Recent Advances in Medical Diagnostic Techniques for Cancer - Essay Example

Recent Advances in Medical Diagnostic Techniques for Cancer Introduction After cardiovascular diseases, cancer is number two among the leading death causes. In the United States half of men and one third of women get cancer in the course of their lives. Currently, many cancer patients can extend their lives through early detection and treatment. Cancer has been and continuous to be among the most distressing health problems all over the world. The disease is identified with its unrestrained multiplication and spread of abnormal cells (Bhardwaj, 2005). Cancer destroys the body and if untreated, can cause the health systems of the body to malfunction and eventually kill the affected person. Rapid technology advancement and increasing knowledge about the fundamental drivers of cancer continue to change the outlook of the disease. It is now clear that cancer is not one particular condition, but a conglomeration of diseases each of them having different features. Research into the causes of different cancers is underway. Some cancers result from environmental factors, such as exposure to the sun and smoking tobacco, but others are linked to infectious diseases (Kasahara & Tsukada, 2004). Researchers have achieved much development in the identification of genetic mutations and other factors related to mutations that may drive the haphazard formations and multiplication of cancerous cells. They have also advanced in the development of genetic markers that can be used to identify which patients have the highest risks of cancer development. These developments aid in better diagnosis and screening and also steer a new age of the management of cancer. This paper will discuss the recent advances in the diagnosis of cancer. How diagnostic techniques for cancer have changed over the past few decades Cancer screening is the process of testing and examining a person in order to detect the presence of a disease, such as cancer in a person with no evidence of symptoms. The Pap test was the first screening test that was used by many doctors for cancer diagnosis (Emole, 2012). The test was the result of George Papanicolaou’s experiments in his research of the menstrual cycle. Papanicolaou discovered that it could be used in early detection of cervical cancer and his discovery was publicized in 1923. Initially, many doctors did not believe him until the 1960s when the American Cancer Society (ACS) gave the test a boost that people started using it widely. Since then, there has been a 70% decline in deaths caused by cervical cancer (Ludwig & Weinstein, 2005). Modern mammography methods came on the scene late in the 60s and the ACS first recommended them in 1976. Over the years doctors have applied many other methods of diagnosis such as sampling methods applied in pathological examination. Some sampling techniques include incisional biopsy which involves the extraction of a section of a tumour to be diagnosed in the laboratory. This method is suitable for easily accessible lesions (Collins & Workman, 2006). Another technique is excisional biopsy makes it possible to have a better exam of the lesion. Therefore, it is the best for tumours. It has also been used extensively in the evaluation of lymph nodes. A doctor may also do needle aspiration through which he obtains a core of tissue from a bigger mass to be examined cytologically. This method is used widely for tumors that have a mass such as a breast (Kasahara & Tsukada, 2004). Cytology as a method has been in use in many places for the detection of cervical cancer and can be used for other cancers such as lung, bladder and gastric cancer. Apart from the above described sampling techniques, the diagnosis of cancers has also been done through specimens. After collecting tissue specimen, it is prepared before a histological exam. Specimen preparation may either be permanent or frozen parts. The permanent method comprises of the fixation, staining, sectioning and embedding (Collins & Workman, 2006). Diagnosis is also possible through molecular techniques. Since genomic alterations responsible for malignancy are so diverse, researchers have developed several assays for profiling tumors. Therefore, it is not enough to understand the histopathology of a cancer. Molecular diagnostics when combined with available histomorphological classifications in surgery affords doctors more stratification for a better prognosis of cancer (Bhardwaj, 2005). The identification of molecular markers within neoplastic tissues helps to get precise diagnosis, prognosis and response prediction. Cytogenetic procedures are important for understanding chromosomes so that changes in chromosomes can be tracked for the detection of certain unique types of cancer. They include FISH technique, PCR, DNA microarray analysis, Immunocytochemistry (IHC), Flow cytometry (Emole, 2012). Since when cancer peaked in 1991, the death rate of cancer has fallen significantly and researchers credit this to advanced diagnosis and treatment of cancer. New cancer diagnostic techniques are bringing meaningful outcomes for patients, improving the rates of survival and giving patients choices that in most cases are easily tolerated with a reduced amount of long term effects and in the process making the quality of life better (Ludwig & Weinstein, 2005). Over the years, cancer biomarkers have been among the fastest growing fields in clinical diagnostics. They are useful in the screening of asymptomatic people to help in specific early diagnosis to choose patients that can benefit from particular treatments to forecast prognosis and reaction to therapy and lastly to do monitoring for patients who have undergone primary therapy (Kasahara & Tsukada, 2004). For many years, conventional histopathology that functions on the basis of morphology assessment has been the standard method of diagnosis for several years. Enzyme electron microscopy and histochemistry broadened the fundamental micro-anatomic evaluation to bring in structural features of an ultra-structural and biochemical nature (Emole, 2012). In recent years, there has been progression whereby molecular genetic assays, immuno-histochemistry, analysis of DNA ploidy and cytogenetics are now being