Radiofrequency ablation (RFA) is an effective therapeutic intervention for a variety of neoplastic lesions. Many of these procedures are conducted with patients under general anesthesia. Although RFA is associated with infrequent complications, it is not without risk. Injury to adjacent normal structures is a major concern during RFA of cancerous lesions. Unintended injury to normal adrenal tissue during RFA of adrenal tumors can lead to hypertensive crisis, a potentially catastrophic complication. Hemodynamic consequences of RFA of primary or metastatic adrenal masses have not been reported. We report a case of hypertensive crisis (249/140 mm Hg), tachycardia, and ventricular arrhythmia in an 82-yr-old woman undergoing RFA of renal cell carcinoma metastatic to the adrenal gland. Anesthesiologists should be aware of this potentially catastrophic complication. Direct-acting vasodilators and short-acting β1-adrenergic antagonists should be immediately available, and intraarterial blood pressure monitoring should be seriously considered when providing care for patients undergoing RFA of an adrenal mass.