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In the last five years, the use of six new drugs for kidney cancer has opened up new options and more complicated issues for treatment decisions. Before the approval of targeted therapies, metastatic renal cell carcinoma was regarded as one of the most difficult cancers to treat, with a very poor prognosis. Now doctors and their patients have much better choices for longevity and quality of life. But there is a difficult trade-off. A complete cure is still not expected. Treatment programs that offer better longevity tend to produce a lower quality of life, due to the side effects of the drugs. Doctors have guidelines for choosing the optimum treatment based on patient age, tumor burden, and individual history. But the patient's personal goals and response to the drugs is perhaps even more important.
The new drug options are as follows, along with their dates of approval for metastatic kidney cancer (most have been in use longer for other indications):
1. Sorafenib (Nexavar), December 2005
2. Sunitinib (Sutent), January 2006
3. Temsirolimus (Torisel), May 2007
4. Bevacizumab (Avastin) plus IFN-alpha (Roferon), August 2009
5. Everolimus (Afinitor), March 2009
6. Pazopanib (Votrient), October 2009
See references for a comprehensive list of side effects for each drug. The targeted therapies are considered less toxic than older chemotherapies, but some patients may find them intolerable. There is considerable variation among patients.
Kidney cancer also varies greatly from one patient to the next. It is slow growing and almost stable in some patients, but aggressive and symptomatic in others. Tumor control may be be preferable to a high remission rate for patients with a low tumor burden, since durable and complete remission is rare. Patients with aggressive tumors may benefit more from aggressive treatment. Chronic treatment is common, and most patients today can expect to receive several targeted therapies in sequence.
The authors report that only a quarter of cancer treatment decisions are based on level 1 evidence, because it is so difficult to get a large number of patients to test every possible combination of therapies.