Cancer precursor lesions and early detection of lung cancer than chest imaging, the need for early lung cancer diagnostic test checks the following:
Early lung cancer diagnostic test 1. bronchoscopy current widespread use of bronchoscopy of normal tissue and precancerous lesions, low resolution, the diagnostic positive rate was only about 37%, and fluorescence bronchoscopy (LIFE) for early lung cancer The positive rate of diagnosis of 75% or more, LIFE by normal tissues, precancerous lesions and new biological differences between the spontaneous fluorescence to detect and locate new biological epithelium.
Early lung cancer diagnostic tests 2. Cytology by sputum smear method, bronchoscopy brush biopsy or bronchoalveolar lavage, biopsy, etc. to obtain cells for cytological screening, there are 3 methods: Computer Aided sputum cytology image analysis; transformed epithelial cells of the immune staining; PCR-based cancer gene mutations. Sputum smears found that specimens of lung cancer after 74% of malignancy associated changes can be detected, and 12 months before clinical diagnosis can be detected or earlier; cytology diagnosis of central lung cancer is the most valuable One way to find a part of cytology lack of obvious symptoms and chest X ray nor the performance of early lung cancer lesions.
Check in early diagnosis of lung cancer 3. Chest imaging diagnosis, chest CT and magnetic resonance imaging can help the diagnosis and staging of lung cancer, precancerous lesions, but only the thickness of layers of cells, it is difficult airways in the early lesions found on occurred around the airway atypical adenomatous hyperplasia (AAH) and diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNCH) can thin spiral CT.
(1) early chest X-ray signs: lesion diameter 2.0em less, according to its original morphological features, is broadly divided into three types: nodular type, patch type, hollow type.
(2) High-resolution CT slices of early signs: According to the density of ground-glass density, divided into solid nodules and high-density nodules. Ground-glass density shadow in the high-resolution CT (HRCT) lung density on the performance slightly increased, but the film still shows blood vessels and bronchi. Limitations of ground-glass density shadow can be atypical adenomatous hyperplasia and early-stage lung performance.
Check in early diagnosis of lung cancer 4. Morphometric analysis and DNA content determination by computer image analysis system quantitative determination of tissue sections or cell smears of morphological changes, combined with DNA content determination to judge, to overcome the microscope and when the pathologist's subjective differences between different observers, and improve lung cancer before the disease, diagnosis and differential diagnosis of lung cancer the accuracy and reliability.
Check in early diagnosis of lung cancer 5. Lung cancer gene checks oncogenes and tumor suppressor genes associated with control of cell growth and differentiation in lung precancerous lesions and early lung cancer, may have related to the expression of oncogenes and tumor suppressor gene abnormalities.
(1) myc oncogene: To study the poorly differentiated lung epithelial cells around the cancer gene found in the increased expression of myc and ras.
(2) Kr, gene: is to determine the genetic susceptibility of lung cancer, known as the pulmonary adenoma susceptibility gene.
(3) bcl-2: the signal by suppressing apoptosis plays a role in tumorigenesis.
(4) tumor suppressor gene p53: may promote tumor angiogenesis plays an important role.
(5) tumor suppressor gene p16.
(6) Rb: Early lung cancer can be used as an important basis for classification.
Others include FHIT (fragilehistidinetriad) precancerous lesions of the molecular markers, anti-apoptotic protein AKT, CFR-l/PAM-l receptor, CD44 and so on.