Usually the nature of pleural effusion in lung cancer is often malignant pleural effusion, which belongs to the advanced stage of lung cancer.
Lung cancer may develop pleural metastasis in the advanced stage, which results in malignant pleural effusion, suggesting that the tumor is advanced. If the amount of malignant pleural effusion is excessive, secondary problems such as pulmonary atelectasis may occur. Therefore, when the amount of malignant pleural effusion of lung cancer is large, it should be treated with symptomatic treatment such as fluid extraction.
Of course, there are some patients with pleural effusion complicated by lung cancer, which is not caused by pleural metastasis, but benign pleural effusion. Therefore, the stage of lung cancer is not determined by pleural effusion.
Therefore, for lung cancer with pleural effusion, the nature of pleural effusion should be clarified by puncture first to determine whether pleural metastasis exists, and if it exists, the tumor is in advanced stage.