Cancer is an umbrella term for a disease with a decidedly diverse appearance: the tumors that are grouped under this name affect virtually all human organs. The lungs are no more spared than the stomach and intestines, esophagus and skin, bones and brain, to name just a few examples.
A disease with many causes
Factors that trigger cancer appear to be at least as diverse as the manifestations of the disease: it is now known that it is not simply an “old-age disease,” even though age does play a weighty role in its development. Cancer can also be triggered by environmental factors: Sunlight promotes the development of skin cancer, and cigarette smoke produces lung cancer. On the other hand, gynecologists, for example, occasionally warn their patients when they find a certain virus in a vaginal smear. This can also cause cancer, which is why affected women should come in for regular checkups.
Cancer can also be inherited
To complicate matters further, cancer (or rather the tendency to develop cancer) is also occasionally inherited: the best known are hereditary breast cancer and hereditary colorectal cancer. In families burdened with this, an increased frequency of this disease is found.
Where does the name “cancer” come from?
By the way, the name was given to the disease by the ancient Greeks. The ulcers that form in breast cancer sometimes produce superficially visible, congested veins whose extensions have a shape reminiscent of a cancer. Moreover, the Greek word for the shellfish that runs sideways, “karkinos,” is the root for the technical word carcinoma.
What happens when cancer develops?
First of all, a cancer is a new formation of the body’s own tissue. Thus, it is not an “invasion” of a foreign pathogen that multiplies in the body (as is the case with bacterial infections). But how does it happen that something simply “starts to form and grow“? In principle, a cell – at first it is actually only one cell – breaks out of the regulations of the tissue association in which it lives and does its work, and begins to divide. The fact that cells divide and multiply is not an unusual occurrence, not even in the adult body. New cells are constantly being formed here, since the skin, for example, as well as the mucous membranes of the gastrointestinal tract and the cells of the blood are constantly renewed. Old cells are lost in return, they are exfoliated (in the case of the skin) or destroy themselves in a process scientists call apoptosis (Greek for “falling leaves”). This ensures that there is a balance of new formation and destruction. However, the proliferation that occurs in cancer development is not the sensibly controlled growth necessary for tissue renewal. Rather, the individual cell breaks out of this control and multiplies without having received “permission ” to do so.
Cancer is a “genetic” disease
The cell therefore multiplies “out of control” because the corset placed over it, which disciplines it and ensures that it lives in harmony with its neighboring cells, has cracked: it no longer recognizes or misunderstands the signals from its environment. These signals, which tell the cell whether it may divide or not, form the basis for the fact that in a multicellular organism “all work for one”, i.e. that the reproduction of individual cells is sensibly controlled for the organism as a whole. The corset of a cell, which makes it a useful part of the whole organism, is its genetic material. This contains the information on how the cell is to receive and interpret the signals from its environment. Therefore, if the genetic material changes, this interaction can also change. The cell, which previously faithfully performed its service for the organism as a whole in the tissue association, becomes a “deserter” that multiplies – without asking whether it makes sense to do so. The development of cancer is therefore always preceded by a change in the genetic material, which is why the disease is also called a “genetic disease” by many scientists. For all the diversity of the countless forms in which cancer occurs, the change in genetic information is the common denominator of this disease.And therein lies the key to understanding why cancer is triggered by so many different factors.
Cancer – a disease of old age?
If we look at the frequency of the development of cancerous tumors in relation to age, we see that 60 percent of all new cases occur in people who are older than 60. How can this be understood against the background that it is a “genetic disease”? Presumably, it is because the genetic material of human cells is very well protected against changes. Numerous systems, also known as “guardians of the genetic material,” constantly ensure that nothing happens to the “software of life. As a result, so few errors occur that it takes a long time for a change to actually occur, which then triggers cancer growth.
