LITHUANIAN UNIVERSITY OF HEALTH SCIENCES LUHS LIBRARY REPOSITORY

Radiologinių tyrimo metodų palyginamoji vertė nustatant plaučių vėžio stadiją ir prognozuojant chemoterapijos efektyvumą

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dc.contributor.author Mikalauskas, Vytenis
dc.date.accessioned 2017-08-21T08:06:40Z
dc.date.available 2017-08-21T08:06:40Z
dc.date.issued 2006
dc.identifier.uri http://repository.lsmuni.lt/handle/1/60024
dc.description.abstract 1. INTRODUCTION Lung cancer is the most common malignancy in the world and accounts for 1.09 million new cases with 972 000 deaths per year. In Lithuania too, lung cancer is the most commonly diagnosed cancer in men with nearly 1500 new cases each year. Lung cancer is five times more common in men than in women. At present, most patients who receive an initial diagnosis of lung cancer have advanced stage disease (stage IV – 30.2%), making cure with currently available therapies unlikely. The main prognostic information with regard to survival is associated with the biological characteristics of the primary tumour (histological subtype, aggressiveness, differentiation, etc.), the extent of spread to regional or distant lymph nodes or to the other structures, and the operability of the patient (age, function of residual lung, co-morbidity). Because the outcome is associated with the histological subtype and stage of the lung cancer at the diagnosis, there has been persistent interest in designing and testing various radiological methods for early detection of lung cancer. Chest radiography, computed tomography (CT), magnetic resonance imaging (MRI) can not only identify specific features in lung nodules, but add important information about the localisation, size and extent of the primary tumour (T), detect invasion of major mediastinal structures and chest wall, and locoregional (N) and distal spread of the tumour. Although theoretically features such as nodal shape, density, and margins could help to differentiate benign from malignant lymph nodes, currently the only useful imaging sign is enlargement. The problem with using size as the only criterion for malignant nodal disease is that nodal enlargement may be due to multiple benign causes and that normal-sized nodes may contain microscopic metastasis. Single photon emission computed tomography (SPECT) and positron emission tomography (PET) are modern imaging modalities used in oncology. Those nuclear medicine techniques are based on the evaluation of certain metabolic characteristics of the primary lesion (cell proliferation, receptor and antigen expression, metabolic activity, transport across cell membrane), and the detection of tumour metastases. Nuclear medicine procedures are also used in predicting clinical response of lung cancer to chemotherapy. Accurate preoperative tumour staging may allow for highly individual prognoses and, accordingly, the determination of individualised therapy. The incorporation of nuclear medicine techniques into routine clinical practice will be an essential step in the clinical management of lung cancer. 2. Aim and Objectives The aim of this study was to assess and compare prognostic value of chest radiography, computed tomography and single photon emission computed in diagnosis and staging of lung cancer using the TNM system, and to evaluate the role of dynamic scintigraphy in predicting chemotherapeutic response. Objectives: 1. To assess and compare the sensitivity, specificity, accuracy, negative and positive predictive values of chest radiography, computed tomography and single photon emission computed tomography in the differentiation of benign and malignant lung nodules. 2. To evaluate and compare the diagnostic value of single photon emission computed tomography and diagnostic bronchoscopy in the differentiation of benign and malignant lung nodules and compare both with histopathological findings. 3. To estimate and compare the sensitivity, specificity, accuracy, negative and positive predictive values of chest radiography and computed tomography in assessment of the primary tumour (T) status. 4. To assess and compare the sensitivity, specificity, accuracy, negative and positive predictive values of chest radiography, computed tomography and single photon emission computed tomography in the determination of locoregional lymph node involvement, to compare obtained results with patomorphologic findings. 5. To evaluate the role of dynamic scintigraphy in predicting chemotherapeutic response and to create a software for assessment of dynamic studies. Scientific Novelty The analysis of different radiological diagnostic methods used in diagnosis and staging of lung cancer is presented in the study. The sensitivity, specificity, accuracy, negative and positive predictive values of chest radiography, computed tomography and single photon emission computed tomography in the differentiation of benign and malignant lung nodules were estimated and compared with bronchoscopy results and histopathological findings. Assessment and comparison of accuracy values of radiologic diagnostic modalities in lung cancer staging was performed. For the first time in Lithuania single photon emission computed tomography for differentiation of lung nodules and determination of lung cancer spread into the mediastinal lymph nodes was introduced into the clinical practice. We were the first in the Baltic States to use one of the newest radiopharmaceuticals – 99mTc-depreotide (99mTc-NeoSpect) in