Cancer cells can spread from the kidney to other parts of the body and develop into a new tumour. The new tumour is called a metastasis, or secondary tumour. If more than one tumour develops in another part of the body, they are called metastases.
Understanding how a type of cancer usually grows and spreads helps your healthcare team plan your treatment and future care. If kidney cancer spreads, it is most likely to spread throughout the kidney. Then it can spread through the fibrous tissue covering the kidney (called the renal capsule) and into the fat around the kidney. Kidney cancer can then spread through the fibrous tissue covering the fat around the kidney (called Gerota’s fascia).
If kidney cancer spreads outside of the kidney, it can spread to the following:
Very rarely, kidney metastasis can disappear without any treatment. This is called a spontaneous regression. But the metastasis usually comes back, or recurs, where it disappeared. It often comes back within a few months.
Spontaneous regression sometimes happens after doctors remove a kidney with advanced cancer to help relieve pain or bleeding. This doesn’t happen very often, so surgery is not done to try to bring about a spontaneous regression.