What are the methods for diagnosing early lung cancer

The incidence of lung cancer in my country is increasing year by year. Since the early symptoms are not obvious, many patients are already in the middle or late stages when they seek medical treatment, which seriously affects the prognosis. In recent years, the early diagnosis technology of lung cancer has been continuously improved. This article describes several early diagnosis methods of lung cancer.

Sputum cytology

Bronchogenic carcinoma originates from the bronchial mucosal epithelium. During the process of progression from carcinoma in situ to advanced cancer, cancer cells can be excreted from the body with sputum after falling off. Cytological examination of sputum can help detect early lung cancer. The accuracy depends on strict specimen collection (at least 3 times), preservation technology, tumor size, location, and the diagnostic level and experience of the examiner. Sputum cytology is the least invasive diagnostic method. It is low-cost, non-invasive, easy for patients to accept, can detect occult lung cancer, and has a very low risk of death from the examination. It should be the preferred examination method for patients suspected of lung cancer. Sputum cytology is particularly suitable for patients with central lung cancer and patients with hemoptysis. The limitation is that it cannot be located after early lung cancer is detected, the location of the tumor cannot be determined, and the positive rate is low.

Low-dose spiral CT (LDCT)

When using spiral CT scanning, the voltage is set to 140kV, the current is 40mA, the pitch is 10mm, and the breath is held for 20s to complete a scan. The layer thickness is 5mm for reconstruction. Due to the reduced current and low radiation, it is suitable for lung cancer screening. The 5-year survival rate of lung cancer patients discovered by LDCT is 76%. The limitations are low positive detection rate for central lung cancer, high cost, and low sensitivity for detecting nodules smaller than 6mm in the lungs.

PET (Positronemissiontomography, PET)

PET is a new technology that combines imaging examination with cell function detection, which is helpful for qualitative diagnosis of lesions found by chest X-ray and CT examination. PET-CT is a new technology that combines PET with CT, which can obtain morphological and functional information, provide high-resolution and high-contrast tomographic images, and directly evaluate functional and metabolic information, thus improving the specificity and accuracy of diagnosis of malignant tumors.

PET-CT is a new technology that combines PET and CT. It can obtain morphological and functional information and provide high-resolution, high-contrast tomographic images. It can also directly evaluate functional and metabolic information, thereby improving the specificity and accuracy of the diagnosis of malignant tumors.

Laser-induced Fluorescence Endoscope (LIFE)

It is a new type of fiber bronchoscope developed using cell spontaneous fluorescence and computer image analysis technology. It can significantly improve the sensitivity of bronchoscope in early localization diagnosis of lung cancer and its precancerous lesions, and is a technological breakthrough in ordinary light source bronchoscopy technology (White light bronchoscopy, WLB).

Molecular biology examination

The occurrence of lung cancer is a multi-stage, multi-step pathological process involving multiple genes. In the process of bronchial mucosal epithelial cells evolving into malignant tumors, many molecular biological changes occur. The use of molecular biological methods to detect early genetic and molecular changes in lung cancer makes molecular early diagnosis of lung cancer possible. Commonly used detection techniques include polymerase chain reaction (PCR), reverse transcription polymerase chain reaction (RT-PCR) and gene chip technology, which have been widely used in the detection of sputum, bronchial brushings, bronchoalveolar lavage fluid, tissue biopsy, peripheral blood and bone marrow specimens.