The purpose of this study is to evaluate the feasibility, safety and efficiency of zero ischemia laparoscopic microwave ablation-assisted enucleation in comparison with conventional laparoscopic partial nephrectomy in the treatment of T1a renal cell carcinoma.

Microwave ablation has been widely used in the minimally-invasive treatment of renal tumors. Recently, a technique of laparoscopic microwave ablation-assisted renal tumor enucleation was developed, but the experience was preliminary. This study aims to evaluate the feasibility, safety and efficiency of this technique, particularly its role in the preservation of renal function, in comparison with conventional laparoscopic partial nephrectomy.

Inclusion Criteria:

• patients with sporadic, unilateral, newly diagnosed T1a presumed renal cell carcinoma
• exophytic cancer
• distance from the hilar renal vessels and urinary collecting system >= 1cm
• patients with normal contralateral renal function (differential renal function of >40% as determined by renal scintigraphy)
• patients giving consent to the participation in the current clinical trial

Exclusion Criteria:

• patients with a history of other renal diseases, such as urinary lithiasis
• patients with a history of renal surgery