included as important additions to light microscopy in the diagnosis of cancer. The use of advanced technologies such as automated DNA sequencing, microarray and mass spectrometry have made new openings in the area of cancer biomarkers. There have been significant changes as well in oncologic imaging. Imaging is moving from spatial 2D AND 3D and spatial automatic images to the molecular, genetic, functional and biologic imaging. Immuno-histochemistry is an entrenched method that functions on the basis of the detection of certain particular sequences of proteins of tumors through the use of monoclonal and antisera antibodies that are directed against them (Ludwig & Weinstein 2005). It is significant in unclassified tumors, for example, undifferentiated tumors, lymphoid malignancies and round blue cell tumors. The popular immunohistochemical panels applied are cytokeratin in epithelial malignancies and HMB-45 for melanomas among others. The use of Immuno-histochemistry has been extensive and its importance has been determining, progesterone, Her-2 neu and estrogen receptor ability in breast cancer in the prediction of cancer to therapy (Emole, 2012). Emerging Technologies Morphological examinations happen to be the easiest cancer diagnostic methods. More advanced imaging and laboratory techniques have been invented in oncology through the years but doctors still rely on histopathology as a way of firmly diagnosing many of the solid tumours suspected of being cancerous (Collins & Workman 2006). It is only on specific occasions that clinicians have applied imaging and biochemical assays instead of examining tissue using a microscope. The diagnosis of cancer has witnessed the introduction of several new technologies to replace or function alongside conventional techniques (Kasahara & Tsukada, 2004). For example, the development of the intelligent surgical knife otherwise called the iKnife has brought many changes in cancer diagnosis. The iKnife was discovered by Zoltan Takats and it functions by use of an electric current to apply heat on body tissues and make slight incisions that minimize the loss of blood. With the use of an iKnife, the smoke in form of vapour is subjected to analysis using a spectrometer to identify what chemicals exist in the collected sample of blood (Ludwig & Weinstein, 2005). Through this method, there is a high possibility of the identification of malignant tissue. The iKnife significantly reduces the time taken for operations on patients. The most specific cancer bio-marker is the telomerase activity that is seen in somatic cancer cells and it is associated with the aggressive behaviour of tumours (Bhardwaj, 2005). Telomerase activity detected through telomeric repeat has been found in more than 90 percent of specimen obtained from body tissue. The detection of solid tumours in their early stages during routine screening is therefore predictable with telomerase activity in combination with imaging analysis (Emole, 2012). Currently, the most promising tool employed in routine diagnosis is pharmacogenomic testing. Contrary to conventional drugs used for cancer management, new targeting drugs must have corresponding molecular testing to aid in the selection of the appropriate dose for the right patient with lesser adverse effects and proper containment of costs (Ludwig & Weinstein, 2005). Imaging technologies through the use of different platforms have advanced considerably with the help of computer-aided technologies. Imaging diagnostics have the ability to detect a solid tumour as tiny as 10mm in diameter and they can also show the position of the tumour. Most of the conventional tumour markers used for diagnosis could be phased off in the future (Kasahara & Tsukada, 2004). There is need to investigate the emergence of new biomarkers for use in primary testing before imaging diagnostics or for certain particular tracers of imaging analysis. The creation of new biomarkers for testing before imaging diagnostics or for particular imaging tracing analysis is an option that should be investigated for early diagnosis of cancer (Bhardwaj, 2005). Benefits of the New Diagnostic Methods to the Patient, the NHS, and Healthcare New diagnostic methods for cancer detection hold many benefits for cancer patients, healthcare and NHS. If cancers are detected in their early stages and in good time, the number of people who lose their lives to the disease would significantly be reduced and successful treatment cases would increase tremendously and less people would suffer disability due to cancer related causes (Kasahara, & Tsukada, 2004). Early diagnosis is the early detection of cancer in people having the disease. This is not the same as cancer screening whose purpose is to identify unrecognized cancerous lesions in a population that is otherwise healthy. Early diagnosis and screening are very important in the successful control of cancer (Ludwig & Weinstein, 2005). Therefore, new diagnostic methods are very instrumental in the management and control of cancer. Early diagnosis is done on people with signs that point to the possibility of having cancer. The purpose is the identification of the disease when it is still early and when the opportunity for treatment still exists. In addition, early detection gives the patient and healthcare professionals a range of options for treatment such as mastectomy, chemotherapy and lumpectomy which makes work easier and guarantees better outcomes (Bhardwaj, 2005). New diagnostic methods provide people with some of the best screening services. New diagnostic methods are designed based on modern high technology. For example, mammograms provide cancer screening of high quality and their level of effectiveness is higher than the detection methods applied previously. New methods of diagnosis have the advantage of speed. For example cancer tests can be done quickly and with lesser complications. Patients can also go through the diagnosis process without discomfort (Kasahara & Tsukada, 2004). For the NHS and healthcare, new methods of diagnosis can help to reduce the time wasted on trying to diagnose patients. It can also reduce the costs used for diagnosis processes and save some resources that go to waste due to delayed and ineffective diagnosis. Diagnosis becomes