Cancer: An Overview
Cancer is an abnormality in cell proliferation i.e. not age, race, or gender-specific. It depends on the exposure to carcinogens like tobacco, UV radiation, etc., causing damage to the DNA (Barnes, 2018). In addition, there are certain lifestyle-associated carcinogens that directly or indirectly led to cancer. These include processed food, alcohol consumption combined with smoking, air pollutants (Anand, 2008), harmful chemicals released as a result of industrialization, etc. (Mitchell, 2021). Several studies have also shown that less than 10% of cancer is caused by genetic modifications (Edlich, 2005) whereas, the rest percentage is caused by carcinogenic agents, associated with environmental lifestyle factors. The cell-cycle damage (Barnes, 2018), failure in restoring the cell-repair mechanism (Kudravi, 2000), alteration in genes associated with cell growth (Hoenerhoff, 2022), and hormone therapy like breast enlargement (Rastelli, 2008) induce the development and advancement of cancer (Hoenerhoff, 2022). With the two major categories of benign and malignant, cancer can be classified depending on the parts of the body it is affecting. There are morphological differences between benign and malignant tumors. A benign tumor can become quite large, but it will not invade the nearby tissues or spread to other parts of the body. On the contrary, a malignant tumor can spread to other parts of the body, causing multiple organ failures, especially in the last stage. (Stavros, 1995) A diagrammatic representation illustrating its different types is shown in Figure 1. This showed various cancer types categorized with the subtypes and properties.
Figure 1. Cancer overview with two major categories (i.e., benign and malignant) along with its various types
The mode of treatment (Table 1) is dependent on the stage at which the cancer is been diagnosed. Including stage zero which is also called pre-cancerous, there are 5 stages leveling up from 0 to 4. Cancers that belong to stage zero are usually easy to treat and are considered to be a pre-cancer stage by most healthcare practitioners. Stage one and two tumors are specific to a particular area and can grow without affecting another cell. Till this stage, most of the cells can be benign. The malignancy occurs from stage three where the mass grows larger and coverage is till the lymph node and the surrounding tissues. Stage four is the last stage where the tumor outgrows and spreads through the entire body affecting several neighboring organs. This phenomenon of spreading and affecting is also called metastasis (Mustafa, 2016). The conventional methods consist of performing cytology on samples, scanning the affected area using X-Ray, CT, MRI, Sonography, etc., or undergoing Biopsy (Frangioni, 2008).
Table 1. The common treatment with its action mechanism
Treatment | Action Mechanism | Reference |
Chemo-Therapy | High power drugs | Chabner, 2005 |
Radiation-Therapy | High dose of radiation | Schaue, 2015 |
Hormone-Therapy | Hormonal dose | Drãgãnescu, 2017 |
Immuno-Therapy | Induce immune response |
Couzin-Frankel, 2013
|
Bone Marrow Transplant | Damaged cells are replaced with healthy cells | Curtis, 1997 |
Sometimes with higher cancer coverage, the combination of treatments is implemented on the patients risking their survival rate. Moreover, these treatments have higher side effects like hair loss, appetite loss, nausea, fatigue ness, etc., and sometimes affect the psychology of the patient.