Mini-flank incision for open partial nephrectomy for renal tumor with Zhongshan score≥8

Abstract

Objective To evaluate the effect and feasibility of mini-flank approach for open partial nephrectomy (MI-OPN) in complex renal tumors with high Zhongshan Score(ZS Score ≥8). Methods Between January 2012 and December 2014, the data from 25 patients with renal tumors, including 18 male and 7 female patients, were retrospectively reviewed.The average age was 50.2 years(range 26-75 years)and the average body mass index was 24.5 kg/m2(range 21.3-30.1 kg/m2). The initial symptom included asymptom in 17 cases, hematuria in 6 cases and other presentation in 2 cases.Bilateral renal tumors were found in 4 cases.Fifteen cases suffered with contralateral urinary stone, renal cyst or hydronephrosis.The preoperative serum creatinine level was 76.9 μmol/L(range 47-132 μmol/L) and the preoperative estimated glomerular filtration rate (eGFR) was 103.8 ml/(min·1.73 m2)(range 36.5-173.9). The ZS Score was 8 in 11 cases, 9 in 3 cases, 10 in 5 cases, 11 in 2 cases, 12 in 2 cases, and 13 in 2 cases.Mean maximum tumor size was 4.9 cm (range 2.5-8.1 cm) in CT scan.The average length of incision was 8.0 cm(7.5-10.0 cm). During the operation, the mass and around normal renal tissue were exposed after opening the Gerota fascia.Along the dorsal of kidney, the renal artery was dissected and clamped.Then, the mass was completely removed along margin of 0.5-1.0 cm normal renal tissue.The vascular end was closed by 3-0 absorbable suture.The entire wound of kidney was U shaped closed by 2-0 absorbable suture.The operative time, ischemia time, estimate blood loss, pathology parameters, operative and short-term (2-3 months) postoperative complications were recorded.Renal function was recorded 2-3 months after operation. Results MI-OPN was successfully performed in 23 cases.Radical nephrectomy was performed in 1 cases due to the tumor invasion into the renal pelvis and ureteropelvic junction.Another radical nephrectomy was performed for suspection of positive margin.Mean operative time was 100.2 min(range 75-150 min), mean warm ischemia time was 28.3 min(range 21-39 min) and mean estimated blood loss was 63.6 ml(range 10-400 ml). Only 1 case accepted blood transfusion.Mean postoperative hospital stay was 6.6 days (range 5-9 days). Postoperative complications were found in 1 patient, who was found the fluid in surgical region and relieved after the drainage. The pathological diagnosis included clear cell carcinoma in 21 cases, papillary carcinoma in 3 cases and chromophobe cell tumor in 1 case. The mean postoperative serum creatinine level was 88.9 μmol/L(range 61-189 μmol/L) and the mean postoperative eGFR was 86.3 ml/(min·1.73 m2)(range 34.0-149.6). There was significant difference between pre and postoperative renal function (P<0.01). During the average follow-up period of 13.7 months (range 6-24 months), no local recurrence or metastasis occurred. Conclusion MI-OPN is an innovation of traditional OPN and suitable for the complex renal tumors with high ZS score. Key words: Kidney neoplasms; Nephron sparing surgery; Mini-incision; Zhongshan score