Comparison Between Computer Tomography and Conventional X-ray - Research Proposal Example

COMPARISON BETWEEN COMPUTER TOMOGRAPHY AND CONVENTIONAL XRAY IN EARLY DIAGNOSIS OF LUNG CANCER COMPARISON BETWEEN COMPUTER TOMOGRAPHY AND CONVENTIONAL XRAY IN EARLY DIAGNOSIS OF LUNG CANCER ABSTRACT Late diagnosis of lung cancer results to advanced disease with 40% in stage IV, 30% are stage III), the current 5-year survival rate is at 16% making it one of the highest causes of mortality worldwide. The main objective of the study is to compare between computer Tomography and conventional X-ray in early diagnosis of lung cancer. Specific objectives will be to determine the sensitivity, specificity, positive and negative predictive values of computer tomography as compared to conventional X-ray in diagnosis of lung cancer and to determine if the outcome of the study will result to an evidence based clinical diagnostic strategy that will reduce morbidity and mortality from lung cancer Key words; x-ray, computed tomography, lung cancer Background information Lung cancer is the leading cause of death worldwide, causing as many deaths as the next 4 most deadly cancers combined breast, prostate, colon, and pancreas (Jemal, 2010). In economically developed countries, lung cancer is the leading cause of death whereas in developing countries, it is second. (Weinstein, et al., 2010) Effective and efficient screening lung cancer may reduce the risk of death from lung cancer. This can be achieved through provision of rapid sensitive tests for capable of detecting small lesions, which are characteristics of early stage of the disease, provision of available effective treatment and resulting to acceptable death rate and cost of screening especially when it is in correlation with other diseases such as pneumonia (Tang, et al., 2011). For decades, X-ray has been the most common method of lung cancer screening, however, more advanced method like Computer Topography have been invented to improve on the sensitivity of the screening test. A research conducted on high risk population showed statistically reduced risk of cancer mortality as compared to chest X-ray and concluded that the benefits of screening high risks populations for lung cancer with LDCT outweigh harms if screening is implemented in strictly controlled manner (Roberts et al, 2013). Problem statement Significance of the study Despite conventional X ray method having been the most commonly used screening lung cancer worldwide, mortality from Lung cancer due to delayed diagnosis is still high. The conventional X- ray method lacks sensitivity which is a major challenge to efficient and reliable early cancer of the lungs diagnosis. It has resulted to most patients being diagnosed with advanced disease, resulting in a very low 5-year survival. Use of a more sensitive Low dose spiral computer tomography as a strategy to reduce mortality from lung cancer has not been confirmed and needs more evaluations are still underway. Research questions What is the sensitivity, specificity, positive and negative predictive values of computer tomography as compared to conventional X-ray in detection of lung cancer Can you compare and contrast between conventional X-ray and Computer tomography in early diagnosis of lung cancer? Do health providers have an evidence based clinical diagnostic strategy that will reduce morbidity and mortality from lung cancer Objectives General objective To compare between computer tomography and conventional X-ray in early diagnosis of lung cancer Specific objectives To determine the sensitivity, specificity, positive and negative predictive values of computer tomography as compared to conventional X-ray in early detection of lung cancer. To establish an evidence based clinical diagnostic strategy from the study outcome that will reduce morbidity and mortality from lung cancer Materials and methods A rigorous review of journal articles from the past years in English language from Google Scholar and PubMed Diagnosis of Lung cancer Several methods are currently in use and this includes histological characterisation of resected tumours which is based on diagnosis on small biopsies and cytology. Other methods include, chest X-rays, sputum cytology and computer topography among others. However, these diagnostic tests could cause complications (Oken, et al., 2011) Conventional X-ray method Radiography or X-ray is one of the ancient methods of non- destructive