There’s no single type of cancer, and the term actually refers to a large number of diseases that originate in different parts of the body. That may cause some confusion about what exactly cancer is and how it develops.
Cancer is a disease that develops when your body’s cells suffer genetic changes that cause them to grow and divide out of control.
Normal cells grow and divide in a highly controlled manner, with new cells created to replace dying cells. Cancer cells cannot stop growing and dividing, and they can spread to other parts of the body and cause damage to tissues. Cancer cells evade your body’s natural defenses, and can adapt to different environments in your body.
The exact causes and mechanisms of cancer may vary depending on the type of cancer, but cancer generally refers to all diseases in which cells suffer from uncontrollable division.
How Does Cancer Start?
Cancer has a variety of different causes. The main factors are:
- Genetic Errors: Errors occur during the cell division process that results in the proliferation of defected cells.
- Genetic Inheritance: Some types of cancer, such as breast cancer, can be inherited by one’s parents, resulting in genetic predisposition to that particular type of cancer.
- Environmental Factors: Cells can be damaged by external agitators that exist outside of your body, such as tobacco smoke, radiation, carcinogens, alcohol, and poor diet.
Types of Cancer
There are two main types of cancer:
- Hematologic (blood) cancers are cancers of the blood cells, including leukemia, lymphoma, and multiple myeloma.
- Solid tumor cancers are cancers of any of the other body organs or tissues. The most common solid tumors are breast, prostate, lung, and colorectal cancers.
What is Cancer Staging?
Cancer staging is a process that maps how much the cancer has spread within the body. It’s a critical tool in determining the best types of treatment for a patient. Staging typically involves:
- Physical exams
- Tumor Markers
The TNM system (which stands for Tumor, Node, and Metastasis), is the most commonly used staging system. TNM will classify a cancer based on:
- The size of the primary tumor
- Whether or not cancer cells have spread to nearby lymph nodes
- Whether the cancer has spread to other parts of the body.
- Once these are determined, the cancer is assigned a stage from Stage 0 to Stage 4. Stage 0 cancer is a cancer that’s in its very early stages and hasn’t yet spread. Stage 4 cancer is a cancer that has advanced significantly from its origin point and spread to distant parts of the body.
Generally, cancers that are detected at earlier stages are more likely to be effectively treated. Cancers at a later stage may require more aggressive treatments and are typically more difficult to combat.
Cancer treatment aims to destroy the cancerous cells that are spreading in the body. There are a variety of different treatment methods that may be used, depending on the type of cancer and its severity. Common treatment methods include:
- Removal of Tumor: If the cancer has originated in a cancerous tumor, then surgical removal of the tumor may be required to prevent the cancer from spreading.
- Radiation Therapy: The patient is exposed to high-energy radiation (typically X-rays and protons) that kill cancer cells. The patient may need to receive daily or weekly doses for several weeks, depending on the severity of the cancer.
- Chemotherapy: Chemotherapy employs drugs that attack rapidly-growing cells (i.e. cancer cells). The drugs can be administered orally or through I.V. Typically, the patient will take the drugs over a short period of days, followed by a period rest and allow the body to recover.
- Immunotherapy: Immunotherapy refers to a variety of treatment methods that focus on boosting the immune system’s ability to fight cancer cells. Treatment for certain cancers may involve T-cell transfers, in which the body’s most effective T-cells are isolated from a patient, sometimes genetically modified to enhance their ability, multiplied in a laboratory, and then re-administered to the patient. Treatment may include immune checkpoint inhibitors which block cancer cells’ ability to hide from the immune system.
- Hormonal Therapy: Certain cancers, like breast cancer and prostate cancer, use hormones to grow. Hormonal therapy inhibits the body’s ability to produce hormones so the cancer won’t be able to grow as quickly, allowing sufficient time for other treatment methods to take effect.
- Targeted Therapy: Targeted therapy refers to a variety of cancer treatments that interfere with specific genes or proteins that cancer cells use to grow.
Most often, multiple cancer treatments are taken in conjunction with one another. While the treatments are generally effective at killing cancer cells, they also cause major side effects in patients that include pain, dizziness, fatigue, nausea, and hair loss.
There is no single cure for all types of cancer, and Stage 4 cancer often has a poor prognosis. That’s why cancer research is important. Medical researchers continue to try and develop new drugs and treatment techniques that could cure and eradicate cancer altogether. New drugs and treatments are put through clinical trials to test their effectiveness