the diagnosis of lung cancer. SPECT with this radiopharmaceutical is used for the scintigraphic differentiation of benign and malignant solitary lung nodules as the sensitivity and diagnostic accuracy compare favourably with the reported for 18F-FDG-PET. At present, 18F-FDG-PET has been advocated as the most sensitive and accurate diagnostic modality for diagnosis and staging of the lung cancer. SPECT with 99mTc-depreotide is recommended for the countries where 18F-FDG-PET is not available. We used SPECT with 99mTc-depreotide not only for the differentiation of benign and malignant solitary lung nodules as it is indicated, but also we were one of the first in the world to use this radiopharmaceutical for staging of the lung cancer. There were no studies performed in Lithuania covering this topic and only very few articles are published in the literature so far. We were not able to find any publications comparing the diagnostic value of chest radiography, computed tomography and single photon emission computed tomography in the lung cancer staging. No studies were performed comparing SPECT and bronchoscopy results in differentiation of benign and malignant lung nodules as well. The original software was created for more accurate prediction of chemotherapeutic response of lung cancer by means of dynamic scintigraphy. Practical Importance We introduced into the clinical practice new imaging techniques: SPECT with 99mTc-depreotide for the diagnosis and staging of the lung cancer and dynamic scintigraphy with 99mTc-tetrafosmin for prediction of chemotherapeutic response. Nuclear medicine offers additional information about metabolic activity of the lung nodule making differentiation between benign and malignant more efficient and also improves the selection of patients for diagnostic thoracotomy. Single photon emission tomography is helpful in assessment of small peripheral lesions when differentiation between benign and malignant lung nodule with other diagnostic modalities is difficult or impossible. The aim of the radionuclide imaging is to achieve better correlation between clinical TNM and pathomorfological TNM in patients with the lung cancer, to help in evaluation of lymph node involvement (to depict present micrometastases in normal-sized lymph nodes and to prove the absence of involvement in enlarged lymph nodes). Lung cancer staging is based on the determination of lymph node involvement. Accurate tumour staging may allow for highly individual prognoses and, accordingly, the determination of individualised therapy. Nuclear medicine imaging techniques help in evaluation of tumour extension and are complementary to anatomical imaging such as computed tomography. Combination of functional and anatomical imaging allows to perform biopsy of involved lymph nodes and guides mediastinoscopy resulting in effective histopathologic examination. Chemotherapy response is dependant on anticancer drug concentration in the tumour cells. Intracellular drug concentration is regulated by multidrug resistance (MDR) gene. 99mTc-tetrafosmin follows the same transport mechanism across the cell membrane as most of the chemotherapy drugs, therefore, seems to be a suitable substrate for detecting MDR in vivo. The original software created in our study is based on the analysis of only two static chest images, which allows estimation of the radiopharmaceutic washout from the tumour cells and effectively saves gamma camera time. Acquisition of those two static chest scintigrams in our study takes only 5 minutes each, while most of the published results are obtained acquiring 32 minutes SPECT images. Dynamic scintigraphy is a useful tool in predicting clinical response of lung cancer to chemotherapy. 2. MATERIALS AND METHODS Patient Population This study was approved by Kaunas Region Independent Biomedical Research Ethics Committee (Protocol No. 98/2003). Seventy-six patients (10 women, 66 men; age range 25-80 y; mean age 59.75 ± 10.3 y) treated in Kaunas medical university hospital from October 2002 through April 2005 were enrolled in this study. Sixty eight (89.5%) patients had histopathologically proven malignant tumours: 44 lung cancers, 1 vaginal and 1 melanoma metastasis, 1 lymphoma, 3 carcinoids and 1 alveolar adenoma. Eight (10.5%) patients had benign lung nodules: 3 cases of granulomas, 2 hamartomas, 1 shvanoma, 1 abscess and 1 patient with fibrotic changes. The study consists of two parts. In the first part 54 (100%) patients were studied with chest radiography, enhanced spiral CT, 99mTc-depreotide or 99mTc-tetrafosmin SPECT and bronchoscopy for suspected lung cancer. All the patients underwent surgery and the final histopathological lung cancer staging (pTNM). SPECT was performed 2-5 days prior to surgery. In the second part, 22 patients with histopathologically proven non-small cell lung cancer (NSCLC) who were to undergo therapeutic chem
dc.language.iso lit
dc.subject RKT
dc.subject Lung cancer
dc.subject Radiology
dc.subject Radiologija
dc.subject Plauciu vezys
dc.subject SPECT
dc.subject Nuclear medicine
dc.subject Branduolinė medicina
dc.title Radiologinių tyrimo metodų palyginamoji vertė nustatant plaučių vėžio stadiją ir prognozuojant chemoterapijos efektyvumą
dc.title.alternative Comparative prognostic value of radiological diagnostic methods in diagnosis and staging of lung cancer and in predicting chemotherapeutic response
dc.type Daktaro disertacija


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