testing, where solid objects are penetrated by radiation energy. The thickness and density of the material that X-ray penetrates affects the amount of radiation reaching the detector (Hurt, et al., 2013) Based on emission and absorption of x-rays as they pass through different parts of patients body, of which some of the emitted radiation may be scattered in all the direction. The amount of x-ray absorbed contributes to radiation dose to patients. . During imaging, the exiting X-rays interact with a detection device X-ray film providing two dimensional projection image called radiograph and is record on film. The technique involves taking photographic film of shadow of the object to be viewed. Radiography inspects any material defect, and van locate internal features confirm location of hidden parts in assembly and measure thickness of materials. Examination of X-ray films requires high degree of efficiency in interpretation (Beister, Kolditz & Kalender, 2012) Exposure to the X-rays must be restricted, since a number of protons may be passed to the body during examination and may be cancerous. The method is not efficient since not all information can be obtained from the X- ray beam. X-rays have a radiation diagnostic dose on chest of CT (~8 mSv) 56UV and the radiation produced are energetic and more penetrating. They are not effective at detecting flaws in that are orientated in a plans direction with respect to radiation source. Not effective in detecting de lamination and consumes much time when examining thick samples Biological effects Damage caused by proportion of exposure to dosage may pose health and safety risks not present. In US, the average dosage of body dose per year is 84millirems per year. When absorbed by tissues, they change structure of tissue and causing burns or destruction. Hereditary trait may be passed through generations. Adverse effects include damage to hair follicles, leading to hair loss in the irradiated left thoracic area, skin injury, increased breathing rates inflammation, pneumonitis and fibrosis (McMahon, et al, 2012) Observational studies suggest over diagnosis in detection of lung cancer due to use of x-ray. Patients should be adequately informed to the nature and the magnitude of trade off involved in early detection of cancer (Welch & Black, 2010) Low dose spiral computed tomography scan (LDSCT) Tomography is a procedure used when visualizing selected planes within a patient produce a3D cross sectional images of an object from flat X-ray imaging system. Produces cross sectional images or slices of anatomy as the X-ray source rotates around the inside of the circular opening as the digital detector registers hundreds of cross sectional images from all angles, as the computer reconstructs the inner structural image processing data into complete 3D representation. The image is scanned in successful layers by a narrow beam of X-ray, and the transmission of X-ray proton area across a particular layer are measured by computer, which constructs the picture of the internal structure. Tissue density may be artificially enhanced by intravenous injection of substances containing large atoms. Scanning is done by a narrow beam of X-ray (Bach, et al., 2012) The results are displayed in three ways; A paper record of printout of the absorption coefficients relating to small previous defined volumes of tissues, The system is 100 times sensitive than conventional X-rays and therefore variations in soft tissues of nearly similar density can be displayed. The method offers reliable continuity of sections and in so doing omission of autonomic levels and repeated scanning are prevented. Similar study done to determine whether screening for lung cancer, using regular sputum examination, chest radiography or CT scanning of chest reduces lung cancer mortality concluded that annual low dose CT screening has been associated with reduction in lung cancer mortality in high risk smokers but further data are required on the cost effectiveness of screening and relative harms and benefits of screening across a range of different risk groups and settings (Manser et al, 2011). The effective dose of radiation of LDCT is estimated to be 1.5 mSv per examination, but there is substantial variation in actual clinical practice. However, diagnostic chest CT (~8 mSv) 56 or PET CT (~14 mSv)56-58. The method allows imaging of multiple slices simultaneously in relatively less time . Limitations