctors are increasingly detecting cancer at an early stage, and due to this, it also seems that the incidence is growing.
Of course, external factors also play a role. These are bad habits, and unhealthy diet, and pollution of air, water, soil, and a sedentary lifestyle, and a general epidemic of excess weight.
They were sick, but cancer was not the most common disease in those days. Previously, it was possible to glue fins against colds even. In the 21st century, severe diseases that are difficult to treat have become much less, and therefore cancer has come forward as the most common.
Always sick. Even Egyptian mummies have signs of oncological diseases described (not so often, but the diagnosis of diseases after millennia is not easy). Why this problem has become more urgent now? Many factors. Life expectancy has increased (cancer diseases are more often manifested in old age) ; improved diagnostics and treatment; there seems to be a real increase in oncological diseases, although it is rather difficult to assess, but examples from the 20th century show that this is the case (well, a striking example of the growth of colorectal cancer in Western countries due to changes in diet ).
No, I haven't been sick before. And why? Yes, because earlier they simply did not live up to cancer.