Staging guidelines for kidney cancer are as follows (2.5 cm equals approximately 1 in):
Stage I: Primary tumor is 5 cm or less in greatest dimension and is limited to the kidney, with no lymph node involvement.
Stage II: Primary tumor is larger than 5 cm in greatest dimension and is limited to the kidney, with no lymph node involvement.
Stage III: Primary tumor may extend into major veins or invade adrenal glands or perinephric tissues, but not beyond Gerota's fascia. There may be metastasis in a single lymph node.
Stage IV: Primary tumor invades beyond Gerota's fascia. Metastasis in more than one lymph node. Possible metastasis to distant structures in the body.
Each person's treatment is different and depends on several factors. The location, size, and extent of the tumor have to be considered in addition to the patient's age, general health, and medical history.
The primary treatment for kidney cancer that has not spread to other parts of the body, which is a Stage I, II, or III tumor, is surgical removal of the diseased kidney (nephrectomy). Because most cancers affect only one kidney, the patient can function well on the one remaining. Two types of surgical procedure are used. Radical nephrectomy removes the entire kidney and the surrounding tissue. Sometimes, the lymph nodes surrounding the kidney are also removed. Partial nephrectomy removes only part of the kidney along with the tumor. This procedure is used either when the tumor is very small or when it is not practical to remove the entire kidney. It is not practical to remove a kidney when the patient has only one kidney or when both kidneys have tumors. There is a small (5%) chance of missing some of the cancer. Nephrectomy can also be useful for Stage IV cancers, but alternative surgical procedures such as transarterial angioinfarction may be used.
Radiation therapy, which consists of exposing the cancer cells to high-energy gamma rays from an external source, generally destroys cancer cells with minimal damage to the normal tissue. Side effects are nausea, fatigue, and stomach upsets. These symptoms disappear when the treatment is over. In kidney cancer, radiation therapy has been shown to alleviate pain and bleeding, especially when the cancer is inoperable. However, it has not proven to be of much use in destroying the kidney cancer cells. Therefore radiation therapy is not used very often as a treatment for cancer or as a routine adjuvant to nephrectomy. Radiotherapy, however, is used to manage metastatic kidney cancer.
Treatment of kidney cancer with anti-cancer drugs (chemotherapy) has not produced good results. However, new drugs and new combinations of drugs continue to be tested in clinical trials.
Immunotherapy or immunologic therapy, a form of treatment in which the body's immune system is harnessed to help fight the cancer, is a new mode of therapy that is being tested for kidney cancer. Clinical trials with substances produced by the immune cells (aldesleukin and interferon) have shown some promise in destroying kidney cancer cells. These substances have been approved for use but they can be very toxic and produce severe side effects. The benefits derived from the treatment have to be weighed very carefully against the side effects in each case. Immunotherapy is the most promising systemic therapy for metastatic kidney cancer.
Because kidney cancer is often caught early and sometimes progresses slowly, the chances of a surgical
cure are good. It is also one of the few cancers for which there are well-documented cases of spontaneous remission without therapy.
Lata Cherath Ph.D., Laura Ruth Ph.D., The Gale Group Inc., Gale, Detroit,