of Low dose computed Tomography has been associated with higher risk for false positive lung cancer screening than chest radiology (Stanbrook, 2010). Earlier studies suggested that chest radiographs screening may have an over diagnosis rate of roughly 25% .Estimates of harms from such radiation come from several official bodies and commissioned studies, based on dose extrapolations from atomic bombings and also many studies of medical imaging ( Hoop, et al., 2010) Data management and analysis Data extracted from the evaluation report findings, outcome will be analyzed using Microsoft Word and Excel computer software. Qualitative methods will be applied to characterize outcome results of study and a backward step-wise logistic regression will be conducted using SAS to determine factors that hinder cancer of lungs diagnosis Confidentiality was ensued through computer restricted password. The study will be approved by either the UH ethics, NHS or both. Time plan 2014-2015 Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr Concept Paper writing X X Proposal writing/ presentation X X X Sampling & Data collection X X X Analysis X X X Data presentation X X Consultation X X X X X X X X X X X X X Literature search strategy Description of topic Databases used Keywords Alternative spellings, synonyms, phrases to key words/key concepts Description Usefulness of search Limits Applied to the search Number of articles PubMed Google Scholar x-ray, computed tomography, lung cancer N/A Comparison between computed tomography and conventional x-ray in early detection of lung cancer would be an important aspect in radiology The search is useful so as to determine if computed tomography used currently to detect cancer is better than conventional x-ray Search was done in journal articles only from 2010 15 journal articles were used in the research. Critical appraisal 1. Ahmedin J., DVM, Freddie B., Melisa M., Jacques F., Elizabeth W., and David F., Global cancer statistic, 2011. A cancer journal for clinicians, 61(2), pp. 69-90. The review adequately addressed the topic. The article had an appropriate study design. The article was relevant since it came from a follow up from a reference list. The authors ensured quality assessment of the article. The results of the review were also clear. 2. B. de Hoop, D. W, de Boo, H. A Gietema, F. van Hoorn, B. Mearadji, L. Schijf, B. van Ginneken, M. Prokop, C. Schaefer-Prokop, 2010. Computer-aided detection of lung cancer on chest radiographs: effect on observer performance. Radiology 257(2) pp. 532-540 The review adequately addressed the topic. The article had an appropriate study design. The article was relevant since it came from a follow up from a reference list. The authors ensured quality assessment of the article. The results of the review were also clear. 3. Peter B. Bach, Joshua N MIrkin, Thomas K Oliver, Christopher Azzoli, Donald A. Berry, Otis W. Brawley, Tim Byers, Graham A. Colditzt, Michael K. Gould, James R. Jett, Anita L. Sabichi, Rebecca Smith-Bindman, Douglas E. Wood, Amir Qaseem, Frank C. Detterbeck. Benefits and Harms of CT screening for Lung Cancer, 2012. The Journal of the American Medical Association, 307(22), pp. 2418-2429 The study addressed the topic effectively in terms of the population, risk studied and outcomes considered. The authors used appropriate methods to answer their questions. The results had a confidence interval of 95% and fit with the available evidence. 4. Beister Marcel, Kolditz Daniel, and Kalender Willi A. Iterative reconstructionmethods in X-ray CT, 2012, Physica medica, 28(2), pp. 94-108. The review addressed the focused question clearly. The review focused on the question and the authors had researched in the appropriate papers. Relevant studies were included from bibliographic databases. If the results of the review could be combined with other reviews, the results would be similar. 5. Christopher N Hurt, Kirsty Roberts, Trevor K. Rogers, Gareth O. Griffiths, Kerry Hood, Hayley Prout, Annmarie Nelson, Jim Fitzgibbon, Allan Barham, Emma Thomas-Jones, Rhiannon Tudor Edwards, Seow Tien Yeo, William Hamilton, Angela Tod and Richard D Neal, 2013. A feasibility study examining the effect on lung cancer diagnosis of offering a chest x—ray to higher risk patients with chest symptoms: protocol for a randomised control trial. Trials.14 (405) The review adequately addressed the topic. If the results of the review could be combined with other reviews, the results would be similar. The results were precise and could be applied to the local population and also cost effective. 