**3. Results**

We retrospectively reviewed the records of 57 patients who underwent NSS at our institu‐ tion from 1994 to 2011. The table 1 describes the clinical and pathological features of 57 pa‐ tients operated at our institution. All patients were carefully evaluated to exclude the presence of distant metastases. Preoperative evaluation included: ultrasonography of the kidney, CT of the abdomen and chest X-ray in all patients. Renal function was assessed by measuring serum creatinine level and creatinine clearance.

The mean follow-up was 70.1 months (range: 10-157 months). Out of the 57 patients 35 (61.4%) were male and 22 (38.6%) were female. The median patient age was 53.1 years (range: 37-68 years). Left side tumor was detected in 34 (59.6%) cases and right side in 23 (40.4 %) cases. The tumor was located in the upper pole in 21 (36.8 %), in the mid kidney in 7 (12.2 %) and in the lower pole in 29 (51%) patients. Tumors were located peripherally in 46 (80.7%) cases and the central tumor location was detected in 11 (19.3%) cases. The peripheral location was defined as: peripherally located and enveloped by cortical parenchyma tumor, without extension into the renal sinus. At the diagnosis 53 (92.9 %) tumors were detected incidentally and 4 (7.1%) were associated with microscopic haematuria. The NSS was per‐ formed for absolute indications in 5 (8.7%) and for relative indications in 11 (19.9%) cases. 41 (71.9%) patients underwent NSS for elective indications.

renal capsule was performed 2 to 3 mm away from the tumor margin. The renal pedicle was isolated completely and the renal artery was clamped just before beginning the incision on the renal capsule. The venous clamping was not used in any case. For diminishing the out‐ comes of renal ischemia vigorous hydration, infusion of Mannitol before the arterial clamp‐ ing, and renal hypothermia was adopted in all cases. Tumors were enucleated without a layer of normal parenchyma in 17 cases and enucleoresection was performed in 40 cases. Tumor bed was inspected very carefully on the presense of residual tissue. Intraoperative frozen section of tumor bed was routinely performed. The results of frozen section were negative in all cases. The data of the patients who underwent nephrectomy due to positive margins on the frozen section were not included in the study. The visible bleeding vessels and opened calices were closed using running sutures. Finally, tumor bed was coagulated carefully for haemostatic and partly for oncological reasons. The coagulation was performed by means of diathermy. The parenchymal defect was closed using absorbable interrupted

sutures. In case of large capsular defect it was covered with free peritoneal graft.

**3. Results**

88 Renal Tumor

The stained slides from all tumor specimens were reviewed by urological pathologist. Short‐ ly, the resected kidneys were evaluated macroscopically. The maximal tumor size was meas‐ ured and 1.5 x 2cm tissue samples were taken for further assessment. Specimens were fixed, stained and evaluated by the same pathologist according to conventional technique. Patho‐ logical tumor staging was performed according to the 2002 TNM staging system [11] and nuclear grade was assigned according to the Furhman's grading system [12]. The removed tumor specimen was always inspected by pathologists and the surgical margins were inked. Patients were followed with renal functional tests, chest X-ray, abdominal ultrasound or CT every 3 months during the first year, once in 6 months for the next two years and annually thereafter. In terms of statistical analysis the probability of cumulative and cancer-specific survival was estimated by the Kaplan-Meier method using the whole number of events.

We retrospectively reviewed the records of 57 patients who underwent NSS at our institu‐ tion from 1994 to 2011. The table 1 describes the clinical and pathological features of 57 pa‐ tients operated at our institution. All patients were carefully evaluated to exclude the presence of distant metastases. Preoperative evaluation included: ultrasonography of the kidney, CT of the abdomen and chest X-ray in all patients. Renal function was assessed by

The mean follow-up was 70.1 months (range: 10-157 months). Out of the 57 patients 35 (61.4%) were male and 22 (38.6%) were female. The median patient age was 53.1 years (range: 37-68 years). Left side tumor was detected in 34 (59.6%) cases and right side in 23 (40.4 %) cases. The tumor was located in the upper pole in 21 (36.8 %), in the mid kidney in 7 (12.2 %) and in the lower pole in 29 (51%) patients. Tumors were located peripherally in 46 (80.7%) cases and the central tumor location was detected in 11 (19.3%) cases. The peripheral location was defined as: peripherally located and enveloped by cortical parenchyma tumor,

measuring serum creatinine level and creatinine clearance.


**Table 1.** Clinico-pathological characteristics of 57 patients operated with NSS.

The mean tumour size was 48.1 mm. (range: 41-70 mm.). The mean tumor size in the patients who underwent NSS for elective indications was 44.7 mm. and in the patients who underwent NSS for absolute and relative indications was 65.8 mm (p<0.04). The difference between the lat‐ er two groups was not significant. Fifty three out of 57 tumors were pT1b (92.9 %) and 4 (7.1%) were pT3a. Pathological T3a stage was confirmed by tumor microinvasion into the perirenal fat. The final pathological evaluation did not reveal any case of tumor extension out of the inked area of the surgical specimens. Grade I tumor was diagnosed in 22 (38.6%), Grade 2 in 27 (47,4%) and Grade 3 in 8 (14%) cases. Morphological evaluation revealed 49 (85.9%) clear cell, 5 papillary (8.7%), 2 chromophobe (3.7%) and 1 cystic (1.75%) RCCs.

