Cancer is one of the most dreaded diseases of all time. It was considered as a disease that cannot be remedied except for the medical breakthroughs in the past half century. So deep is cancer’s fear that it instills depression in its sufferers as soon as its name is mentioned. However, thanks to medical breakthroughs it is curable and the media emphasizes on this night and day. What is cancer and how does it spread, what are its kinds and how it influences the society? An attempt has been made answer these questions in the following article.
Keywords: malignant neoplasm, cancer, carcinogen
The human body is the perfect machine, one of nature’s best creations. It can feed itself, clean itself, grow multiply, repair, show emotions and intellect. Unlike most species that inhabit the earth, the human body is by far the most adaptable of all. But this near-perfect machine has flaws as well. It ages and dies. It is affected by problems known as diseases and disorders; diseases and disorders that harm the human body to weaken, and to kill at extremes. Most of these diseases are easily curable and some not that easy at all. Cancer is one such disease that has cure, but yet inspire fear amongst all population. It is one of the most painful of ailments. Even the cure is painful. Named as malignant neoplasm in medical terminology, cancer is one of the deadliest diseases known to man. But what exactly is malignant neoplasm or cancer? Is it curable? Can people suffering from cancer be cured and return to normal life. The following article discusses the disease, its biological significance and its cure in brief.
Cancer or malignant neoplasm, in medical terms is essentially a malfunctioning of body at the cellular and tissue level. It is a broad class of diseases that afflict different organs and tissues of the human body. In short, it is a form uncontrolled harmful outgrowth, caused due to abnormal growth of tissue and cells that inflicts damage to the normal functioning of cells and tissues. The malfunction begins at a very fundamental level. There are many factors that basically affect the most important part of any cell, the genetic makeup. These factors, called carcinogens, trigger cells to grow and multiply uncontrollably, causing formation of massive lumps of tissue that do not function properly or cause obstruction (Cleaver and Mitchell, 2000). This process of change of genetic make-up is called as mutations. These affected cells produce carcinogenic effects on all the cells they come in contact with causing multiple tumor-like growths. In fact cancers are much like tumors, only that the do not just sit as extra outgrowths of tissue, they spread and multiply causing damage to body functions. One of the most damaging characteristics of cancer is that it spreads to other parts of the body as it advances through different stages. Cancer spreads through the circulatory and the lymphatic systems to other organs after it dislodges from the initially affected tissues. The reasons for cancer being such an important subject medical sciences is the fact that cancer occurrence is on the rise every day. The cure for this disease is difficult and many die merely due to sheer ignorance or the depression of the disease. There are many types of cancer, there cause of development, spread, diagnosis and cure are different too. Each of these is described in the subsections that follow.
Cancer may be caused due to many reasons, from hereditary to carcinogenic (cancer causing) chemicals. Each reason causes cancer in a different part of the human body. But most of them develop as tumor like outgrowths which after a certain span of time break from the initial tissue and spread through the circulatory and lymph systems to attach new target tissues where they settle and multiply to form multiple cancer spots in the body. Some of the general causes are listed below
- Chemicals – these form the first and foremost reasons for increasing incidence of cancer. These chemicals enter the body through air, water or any physical agent that may come in contact with the inner body tissues. Smoking and drinking are the major causes of cancer as they constitute an intake of high quantities of carcinogenic chemicals. Sasco, Secretan and Straif in their article (2004) describe, “Tobacco smoking is associated with many forms of cancer, and causes 90% of lung cancer.” Other carcinogenic chemicals include asbestos, cobalt, nickel, quartz, cristobalite, tridymite and man-made materials like glass wool, rock wool etc. These chemicals when enter the body in large quantities, trigger cancer like development in the body. Most of these chemicals are part of occupational hazards and
- Infection –cancers caused due to exposure to certain infections cause nearly 18% of the total deaths that occur due to cancer (Anand et al, 2008). These infections are caused by viruses and bacteria, and more frequently found in developing countries than the developed ones (Park, 2008). Such caner causing viruses and bacteria are known as oncogens. These infections can affect a large spectrum of places in the human body, depending upon how they enter the body.
- Radiations – radiation exposure has been known to mankind as another major cause of mutation as well as cancer. Long durations of radiation exposures lead to cancers, most common of which are cancers of the skin caused due ultraviolet radiation exposure (Cleaver and Mitchell, 2000). These radiations can be of both ionizing and non-ionizing type, the most common being the non-ionizing type of radiation.