6. Jemal A., Siegel R., Xu J., Ward E., Cancer statistics, 2010, CA Cancer J Clin. 60(5) pp. 277-300. The review focused on the question and the authors had researched in the appropriate papers. Relevant studies were included from bibliographic databases. The authors considered the rigor of the studies they have identified. The results were clear and applied to a local population. 7. Karen L. Tang, Dean T. Eurich, Jasjeet K. Minhas-Sandhu, Thomas J. Marrie and Sumit R. Majumdar, 2011. Incidence, Correlates and Chest Radiographic Yield of New Lung Cancer Diagnosis in 3398 patients with Pneumonia. Arch Intern Med. 171(13) pp. 1193-1198 The review adequately addressed the topic. The article had an appropriate study design. There was no selection or bias which would have compromised the study. Relevant studies were included from bibliographic databases. If the results of the review could be combined with other reviews, the results would be similar. 8. Manser R., Lethaby A., Irving L. B., Stone C., Abramson M. J., Campbell D., 3rd ed., CD 001991, Screening for lung cancer the Cochrane Database of systematic reviews. The review addressed the focused issue and the authors used appropriate methods to answer the questions. There was no selection or bias which would have compromised the study. Relevant studies Bibliographic databases were used to ensure relevance. The results of all included studies were identified. 9. Martin M. Oken, William G. Hocking, Paul A. Kvale, Gerald L. Andriole, Saundra S. Buys, Timothy R. Church, David Crawford, Mona N. Fouad, Claudine Isaacs, Douglas J. Reding, Joel L. Weissfeld, Lance A. Yokochi, Barbara O’Brien, Lawrence R. Regard, Joshua M. Rathmell, Thomas L. Riley, Patrick Wright, Neil Caparaso, Ping Hu, Grant Izmirlian, Paul F. Pinsky, Philip C. Prorok, Barnett S. Kramer, Anthony B. Miller, John K. Gohagan and Christine D. Berg, 2011. Screening by Chest Radiograph and Lung Cancer Motality. The Journal of the American Medical Association. 306(17) pp.1865-1873 The outcome considered from the review clearly focused on the question. The review also indicated that the authors looked for the appropriate sort of papers. The review addressed the focused question clearly. If the results of the review could be combined with other reviews, the results would be similar. The results were precise and could be applied to the local population. Review of the articles was also cost effective. 10. McMahon, P. M., et al., The MGH – HMS Lung Cancer Policy Model: Tobacco Control versus screening, 2012, Risk analysis: an official publication of the Society for Risk Analysis, 32(1), pp.117 – 124. The review clearly focused on the topic in terms of the population studied, outcomes considered, and it tried to detect a beneficial and harmful effect of conventional x-ray and computed tomography. If the results of the review could be combined with other reviews, the results would be similar. 11. Neil W., Schluger, R., Koppaka lung disease in a global content. A call for public health action, 2014, Annals of the American thoracic society, 11(23), pp. 407-416. The review clearly focused on the topic in terms of the population studied, outcomes considered, and it tried to detect a beneficial and harmful effect of conventional x-ray and computed tomography. There was no selection or bias which would have compromised the study. Relevant studies Bibliographic databases were used to ensure relevance. The results of all included studies were identified. 12. Stanbrook, M. B., An intern med. 2010, Earlier studies suggested that chest radiographs screening may have an over diagnosis rate of roughly 25%, 153(4), pp. 2-5. The review adequately addressed the topic. If the results of the review could be combined with other reviews, the results would be similar. The results were precise and could be applied to the local population and also cost effective. 13. Roberts, Heidi, Walker-Dilks, Cindy,Sivjee, Khalil , Yasufuku, Kazuhiro , Hey, Amanda, Lewis, Nancy, 2013. Screening high risk populations for lung cancer’ Guideline recommendation, Journal of thoracic Oncology, 8(10) pp. 1232-1237. The review addressed the focused question clearly. If the results of the review could be combined with other reviews, the results would be similar. The results were precise and could be applied to the local population. Review of the articles was also cost effective. 