**4. Discussion**

treatment of RCC [4, 10].

was slightly higher than in radical nephrectomy [8].

tumors in appropriately selected patients [14].

the patients who had NSS [15].

The widespread use of modern radiological modalities substantially changed clinical pre‐ sentation of renal tumors in recent decades. Currently, there is a trend towards the diagnosis of asymptomatic, incidental, smaller lesions at lower stages [1, 3, 10]. The local disease re‐ currence is the major drawback of NSS mostly due to the incomplete resection of the pri‐ mary tumor. In this due radical nephrectomy still remains the gold standard for the

Nephron-Sparing Surgery for the Treatment of Renal Cell Carcinoma 4 to 7 cm in Size

http://dx.doi.org/10.5772/53830

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Improved diagnostic and surgical techniques have led to wider use of NSS. Uzzo RG. and Novick AC. in their review of the results of more than 1800 cases of NSS have showed that the true biological significance of multicentric renal tumors and its implications for NSS re‐ mains to be elucidated [3]. In a prospective, randomized EORTC (European Organisation for Research and Treatment of Cancer) phase 3 study comparing open partial nephrectomy (OPN) with open radical nephrectomy (ORN) in small renal tumors (< 5 cm.) found compa‐ rable oncological results in the both arms [8, 9]. Moreover, excellent 5 and 10 year diseasefree survival rates of 98.5% and 96.7% have been reported after NSS in non-randomized studies [5-7]. These data are now widely accepted. Finally, the recent evidence favoring the NSS over radical nephrectomy in the prevention of chronic kidney disease and possibly linking it to a better overall survival will constitute a strong argument for wider use of NSS. On the other hand, NSS is technically more demanding than RN even for small renal tumors [13]. The previous report of the EORTC 30904 trial revealed that complication rate in NSS

Based on the success of NSS in the tumors of ≤ 4 cm, it has been increasingly used for the treatment of 4-7 cm. tumors in case of a normal contralateral kidney. Leibovich BC. *Et al.* retrospectively compared the results of NSS and radical nephrectomy in the tumors of 4 to 7 cm in size. There were no statistically significant differences in cancer-specific survival and distant metastases-free survival after adjusting for important pathological features. Thus, the authors concluded that the NSS has excellent results for the treatment of 4 to 7 cm renal

Dash A. *et al.* compared the outcomes of the patients who had an elective partial or radi‐ cal nephrectomy for clear cell renal cell carcinoma of 4–7 cm. in size. With the median follow-up of 21 months the authors failed to show that radical nephrectomy was associ‐ ated with a better cancer control than the NSS. In terms of functional results the authors found that the serum creatinine level 3 months after surgery was significantly lower in

Becker F. *et al.* reported the excellent results of NSS performed for elective indications. 69 patients with the tumor size of more than 4 cm. underwent NSS. After a mean follow-up of 6.2 years seven patients (10.1%) have died, none of them due to the tumor-related causes. Tumor recurrence was detected in four patients (5.8%). The 5-year overall survival was 94.9%. The 10-year and 15-year overall survival was 86.7%. Cancer-specific survival was 100% at 5, 10, and 15 years. The authors concluded that the selected patients with localized

The mean duration of renal ischemia was 22 minutes (range: 18-35 mm.). No perioperative mortality and/or serious general complications (myocardial infarction, deep venous throm‐ bosis etc.) have been observed. Postoperative complications occurred in 5 (8.8%) patients in‐ cluding: one (1.7%) postoperative bleeding and 4 (7%) urinary fistulas. The bleeding was observed in peripherally located, large (6 cm. in size) tumor operated for absolute indica‐ tion. Urinary leakage occurred in two patients operated for centrally located (18.1%) and in two (4.2%) peripherially located tumors. This difference was statistically significant in favor of peripherially located tumors (p<0.0001). All patients required a double "J" stenting. Peri‐ renal hematoma was observed in 2 (3.5%) cases but did not need any intervention and re‐ solved spontaneously. Renal functions were stable in all patients during the follow-up period with a median postoperative creatinine level of 0.9 mg/dl (range: 0.7–1.4 mg/dl). The median hospital stay was 6 days (range: 4-15 days).

The tumor has recurred in 6 (10.5%) patients. Of them, local recurrence was detected in 2 (3.5%) and systemic recurrence in 4 (7%) patients. At the end of the follow-up overall surviv‐ al was 85.8%, the disease-free survivals was 88.2 %. Both disease-free and overall survival were significantly better in groups of relative and elective indications as compared with ab‐ solute indication (p=0.014 and p=0.023, respectively) (Figure 1).

**Figure 1.** Cancer-specific survival in the patients with elective, relative and absolute indications for NSS. Elective; Relative; Absolute