- Lifestyle and diet – a person’s exercising and dietary habits determine the chances of contracting cancer. Diet, physical inactivity, and obesity are related to approximately 30–35% of cancer deaths (Anand et al, 2008). Physical inactivity not only increases the body weight, but also affects the immune and endocrine system, leaving the body with weakened defense against cancer. Other dietary habits like chewing betel nut, eating processed high protein diet, excessive salts etc. all lead to cancer. Drinking scalding tea and coffee are also quoted as reasons for some cancers of the throat and esophagus (food pipe) (Irigaray et al, 2007).
- Heredity – mostly cancer cases are non-genetic in nature. Hereditary cancer occurs through genes that have been passed on through genes that may later develop cancer. The comparative frequency is low, and genetic carriers are termed as individuals at high risk of developing the disease.
- Others – repeated relapse into certain diseases, repeated trauma of certain tissues etc. Can trigger the formation of cancers. Cancer is not a transmissible disease occurring with rare incidents of transfer through pregnancy or through organ transplant from poorly screened organ donors.
How it occurs
There are mechanisms that control the mechanism of tissue growth, keeping in check the unnecessary growth of tissue and cells at all sites in the body. Cancer is essentially the failure of this very tissue growth control mechanism (Kinzler and Wogelstein, 2002). Genes that control the cell growth and differentiation fail due to alteration causing the cells to grown and divide uncontrollably. This leads to tumor like activity. But cancer is different from tumor as it inhibits the functioning of the tissue, causing painful ulcer on the tissue. The process of cancer can happen due to over expression of cell growth genes, known as oncogenes or due to under expression of tumor inhibitor genes that control the growth and division of cells. However, developing a cancer requires changes in multiple genes. These changes are insertion deletion and mutation of genes in the DNA (deoxy-ribo nucleic acid) sequences that control the basic functioning of the cells (Kinzler and Wogelstein, 2002). Once the normal functioning has stopped and over growth is possible, cells multiply and cause an amplified recurrence causing the cancer ulcer to grow rapidly.
Cancer patients in many cases do not develop any specific symptoms. Rather their symptoms resemble symptoms of some other diseases that the patients may get treated for. However, there are few symptoms that are unique to cancer. Most of these symptoms are minute and only few are very obvious. As in the case of the respiratory tract, most of the cancer symptoms include frequent recurrence of pneumonia, breathlessness and gasping, also symptoms in many other diseases (Anand et al, 2008). Other symptoms may include fevers of unknown origin, as in the case of renal cancer, or blood in urine, in case of cancers of the urinary tract. The main reason for cancer being termed a dangerous disease is its low chances of being detected and identified in the early stages.
Cancer can be detected through screening methods like X-Ray photography, blood tests, CT scans etc. However, confirmation requires a pathological tissue sample. Detection cancer in the early stages is highly crucial as remedy in the later stages becomes difficult as the cancer dislodges and spreads through the body, creating multiple sites for cancers. Medical sciences have developed techniques like radio tracing etc. for early detection.
Cancer can be broadly subdivided into five categories. These are carcinoma, cancer of the epithelial tissues; sarcoma, cancer of the connective tissues; lymphoma and leukemia, cancer of blood corpuscles and lymph; germ cell tumor, caused in the reproductive organs of males and females; and blastoma, cancers of embryonic tissues. All of these types affect different organs and regions of the body. However, the development of a cancer tumor is very painful and depressing and in most of the cases the affected tissues need to be removed followed by lengthy procedures like chemotherapy, which leave a deep psychological impact on the patients.
Cancer has a cure (Kinzler and Wogelstein, 2002). However it needs to be detected at the earliest and countered through rigorous and careful measures. This may include removal of the diseased tissue or organ completely from the body, treatment through chemotherapy, or both with a spectrum of medicines to help the body to recuperate and maintain defenses against other diseases (Cleaver and Mitchell, 2000). Medical science has developed many methods in attempt to reduce the mental and physical pain of cancers. However, the main issue lies in the sheer amount of psychological stress that a person goes through when faced with the fact that they have the disease (Kinzler and Wogelstein, 2002). One should know that cancer is curable, with a rigorous medical regimen.
There are many diseases that have been termed as incurable and cancer is one of them. However, cancer is curable and medical science strives to find a cure for this disease. What one must know is that the key to fighting such a disease is to remain psychologically strong and fight to survive. People should get themselves regularly checked especially in case of recurring medical conditions and should not refrain from getting advice (Anand et al, 2008). Medical science can help only when people get actively involved instead of showing sympathy for patients alone.
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