How is small cell lung cancer diagnosed?

How is small cell lung cancer diagnosed? Recently, many people have been confused about this issue and many people have consulted about this issue. In order to help everyone answer this question and to enable everyone to have a deeper understanding of this disease, today we will talk about how small cell lung cancer is diagnosed.

Pathophysiology

It is generally believed that small cell lung cancer originates from Kulchitsky cells (argentophilic cells) in the bronchial mucosa or glandular epithelium and belongs to APUD (amine precursor uptake decarboxylation) tumors. Some people also believe that it originates from stem cells in the bronchial mucosal epithelium that can differentiate into neuroendocrine. Small cell lung cancer is the least differentiated and most malignant type of lung cancer. It often occurs in the central part of the lung, grows rapidly, and metastasizes early. Under a light microscope, the cancer cells are small and short spindle-shaped or lymphocyte-like, with little cytoplasm and a naked nucleus. Cancer cells are densely arranged in groups, separated by connective tissue, and sometimes cancer cells are arranged in groups around small blood vessels. Electron microscopic observation of ultrastructure shows that the tumor cell cytoplasm contains typical axon-like neuroendocrine granules, but the amount of granules varies, and it has been proven to be related to 5-HT and ACTH. From the immunohistochemical study, the tumor cells are positive for NSE, 5-HT, CgA, and some cases (10%) are positive for Sy, proving that small cell carcinoma has neuroendocrine function. In addition, positive immunohistochemical reactions for CK and EMA were simultaneously found in the same tumor.

Small cell lung cancer may be asymptomatic in the early stages. The most common symptoms at the time of diagnosis are fatigue (80%), cough (70%), shortness of breath (60%), weight loss (55%), pain (40% to 50%), and hemoptysis (25%). Therefore, a preliminary judgment can usually be made clinically based on these symptoms. Lung shadows appear on chest X-rays, and ultrasound can detect tumors, which are low-echo areas with irregular border contours and uneven echoes. CT can detect tumors in the posterior cardiac large blood vessels, mediastinum and other parts that are difficult to detect with X-rays. Magnetic resonance imaging has a high value in judging the nature, location, shape and size of the lesions, as well as the presence or absence of mediastinal and lung metastases.

Concurrent illnesses

Pneumonia, arrhythmia

1. Respiratory complications: Pneumonia and sputum retention are the most common respiratory complications of small cell lung cancer. This is because after surgery, the patient's cough is often restricted due to the pain of the wound, which can easily lead to sputum retention, thus causing lung diseases such as atelectasis.

2. Hemothorax, empyema, and bronchopleural fistula: These are common complications after lung cancer surgery, but the incidence is often relatively low. Once hemothorax occurs, it must be treated in time because the disease is very harmful. Empyema is often caused by bronchial and pulmonary secretions contaminating the chest cavity. Bronchopleural fistula is caused by improper surgical operation, bronchial stump cancer retention, etc.

3. Complications of the cardiovascular system: blood pressure, arrhythmia.

Above we talked about how small cell lung cancer is diagnosed. Now everyone must have a better understanding of this issue.