Aim: to carry out a comparative analysis of treatment results of patients with renal tumors who were undergone to nephron-sparing surgery, depending on the type of temporary and definite hemostasis.
Materials and methods: a total of 163 laparoscopic partial nephrectomies were performed by single surgeon from January 2015 to July 2018. The comparative analysis of treatment results of patients with renal tumors based on following parameters: tumor stage, features of the tumor site, the duration of surgery, the amount of blood loss, complications rate and grade as well as functional and oncological outcomes, depending on the type of temporary and definite hemostasis, was conducted. For preoperative planning the generally accepted nephrometric scale R.E.N.A.L. was used as well as 3D-reconstruction of the tumor.
Results: Of the 163 patients, 64 were women (39.3%). The mean age of patients was 56.7±11.1 (25–80 years). A clinical stage T1a, T1b, T2 and T3a was diagnosed in 77, 20, 2 and 64 cases, respectively. The average tumor size was 34.8±1.1 (11–78 mm). The mean operative time was 84.5±32.2 min (30–180). Laparoscopic transperitoneal access was used in 90 patients (55.21%), retroperitoneoscopic approach was chosen in 73 cases (44.79%). The tumor had exophytic growth in 110 cases (67.5%) and in 53 cases it was endophytic (32.5%), while in 59 cases it localized in renal sinus (36.2%). The operative time was significantly shorter in the Group of zero ischemia (72.2±29.02 [p<0.001]) and bipolar coagulation of the tumor bed (60.8±31.7 [p<0.001]). The mean volume of blood loss was 160.8±142.7 ml (30–900). A GFR calculated by the MDRD equation (mean level was 75.7 ml/min/1.73 m2) on the next day and 6 months after surgery showed a slight decrease in group of zero ischemia, compared to other groups: next day and 6 months after surgery it was 72.8±21.6 (p<0.001) and 72.01±16.6 (p=0.025), respectively. A simple enucleation was performed in 41 cases, while enucleoresection was done in 70 cases. A collection system was opened in 22 cases (13.5%±9.8). The suturing and clipping were performed in 20 and 2 patients, respectively. In 2 cases a stenting was performed. In 2 cases there was hemoglobin drop requiring blood transfusion (1.2%±3). An embolization due to refractory bleeding was required in 3 cases (1.8%±3.7). There was no conversion to open surgery or nephrectomy. Of the 163 tumors, a malignancy was diagnosed in 151 (92.6%±7.5) cases. There was no positive surgical margin and recurrence of the tumor.
Conclusion: Laparoscopic partial nephrectomy can be successfully performed under zero ischemia. The intervention without clamping of renal blood vessels contributes to significant preservation of the renal function.

Keywords: zero ischemia, nephron-sparing surgery, renal cell cancer, laparoscopic partial nephrectomy