The oncologic outcomes of nephron sparing surgery in treatment of renal cortical tumors

Renal cell carsinoma is the most common malignant tumor of the kidney and constitutes %2-3 of all adult tumors. It is the third most common malignancy of the urinary tract and has the highest mortality rate of the genitourinary cancers. The widespread use of modern imaging techniques has led to an increase in diagnosis of renal incidentalomas ; that are tumours that tend to be smaller in size, earlier in stage and lower grade. Therefore the use of nephron sparing surgery has increased for treatment of the renal cortical tumors. The objective of our study was to evaluate the clinical and oncological outcomes of patients who underwent nephron sparing surgery for renal tumors in our clinic. Data of 90 patients who underwent nephron sparing surgery at Gazi University School of Medicine Department of Urology between June 2006 and March 2013 were investigated retrospectively. The patients who were included in the study were 54 (%60) males and 36 (%40) females with a mean age of were 54,02 ± 10,33 years. Of the patients 65 (72.8%) and 25 (27.2%) underwent open and laparoscopic partial nephrectomy, respectively. Tumor was located in right, left and both kidneys in 50(55.6%), 38(42.2%) and 2 (2.2%) patients , respectively. 11 patients (12.2%) had a solitary kidney and 13 patients (14.4%) had multiple tumor in their kidneys. Mean tumor size was 3.65 ± 1.8 cm. 32 (35.6%), 32 (35.6%) and 22 (24.4%) patients had tumor in lower, middle and upper of the kidney. The average preoperative hemoglobin and creatinine values were 14.02 ± 1.59 g / dl and 0.99 ± 0.36 mg / dl and the postoperative values were 12.21 ± 1.86 g / dl and 1.17 ± 0 , 8 mg / dl, respectively (p<0,001). Mean preoperative and postoperative e-GFR values were 78.12 ± 22.8 and 74.59 ± 26.98 ml/dk/1,73 m² respectively (p=0,12). Mean operation time was 137,48 ± 31,61 minutes and ischemia time was 24,91 ± 9,07 minutes. PADUA scores were calculated in 47 patients. The average of PADUA score was 8.02 ± 1.75. In the laparoscopic partial group PADUA score was 6.71 ± 0.99 and open partial group had 8.58 ± 1.71 PADUA score(p<0,001). Of the 90 patients, 18 (%20) had pathologically confirmed benign lesions, clear cell RCC in 49 (54,4%), papillary type of RCC in 8 (8,9%), chromophobe cell RCC in 8 (8,9%), unclassified type of RCC in 6 (6,6%), transitional cell carcinoma in 1 (1,1%). The pathological stage of patients were T1a in 54 (76%) cases, T1b in 12 (16,9%), T2 in 4 (5,6%), T3 in 1(1,4%). The grade of tumors were Fuhrman grade 1 in 12 (16,9%) patients, grade 2 in 36 (50,7%), grade 3 in 21 (29,5%) and grade 4 in 2 (2,81%). 9 (10%) patients had positive surgical margins. In patients with positive surgical margins, one patient developed local recurrence and metastasis was detected in 1 patient. Average follow-up time was 34.1 ± 21.65 months. Of the 90 patients, 4 (5,5%) had local recurrence, 2 (2,7%) had metastasis and 4 (4,4%) died. 2 patients who had local recurrence had multiple localized tumors. Radiofrequency ablation treatment applied in 2 patients with local recurrence, radical nephrectomy was performed in 1 patient. In 72 patients with pathologically confirmed malignant tumor; overall, cancer specific and recurrence-free survival was 97,2%, 98,6% and 88,8% ,respectively. Key words: Renal cell carcinoma, nephron-sparing surgery, survival