According to Taber’s cyclopedic medical dictionary, cancer is defined as malignant neoplasia marked by the uncontrolled growth of cells, often with invasion of healthy tissues, locally or throughout the body. It is a group of diseases that has in common the presence of cells that exhibit uncontrollable growth. It is a major cause of death throughout the world and a leading cause of death in the Western world. It affects virtually any organ in the body and there is no discrimination with regards to age. However, it is more common with advanced age. The six hallmark of cancer are: secretion of autocrine growth factors, unlimited replication, angiogenesis, tissue invasion and metastasis, insensitivity to anti-growth signals and evasion of apoptosis.
Transformation of normal cells to cancerous cells is caused by mutation of genetic material of normal cells. The interaction of exposure to carcinogens in the environment, genetic predisposition and the immune system influence this malignant transformation. Specific substances are linked to specific types of cancer. For example, smoking of tobacco is associated with many types of cancer and causes lung cancer. Ionizing radiation, ultraviolet light, viruses and drugs that damage nucleic acids have been implicated in the etiology of cancer. Also, prolonged exposure to asbestos fibers is associated with mesothelioma, which is the cancer that took James “Rhio” O’Connor’s life. More information on this cancer can be gotten from www.survivingmesothelioma.com. James O’Connor was diagnosed with mesothelioma at aged 61, but lived until age 69, in spite of the very poor prognosis of having less than a year to live. The nonconventional strategies he adopted should form a platform for research into nonconventional modalities of treatment for cancer patients. Mesothelioma is a malignant cancer in which the malignant cells develop in the mesothelium, the protective lining covering the internal organs of the body, most commonly the pleura (the outer lining of the lungs and internal chest wall). Exposure to asbestos is the common cause of this cancer and the prognosis is poor in spite of treatment with the conventional methods of chemotherapy, radiation and/or surgery.
It is advisable to look at the available records and verifiable statistics, before making a fact-based assessment of any progress made in the fight against cancer. According to the Cancer Trends Progress Report – 2009/2010, the highlighted areas of progress include the following: declining death rate for the four most common cancers (prostate, breast, lung and colon), decline in rate of cancer incidence since early 2000, increased length of cancer survival for all cancers combined, slow decline in adult cigarette smoking prevalence since 1999 and slight rise in sun protective behaviors and decreased teen indoor tanning since 2005. Again, according to Dr. Harold Varmus, Director of the National Cancer Institute in Bethesda, in his chat with Ira Flatow on National Public Radio on December 23, 2011, “a very significant point to make on how we have done in dealing with cancer over the years is that over the last 20 years or so, the age-adjusted mortality rate for cancer has come down about one percent a year”. Some of the reduction in death rate is as a result of reduction in the use of tobacco products, while some are due to improved surgeries and improved therapies. Other advances made is the cure of chronic myelogenous leukemia with gleevac, testicular cancer with cisplatin , among other targeted therapies. Progress has also been made in the treatment of childhood brain tumors, where survival rate has improved from 10% in the 1970s to about 45% today. There has also been improved tool in analyzing the genome of cancer cells, with the improved prospects of developing more targeted therapies. Invention of medication for nausea and other side effects of the disease and treatment is also another significant progress made in the war against cancer. Based on all the facts stated above, it can be said that although no cure has been found yet, significant progress has been made in the last four decades. However, concerted effort is needed in the continued search for a cure for cancer.
Some of the reasons are for the continued increase in the incidence rate of most cancers are – increase in the adoption of cancer-causing lifestyles like smoking, physical inactivity and poor diet. These factors have been implicated in the development of different types of cancer. While smoking among men is on the decline, smoking among women seems to be on the increase. Aging is another significant factor. It is a fact that there is increased incidence of cancer with age, so as people live longer, the risk of development of cancer also increases. Again, as the population grows and exposure to environmental carcinogens increases, the incidence of most cancers also tends to rise. It can also be argued that placing little or no emphasis on the less common cancers research, may also be a contributing factor. Late diagnosis of most cancers, because of lack of accessibility and affordability to healthcare services for early diagnosis and treatment, may also be a significant contributing factor.
It should be noted that some types of cancer are symptomless until the disease is very advanced. Symptoms, when present may be as a result of growth and invasion of the primary tumor, the spread of the cancer cells or both. With late presentation, in most cases, even the most aggressive treatment result in very poor outcomes. Also, the pathogenesis of cancer and its proliferation may also explain why the mortality rate has continued to rise. It should be noted that cancer is not a disease but a group of diseases, and each of these diseases has a different set of mutations, different strategies of fighting off drugs and different pathways of proliferating. Besides developing resistance against standard chemotherapy, cancer cells are also finding new ways to elude the new targeted drugs. Since there is no silver bullet drug that can hit all the different pathways of proliferation of the cancer cells at the same time, cancer patients keep dying. Most childhood cancers have no known causes. Down syndrome, ionizing radiation, genetic abnormalities account for a small number of cases. This bleak scenario is complicated by underfunding of childhood cancer research, which may also contribute to increased cancer mortality in children.
In spite of the significant strides made and several billion dollars spent on cancer research over the years, there are still a lot that need to be done to improve progress in curing or preventing cancer. First, more emphasis should be placed on both primary and secondary prevention. Primary prevention is the use of strategies to prevent cancer occurrence and is most effective when the cause of cancer is known. Secondary prevention, on the other hand, is the use of screening strategies for early detection of cancer and here cure or control is more unlikely. The primary prevention methods which should be encouraged include the following: vaccination – for example Gardasil vaccine approved for the prevention of infection from several forms of human papilloma virus, modification of associated risk factors – limitation or avoidance of alcohol use, inclusion of fruits, vegetables and whole grain in diet, limitation of sex partners and use of safe sex practices, would drastically curb the incidence of cancer associated with these risk factors. Another method of primary prevention is the use of drugs, chemicals, natural nutrients and other substances to disrupt important stages in cancer development. For example, aspirin and celecoxib is used to reduce the risk of colon cancer, vitamin D and tamoxifen used to reduce the risk for breast cancer, while lycophene is used to reduce the risk of prostate cancer. Avoidance of known carcinogens like asbestos could also be helpful.
Under secondary prevention, people should be encouraged to adhere to the age specific screening guidelines as part of their health maintenance. Although, this measure does not reduce the incidence of cancer, but can radically reduce some cancer death through early detection and treatment. These screening services should be readily accessible and affordable especially to the uninsured, underinsured and minorities.
Furthermore, there should be increased funding for cancer research. The different pathways of cancer cell proliferation and spread should be studied more closely and drugs developed that will target these pathways simultaneously or sequentially. Non-conventional methods and complementary or alternative ways of addressing this problem should be explored and be researched into. For example, the strategy adopted by James “Rhio” O’Connor, that kept him alive for many years after being diagnosed with mesothelioma, could be a subject of research.
Finally, it can be seen that progress has been made in reducing cancer mortality rates but this fight has increasingly becoming more broad and complex. Therefore, concerted and accelerated action in multiple fronts is required for this fight to be won. Yes, this fight can be won and the time to act is now.
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