The manifestation of cancer begins when the cells in the body multiply out of control. There are various kinds of cancer with each type starting with the out-of control rapid growth of cells. In most cases, the rapid multiplication of the abnormal cells leads to the growth of tumors. Tumors can either be benign or malignant. Benign tumors are neither cancerous nor life threatening due to the fact that they do not move to other body parts. Malignant tumors cause cancer and are capable of spreading to other body parts close to the tumor. Malignant tumors are capable of moving to other parts of the body. This is facilitated by the lymphatic system and blood vessels through a process known as metastasis (Devita and Rosenberg 2213).
There are various factors that enhance the risk of contracting cancer including exposure to harmful chemicals, radiation, some bacteria and viruses and bad lifestyle such as heavy consumption of alcohol and smoking. There are more than 200 cancer types that have been identified. A variety of risk factors including lifestyle behavior, age and genetics contribute to the increased risk of developing cancer. One risk factor is not entirely responsible for causing cancer but a combination of several of them. Daily exposure to harmful chemicals increases the risk of getting cancer. Some of the carcinogenic chemicals include arsenic, benzene, asbestos, vinyl chloride and beryllium. Other chemicals cause cancer among animals but have not been identified to cause cancer among human beings. Examples include DDT, polychlorinated biphenyls, chloroform and formaldehyde. These are classified as possible human carcinogens.
Normal cells have the ability to pass information between themselves and other cells. The ability to coordinate information between the cells helps to integrate and regulate cell growth and cellular functions. However, with the development of cancer, the cancer cells are not controlled by the normal mechanisms (Rofstad 591).
The human body has the ability to develop defense mechanisms against the various harmful exposures including those that lead to the development of cancer. The damage of DNA cells can lead to the development of cancer. If the damaged DNA is not repaired, it can result in mutations of genes leading to cancer. The figure below illustrates how cells respond to chemical injuries (Cheung-Ong et al. 649).
Cancer therapy
A large number of people diagnosed with cancer are surviving due to early detection and quick and effective treatment. Screening is important in order to check the body for any traces of cancer before the symptoms manifest. The tools that help in diagnosis of cancer include: biopsy, ultrasound, x-ray, computer tomography and magnetic resonance imaging (Hosoya and Miyagawa 376).
Biopsy involves the removal of the affected tissues by a doctor under the observation of a microscope. Ultrasound uses reflected high-frequency sound waves for the examination of body tissues. Computed tomography (CT) utilizes x-rays to generate cross sections of diagrams of the affected body parts. On the other hand, magnetic resonance imaging utilizes both radio waves and magnetic fields to highlight alterations within the soft tissues. Other methods employed for diagnosis of cancer cells include HPV DNA tests that identify DNA from cancer inducing HPV types in the cells of the cervix and pap tests that identify abnormal cells in the cervix.
There are various ways that can be employed to manage the harmful effects of cancer. Small and localized cancer can be removed through the process of surgery. Radiation can also be employed after surgery to control the growth of small tumors that were not successfully removed through surgery. Chemotherapy can also be employed to destroy tumors that cannot be removed through surgery or radiotherapy. Chemotherapy used after surgery eliminates the residual cancer cells in the body and is therefore termed as adjuvant therapy (Cheung-Ong et al. 653).
References
Cheung-Ong Kahlin, Giaever Guri and Nislow Corey. “DNA-damaging agents in cancer chemotherapy: serendipity and chemical biology.” Chemical Biology, 20.5 (2013): 648-659.
Devita Vincent and Rosenberg Steven. “Two hundred years of cancer research.” New England Journal of Medicine, 366.23 (2012): 2207-2214.
Hosoya Norikoand Miyagawa Kiyoshi. “Targeting DNA damage response in cancer therapy.” Cancer Science, 105.4 (2014): 370-388.
Rofstad Einar. “Microenvironment-induced cancer metastasis.” International Journal of Radiation Biology, 76 (2000): 589–605.
