About 20% to 30% of newly diagnosed kidney cancer cases already have metastases at the time of presentation; 20% to 40% of patients who have undergone radical resection still have distant metastases after surgery. The most common location of metastasis is the lung, followed by lymph nodes, bone, liver, brain, adrenal glands, pancreas, skin, and many other organs.
Figure 1. Incidence of metastases in different organs among patients with metastatic kidney cancer initially diagnosed in 23 hospitals in China (August 2007 to October 2008)
There is no uniform standard treatment plan for metastatic kidney cancer, and the main treatment is a combination.
- Metastasectomy can be considered in case of a single smaller lesion in the lung or a local recurrence in the kidney.
- Bone metastases with severe pain can be treated with radiotherapy and bisphosphonates, and bone metastases causing spinal cord compression or pathologic fractures can be surgically decompressed and strengthened with fixation.
- Liver metastases may be considered for interventional therapy and radiofrequency ablation.
- Patients with brain metastases may try surgery, gamma knife, or whole cranial radiation therapy to reduce neurologic symptoms.
These are all local treatments for metastatic lesions, which can only control localized lesions. Patients also need systemic therapy throughout the body, and the main options now are targeted drug therapy and novel immunotherapy, and systemic therapy can be more effective in controlling kidney cancer cells throughout the body.
Therefore, the only way to get a better overall outcome is to combine local and systemic systemic therapy for different metastases.