Synchronous liver metastases represent about 10 % of liver metastases from kidney cancer. The subset of patients with potentially surgically resectable primary RCC and resectable liver metastases (2–5 %) are candidates to nephrectomy and liver resection. Candidates include patients who initially present with primary RCC and both solitary or multiple resectable liver metastases. Primary tumor and liver metastases may be resected during the same operation or through staged procedures. The most frequent surgical strategy is the second one, while simultaneous nephrectomy and hepatic resection are uncommonly performed during a combined procedure.

Sakaguchi et al. in 1992 demonstrated the feasibility of simultaneous liver resection and nephrectomy for a large RCC with caval thrombus [24]. The main problem to deal with during combined procedure is that liver resection and nephrectomy need conflicting hemodynamic techniques: during nephrectomy, a normovolemic or hypervolemic state is preferred to supply the contralateral kidney with adequate volume, therefore maximizing renal plasma flow to the remnant kidney. By contrast, relative hypovolemia is desired during hepatic resection (low central venous pressure technique) to limit blood loss during parenchymal transection phase of the operation. Anyway, in patients needing caval thrombectomy, hypoperfusion is especially dangerous because of an increased risk of thrombosis [25].

In the most series, the most frequent indication to combined renal and hepatic surgery is instead locally advanced renal cell carcinoma. Outcome of combined procedures is reported only in few limited series from literature [26, 27]; therefore, indications, perioperative management, and postoperative outcomes for simultaneous liver and kidney resection remain poorly defined. In a recent single-center study, Yezhelyev et al. [25] analyzed outcome of 20 patients who underwent synchronous hepatic and renal resection. To optimize perioperative fluid management, hepatectomy was performed before nephrectomy whenever possible. This strategy allowed maintenance of a low central venous pressure (CVP) technique during hepatic parenchymal transection, followed by fluid repletion before and during nephrectomy. Low central venous pressure was maintained as long as adequate urine output of 25 mL/h and systolic blood pressure of 90 mmHg were preserved during transection of liver parenchyma. At the conclusion of the liver resection, crystalloids were administered to achieve a relative hypervolemic state for optimal kidney resection. In this series, 50 % of patients developed major postoperative complications, and postoperative mortality was 5 %. Pulmonary complications were among the most common in the postoperative period (30 %), followed by intra-abdominal (15 %) and surgical site infections (15 %).

Nephrectomy associated with liver resection can therefore be offered to carefully selected patients with synchronous neoplasms of the liver and kidney in centers with high volume of liver and kidney resection. Because of the low number of study about simultaneous hepatic and renal resection, indications of this procedure are still not codificated.

In patients with unresectable synchronous liver metastases, cytoreductive nephrectomy before systemic therapy is recommended. Many randomized clinical studies show that cytoreductive surgery in association with systemic therapy provides a significant survival benefit compared with systemic therapy alone for patients with metastatic RCC [28]. The European Organization for Research and Treatment of Cancer reported a trial where patients with metastatic RCC were randomized to treatment with INF-alpha or INF-alpha plus radical nephrectomy. In the group submitted to radical nephrectomy, the overall survival was 17 months compared to a survival of 7 months reported for patients without nephrectomy [29]. Cytoreductive surgery of primary tumor has been for decades the gold standard treatment for metastatic RCC because spontaneous regression of metastases was expected upon primary cancer removal. Furthermore, surgical resection of large symptomatic cancer may have a significant palliative effect even in terms of quality of life.

Surgical option includes radical nephrectomy and nephron-sparing surgery. A radical nephrectomy requires proximal ligation of the renal artery and vein and removal of the kidney with Gerota fascia, ipsilateral adrenal gland, and regional lymph nodes. Radical nephrectomy is the preferred treatment for tumors extending into the inferior vena cava. Nephron-sparing surgery was originally indicated only if a radical nephrectomy would have rendered patient functionally anephric, necessitating dialysis. It was also indicated in patients with hereditary forms of RCC who may have multiple tumors and in patients with a unilateral tumor and functioning contralateral kidney affected by renal artery stenosis, hydronephrosis, chronic pyelonephritis, reflux, kidney stones, or systemic conditions such as hypertension or diabetes [30]. However, nephron-sparing surgery has been used increasingly in patients with a normal contralateral kidney, with long-term outcomes comparable to radical nephrectomy [31]. The additional benefits of nephrectomy and nephron-sparing surgery include improved performance status, elimination of paraneoplastic syndromes, and eradication of the source of new metastases. Many series in literature showed that survival in patients with metastatic kidney cancer underwent nephron-sparing surgery of the primary tumor and patients underwent radical nephrectomy was comparable [32].