Stereotactic body radiation therapy could improve disease control in oligometastatic patients with renal cell carcinoma: do we need more evidence?

Renal cell carcinoma (RCC) represents the most common type of kidney tumor and about 70% of the affected patients have clear cell histology tumors (1). Approximately 30% of the patients with RCC will recur locally or distantly after primary treatment and another 30% will present stage IV at diagnosis (2). Usually, distant disease involves lung and liver in around 11–75% and 20–40% of patients, respectively (3-5). Sometimes, in selected RCC patients with few active metastases an oligometastatic state or oligoprogression persist after previous radical resection of primary tumor and administration of systemic therapy (ST).