easier and more accurate when new and advanced methods are applied. Apart from saving time, the accuracy improves faith in modern healthcare and more people can trust in health services. New methods also make possible, delicate operations that hitherto, were risky and complicated. For example, today several imaging methods make it possible for doctors and technicians to do an examination on the anatomy of a patient without the use of invasive procedures to help in the diagnosis process. The NHS will succeed in its role of helping to manage the health of the population and reduce the incidences of death from cancer that is not diagnosed early enough (Emole, 2012). Consequently, there would be a reduction in the funds and other resources used for the treatment and management of cancer cases. Major Challenges for the Future Although many advances have been achieved in the modern day, there is much that can be done to offset the challenges that still exist in the diagnosis of cancer. Researchers have to look into methods of getting better techniques and equipment that will surpass the sophistication levels of those in use today and bring better outcomes. There is need to improve on the diagnosis of cancer so that the disease is completely defeated. Although cancer tumour markers have been trusted for cancer diagnosis, tumour marker levels only are inadequate for cancer diagnosis because it can show the wrong elevation especially when the conditions are not plastic because most tumour markers are proteins that are expressed excessively not just by cancer cells but by ordinary tissues as well (Collins & Workman, 2006). For example, apart from ovarian cancer, CA-125 is elevated in areas like endometriosis and non-malignant ascites. Some cancer biomarkers can be elevated in over one cancer type and in the process they reduce the precision of diagnosis. For example, elevated CEA levels exist in multiple malignancies that have their origin in the intestines. In addition, several markers have a number of cross-reacting epitopes that are shared with ordinary tissue products and this result in errors in the estimation of their quantities (Ludwig & Weinstein, 2005). There is need to improve new biomarkers found in serum that compensate for the shortcomings of conventional tumour markers. The improvements should be in terms of the specificity of organs and sensitivity to detection early in the lifecycle of the disease. The proteomics assay, more so, that which is based on SELDI and the assay for gene expression are believed to be suitable tools for use in the invention of new biomarkers (Emole, 2012). There is need for the development of new markers that can reflect metastasis and aggravation of tumours. Unlike phenotypic biomarkers, suppressor genes or oncogenes are non-specific in somatic cells that have cancer, despite earlier expectations and they may not become very useful in the routine diagnosis of cancer. Researchers will need to take up the challenge of evaluating studies on suppressor gene silencing due to the methylation of microsatellite instability and the promoter areas (Collins & Workman, 2006). They should be evaluated to find out if they can become possible markers to many different cancers. Conclusion Cancer is among the leading killer diseases in the world today. Due to its prevalence around the world, researchers and doctors have developed several methods of diagnosis that keep evolving through the years. Today, new and more effective diagnostic methods are being developed to replace the old and less effective ones. In the last few decades, the diagnosis of cancer has moved through various methods to where it is now. Diagnosis has been done using the Pap test, sampling methods applied in pathological examination, specimen examination, molecular techniques, molecular diagnostic and bio markers among others. The diagnosis of cancer continues to evolve and more advanced and sophisticated methods such as imaging and laboratory techniques are still being developed. Newly developed technologies work alongside or totally replace certain conventional methods. The intelligent surgical knife or iKnife is an example of emerging technology. Another one is the telomeric repeat. Pharmacogenomic testing happens to be the most effective method for routine diagnosis. Imaging technologies through the use of different platforms have advanced considerably with the help of computer-aided technologies. New diagnostic methods for cancer detection hold many benefits for cancer patients, healthcare and NHS. If cancers are detected in their early stages and in good time, the number of people who lose their lives to the disease would significantly be reduced and successful treatment cases would increase tremendously and less people would suffer disability due to cancer related causes. For the NHS and healthcare, new methods of diagnosis can help to reduce the time wasted on trying to diagnose patients. It can also reduce the costs used for diagnosis processes and save some resources that go to waste due to delayed and ineffective diagnosis. The challenges of the future lie in the fact that there is need to completely defeat cancer. Available diagnostic methods need to be improved as much as possible and new one discovered which will help in effective early detection and diagnosis. Bibliography Bhardwaj, J.R. 2005. Recent Advances in Diagnosis of Cancer. Med J Armed Forces India, 61(2): 112–114. Collins I, Workman P. 2006. New approaches to molecular cancer therapeutics. Nature Chemical Biology, 2 (12). Emole, J. 2012. Cancer Diagnosis and Treatment: An Overview for the General Practitioner, Primary Care at a Glance - Hot Topics and New Insights, Dr. Oreste Capelli (Ed.). [Online] Available from: http://www.intechopen.com/books/primary-care-at-a-glance-hot-topics-and-newinsights/cancer-diagnosis-and-therapeutics-an-overview-for-the-general-practitioner. Retrieved 20 April 2017. Kasahara, Y. & Tsukada, Y. 2004. New Insights and Future Advances in Cancer Diagnostics: Limitations of Conventional Tumor markers, pp. 15-23. In Nakamura R.M., Grody W.W., Wu J.T, & Nagle, R.B., 2004. Humana Press. Ludwig JA, Weinstein JN. 2005. Biomarkers in cancer staging, prognosis and selection. Nature Reviews Cancer 5: 845-857. Read More