These regimens resulted in substantial toxicity, including patient deaths, along with early and encouraging therapeutic results. Unfortunately, the initial encouraging results have not been consistently observed. Efforts have now been directed at selectively manipulating the immune-enhancing features of the treatment, with lessening of the toxic effects. In several recent studies, lower doses of IL-2 without the cellular components have resulted in favorable results and lower toxicity. Although the drug is approved for the management of patients with metastatic renal cell carcinoma by the FDA, its use should be restricted to patients who can tolerate the side-effect profile and have acceptable cardiac, renal, pulmonary, and hepatic function.
Investigational therapies continue to be studied for renal cell carcinoma.
Although all of these approaches have a scientific preclinical rationale, none, unfortunately, can be considered as having been shown to be effective. The sobering fact remains that nearly 50 percent of all patients diagnosed with renal cell carcinoma die of their disease within five years of diagnosis, and a substantial proportion still present with advanced stages of cancer spread.