The Emperor Of All Maladies

The Emperor Of All Maladies details our understanding of cancer, from how we first discovered it, to treating it, and, hopefully, in the future, entirely preventing it.

Around 160 CE, Greco-Roman physician Galen developed the first known theory about cancer. He believed that tumors resulted from entrapment of black bile—this theory held until the sixteenth century when people started to perform autopsies.

Physicians were surprised to discover that there was no black bile to be found in cancer patients. So they instead turned to external, invisible sources. Until 1850 it was believed that poisonous vapors known as miasmas and worms caused tumors.

Once pathologist Rudolf Virchow looked at cancer under a microscope, he made a significant discovery. Cancer is actually made up of our own body’s cells.

But if they are made of our own cells, how can they be so deadly? Cancer cells are different from regular cells because they don’t die, and they don’t stop replicating. Normal cells divide when they get growth signals from their environment, and they stop when they receive signals from growth inhibitors.

Cancer cells, on the other hand, have mutated growth genes. This means that they both replicate without any signal and won’t stop replicating even if there are growth inhibitors. This is one reason why cancer is so hard to treat.

Another reason it is so dangerous is that, unlike a normal cell that ages and self-destructs, cancer cells never die. This immortality, combined with cancer’s unlimited replication, makes it very lethal.

We know that cancer happens in our own cells, but we also know that external sources can cause it. Percival Pott first discovered this when investigating a cluster of scrotal cancer among young boys. They were all chimney sweepers, and the soot accumulating on their scrotum caused the cancer. Since then, we have found countless other substances to be cancer-inducing, such as asbestos and heavy metals. How do these substances cause cancer? First, substances called mutagens alter your genes to cause problems in cell growth, self-repair, or self-destruction, making a normal cell transform into a cancer cell. The second step in the development of cancer is an immune system disruption that causes your body to no longer destroy a potentially malignant cell. Certain toxins can disrupt your immune system in this way. When a malignant cell isn’t destroyed, it can multiply unchecked, resulting in cancer. Infection also increases our cancer risk. Some viruses induce chronic inflammation, which damages cells in the infected tissue. Others directly cause cancer by altering a cell’s DNA, such as hepatitis-B. Other causes are radiation, hormones, and genes. Radiation causes cancer by damaging the DNA, which leads to mutations that become cancerous. Certain hormones can increase…