The lung is the most common site of distant metastasis from kidney cancer. Domestic statistics show that nearly half of patients with initially diagnosed metastatic kidney cancer have lung metastases, followed by bone metastases and liver metastases (Figure 1).
Figure 1. Incidence of metastases to different organs in 1975 patients with primary metastatic kidney cancer in 23 hospitals in China (August 2007 to October 2008)
Most patients with lung metastases from kidney cancer do not have obvious clinical symptoms, and metastatic lesions are usually detected by chest radiography and chest CT. Some patients with lung metastases near larger bronchi may have clinical symptoms such as persistent cough and hemoptysis.
Pulmonary metastases from kidney cancer are mainly diagnosed by CT of the lungs. The typical CT of pulmonary metastases is a diffuse distribution of multiple small nodules in both lungs, especially in the outer third of the lung or under the pleura, and the size of the nodules can range from a few millimeters to several centimeters.
Patients with kidney cancer are often afraid of tumor metastasis, believing that once it metastasizes, they lose hope for survival, but this is not the case. There are reports showing that patients with lung metastases can have a 5-year survival rate of 60% after undergoing resection of the metastases. In addition, the prognosis of kidney cancer patients with lung metastases is generally better than that of patients with liver metastases and bone metastases. About one-third of patients who have undergone lung metastasectomy are clinically likely to remain tumor-free for a long time; however, most patients develop new metastases months to years after surgery.
Therefore, systemic systemic therapy remains the primary treatment modality for lung metastases from kidney cancer. The main systemic therapies currently available include targeted therapies and novel immunotherapies, which can significantly extend the overall survival time of patients.
Related reading: