Management of adverse events of targeted therapies in normal and special patients with metastatic renal cell carcinoma

Treatment options for metastatic renal cell carcinoma (mRCC) have evolved very rapidly, as reflected by the approval of the many drugs that have shown efficacy in phase III studies. Approved drugs include tyrosine kinase inhibitors (TKI) such as sunitinib, sorafenib and pazopanib, vascular endothelial growth factor inhibitors such as bevacizumab, and mammalian target of rapamycin (mTOR) inhibitors such as temsirolimus and everolimus. These biological agents have toxicity profiles that differ from those accompanying current chemotherapeutic agents, but their novelty leads to a lack of exhaustive clinical data regarding related adverse events (AEs), whose symptoms may overlap with those of the chronic illnesses of patients with mRCC such as hypertension, hyperglycemia, and pneumonitis. Hypertension, hypothyroidism, hand-foot syndrome, and fatigue are AEs frequently associated with TKIs; whereas immunosuppression, stomatitis, metabolic alterations, and non-infectious pneumonitis are AEs of mTOR inhibitors. Recommendations for treating these adverse events in patients with mRCC are usually the same as those for the general population. Mild to moderate toxicities may be managed with supportive and pharmacologic interventions, but higher-grade toxicities usually require external specialist consultation, dose reductions, and treatment interruption or discontinuation. Some groups of patients with mRCC, such as frail, elderly patients, and patients with renal or liver dysfunction, require special management of AEs.