14. Weinstein, Lauren E., Cipriano, Angela C., Tramontano, Bruce E., Johnson, Jane C., Weeks, and G. Scott Gazelle, 2010, World health org the global burden of disease update, Geneva, WHO. The study addressed the focused topic and authors used appropriate methods to answer their questions. The author accounted for socio-economic factors in the research. Similar results would be achieved if combined with other studies. 15. Welch H. Gilbert, William C. Black, 2010, over diagnosis in Cancer. Journal of the National Cancer Institute. 102(9) pp.605-613 The study addressed the topic effectively in terms of the population, risk studied and outcomes considered. The authors used appropriate methods to answer their questions. The results had a confidence interval of 95% and fit with the available evidence. Bibliography Ahmedin J., DVM, Freddie B., Melisa M., Jacques F., Elizabeth W., and David F., Global cancer statistic, 2011. A cancer journal for clinicians, 61(2), pp. 69-90. Beister Marcel, Kolditz Daniel, and Kalender Willi A. Iterative reconstruction methods in X-ray CT, 2012, Physica medica, 28(2), pp. 94-108. B. de Hoop, D. W, de Boo, H. A Gietema, F. van Hoorn, B. Mearadji, L. Schijf, B. van Ginneken, M. Prokop, C. Schaefer-Prokop, 2010. Computer-aided detection of lung cancer on chest radiographs: effect on observer performance. Radiology 257(2) pp. 532-540 Christopher N Hurt, Kirsty Roberts, Trevor K. Rogers, Gareth O. Griffiths, Kerry Hood, Hayley Prout, Annmarie Nelson, Jim Fitzgibbon, Allan Barham, Emma Thomas-Jones, Rhiannon Tudor Edwards, Seow Tien Yeo, William Hamilton, Angela Tod and Richard D Neal, 2013. A feasibility study examining the effect on lung cancer diagnosis of offering a chest x—ray to higher risk patients with chest symptoms: protocol for a randomised control trial. Trials.14 (405) Jemal A., Siegel R., Xu J., Ward E., Cancer statistics, 2010, CA Cancer J Clin. 60(5) pp. 277-300. Karen L. Tang, Dean T. Eurich, Jasjeet K. Minhas-Sandhu, Thomas J. Marrie and Sumit R. Majumdar, 2011. Incidence, Correlates and Chest Radiographic Yield of New Lung Cancer Diagnosis in 3398 patients with Pneumonia. Arch Intern Med. 171(13) pp. 1193-1198 L. Weissfeld, Lance A. Yokochi, Barbara O’Brien, Lawrence R. Regard, Joshua M. Rathmell, Thomas L. Riley, Patrick Wright, Neil Caparaso, Ping Hu, Grant Izmirlian, Paul F. Pinsky, Philip C. Prorok, Barnett S. Kramer, Anthony B. Miller, John K. Gohagan and Christine D. Berg, 2011. Screening by Chest Radiograph and Lung Cancer Motality. The Journal of the American Medical Association. 306(17) pp.1865-1873 Manser R., Lethaby A., Irving L. B., Stone C., Abramson M. J., Campbell D., 3rd ed., CD 001991,2011, Screening for lung cancer the Cochrane Database of systematic reviews Martin M. Oken, William G. Hocking, Paul A. Kvale, Gerald L. Andriole, Saundra S. Buys, Timothy R. Church, David Crawford, Mona N. Fouad, Claudine Isaacs, Douglas J. Reding, Joel .McMahon, P. M., et al., The MGH – HMS Lung Cancer Policy Model: Tobacco Control versus screening, 2012, Risk analysis: an official publication of the Society for Risk Analysis, 32(1), pp.117 – 124. Neil W., Schluger, R., Koppaka, Lung disease in a global content. A call for public health action, 2014, Annals of the American thoracic society, 11(23), pp. 407-416. Peter B. Bach, Joshua N MIrkin, Thomas K Oliver, Christopher Azzoli, Donald A. Berry, Otis W. Brawley, Tim Byers, Graham A. Colditzt, Michael K. Gould, James R. Jett, Anita L. Sabichi, Rebecca Smith-Bindman, Douglas E. Wood, Amir Qaseem, Frank C. Detterbeck. Benefits and Harms of CT screening for Lung Cancer, 2012. The Journal of the American Medical Association, 307(22), pp. 2418-2429 Roberts, Heidi, Walker-Dilks, Cindy,Sivjee, Khalil , Yasufuku, Kazuhiro , Hey, Amanda, Lewis, Nancy, 2013. Screening high risk populations for lung cancer’ Guideline recommendation, Journal of thoracic Oncology, 8(10) pp. 1232-1237. Stanbrook, M. B., An intern med. 2010, Earlier studies suggested that chest radiographs screening may have an over diagnosis rate of roughly 25%, 153(4), pp. 2-5. Weinstein, Lauren E., Cipriano, Angela C., Tramontano, Bruce E., Johnson, Jane C., Weeks, and G. Scott Gazelle, 2010, World health org the global burden of disease update, Geneva, WHO. Welch H. Gilbert, William C. Black, 2010, over diagnosis in Cancer. 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