Cancer Growth
In the simplest terms, cancer is a disease state characterized by uncontrolled cell division. Cancer can impact almost every part of the body; from our bones and blood blood, to our skin and other organs. Cancer is far too common, affecting upwards of 40% of people at some point in their lives.
Why do cancers occur so often?
How do cancerous growths come about?
Cell Division
Cancer is characterized by uncontrolled cell growth. Cells tend to gather enough resources and grow until they are able to divide. At this point, they enter the microbiological process of mitosis where they divide into 2 offspring cells. These offspring cells operate as the parent cell operated, gathering resources, importing and exporting molecules with their neighboring cells, and into the extra-cellular matrix. Cell division is offset by the process of apoptosis. In adult humans, these two processes (mitosis and apoptosis) are in fine equilibrium with each other, ensuring that organelles and tissues maintain themselves at a stable size.
However, as cells divide over and over, throughout the course of a human’s life, their DNA is prone to developing mutations. These mutations can impact a cell’s function, including — depending on what gene(s) the mutation(s) impacted — the processes of mitosis and apoptosis. Tumors form when mitosis occurs far more often than it should and/or apoptosis occurs far less often than it should.
Tumor Formation
A cancerous mass forms when there is a disruption in the equilibrium between apoptosis and mitosis. This can lead to an uncontrollably high rate cell division, and result in the formation of a small mass called a hyperplasia. Hyperplasias are hard to detect, but don’t always progress into cancer. Hyperplasias are just an increase of the amount of cells for a specific type of tissue. Cellular and immune defense mechanisms are often able to halt a hyperplasia from continuing to the next level of growth: a dysplasia. A dysplasia is a continuation of a hyperplasia growth, and can progress into a tumor (a.k.a a an “in situ cancer”). If the tumor is malignant, then it may need treatment to prevent the tumor from damaging the organ where forms, and to prevent it from spreading to other parts of the body. Benign tumors, on the other hand, are not as problematic. They don’t become metastatic (spread to other areas of the body) and they usually don’t damage the organ where they form.
Breast Cancer
The most common type of breast cancer is called invasive ductal carcinoma. This is where a tumor forms among the duct epithelial cells. The mammary gland has three types of tissues; adipose tissue (surrounding fat), lobules, and the ducts. The lobules are responsible for producing milk, and the ducts are responsible for transporting the milk from the lobules to the nipple. All humans have mammary glands (besides those who have had a mastectomy). About 1 in 8 cisgender women and 1 in 20 transgender women are diagnosed with breast cancer at some point in their lifetime (with lower rates for cisgender and transgender men along with nonbinary individuals). Cisgender women are most prone to cancer because the ductal cells reproduce at a high rate and on a regular basis. This occurs as a response to hormone based chemical signals as part of the normal menstrual cycle. Anytime cells have a high reproduction rate, they are more prone to cancer. This is because any time mitosis occurs, DNA replication occurs. Every time DNA replication occurs, it opens up the possibility of random mutations occuring, which could result in a mutation that signals for accelerated cell division.
