Introduction
Renal cell carcinoma (RCC) accounts for approximately 4% of cancers and 2% of cancer mortality in the United States. Historically, most patients presented with advanced-stage disease with clinical symptoms of a palpable mass, hematuria, and flank pain. However, in the last 15 years, renal masses have been increasingly diagnosed as an incidental finding at cross-sectional abdominal imaging. At present, more than 60% of renal cancers are discovered in asymptomatic patients undergoing evaluation for unrelated conditions.
Surgical resection is the standard treatment for RCC. Radical nephrectomy and partial nephrectomy (PN: nephron-sparing surgery) are the most used techniques, depending mainly on the tumor size. Thermal ablative techniques (cryoablation, radiofrequency, or microwave ablation) are promising alternative treatments for non-surgical candidates with small renal tumors.
Embolotherapy for renal tumors has been used since the 1970s for symptomatic hematuria, palliation, or preoperative infarction of renal tumors. The evolution of the endovascular techniques, as well as the refinement of angiographic technology, allows a more accurate and safe embolization. As a consequence, embolotherapy for renal cancer has also evolved and expanded its indications.
State-of-the-art embolization in renal cancer is indicated in three clinical scenarios: preoperative, in selected cases of radical or PN; postoperative, in cases of vascular injuries and/or hemorrhage following PN and as a palliative treatment.
This chapter reviews basic concept of renal tumor embolization as well as its indication and clinical role in the modern therapeutic approach of RCC.
Basic concepts
The interventional oncologist (IO) should not only commit on the technique of renal embolization but also in the oncology care of the patient, as a member of the multidisciplinary care group. Clinical consultation, pretherapeutic patient evaluation, as well as postembolization care and patient follow-up are mandatory for good clinical practice.
Before performing the renal embolization a thorough clinical and imaging workup of the patient is mandatory. At consultation the IO must know the patient's clinical history and laboratory tests – mainly platelets, coagulation, and renal function. It is also important to be familiar with the patient's medication and to carefully review the patient's images for a better planning of the embolization. Indeed, most patients referred for embolization for renal cancer are studied by contrast-enhanced multiple detector computed tomography (CT) or magnetic resonance (MR) scans where not only the tumor but also the supplying vessels are depicted.