Andrew C. Novick

LONG-TERM RESULTS OF NEPHRON SPARING SURGERY FOR LOCALIZED RENAL CELL CARCINOMA: 10-YEAR FOLLOWUP

PURPOSE Partial nephrectomy is effective for renal cell carcinoma when preservation of renal function is a concern. We present the 10-year followup of patients treated with nephron sparing surgery at our institution. MATERIALS AND METHODS Partial nephrectomy was performed in 107 patients with localized sporadic renal cell carcinoma before December 1988. Tumors were symptomatic in 73 patients (68%) and indications for surgery were imperative in 96 (90%). Of the patients 42 (39%) had renal insufficiency preoperatively. All patients were followed a minimum of 10 years or until death. RESULTS At the end of the followup interval 32 patients (30%) had no evidence of recurrence, 28 (26%) died of metastatic renal cell carcinoma and 46 (42%) died of unrelated causes. Cancer specific survival was 88.2% at 5 and 73% at 10 years, and was significantly affected by tumor stage, symptoms, tumor laterality and tumor size. Long-term renal function was stable in 52 patients (49%). CONCLUSIONS Partial nephrectomy is effective for localized renal cell carcinoma, providing long-term tumor control with preservation of renal function.

NEPHRON SPARING SURGERY FOR RENAL TUMORS: INDICATIONS, TECHNIQUES AND OUTCOMES

PURPOSE A contemporary review of the indications, techniques and outcomes is presented for nephron sparing approaches to solid renal masses, emphasizing their role for the treatment of renal cell carcinoma. We also reviewed the evolving role of minimally invasive forms of parenchymal sparing renal surgery. MATERIALS AND METHODS MEDLINE and CANCERLIT computerized literature searches, and manual bibliographic reviews were performed to identify published peer reviewed articles pertaining to nephron sparing surgery or partial nephrectomy from 1980 to 2000. Pertinent articles were collated and reviewed. RESULTS Nephron sparing surgery is increasingly being used to treat patients with solid renal lesions. The technical success rate of nephron sparing surgery is excellent, and operative morbidity and mortality are low. For renal cell carcinoma long-term cancer-free survival is comparable to that after radical nephrectomy, particularly for low stage disease. The overall incidence of local recurrence is low at 0% to 10%. For tumors 4 cm. or less local recurrence rates are even less at 0% to 3%. The risk of local recurrence depends primarily on the initial local pathological tumor stage. The reported incidence of multifocal renal cell carcinoma is approximately 15% and it also depends on tumor size, histology and stage. The risk of multifocal disease is low at less than 5% when the maximal diameter of the primary tumor is 4 cm. or less. Recent advances in renal imaging limit the radiographic evaluation necessary when planning complex nephron sparing approaches. Three-dimensional, volume rendered computerized tomography integrates all of the necessary information previously obtained by conventional computerized tomography, angiography, venography and pyelography into a single preoperative test, allowing better operative planning with maximal preservation of unaffected parenchyma in the remnant kidney. Minimally invasive modalities of tumor resection or destruction should be reserved for highly select patients and await improvements in technology, standardization of technique and long-term outcomes data before they may be completely integrated options. CONCLUSIONS Nephron sparing surgery provides effective therapy for patients in whom preservation of renal function is a relevant clinical consideration. The importance of meticulous operative technique for achieving acceptable oncological and functional outcomes is emphasized. Accumulating data in appropriately select patients suggest a long-term functional advantage gained by the maximal preservation of unaffected renal parenchyma without sacrificing cancer control.

NEPHRON SPARING SURGERY FOR LOCALIZED RENAL CELL CARCINOMA: IMPACT OF TUMOR SIZE ON PATIENT SURVIVAL, TUMOR RECURRENCE AND TNM STAGING

PURPOSE We studied the impact of tumor size on patient survival and tumor recurrence following nephron sparing surgery for localized sporadic renal cell carcinoma. In addition, we evaluated the usefulness of the new TNM staging system in which T1 versus T2 tumor status is delineated by tumor size 7 or less versus more than 7 cm., respectively. MATERIALS AND METHODS The results of nephron sparing surgery for localized sporadic renal cell carcinoma in 485 patients treated before 1997 were reviewed. Patients were divided into groups according to tumor size as 1--2.5 or less (142), 2--2.5 to 4.0 (168), 3--more than 4 to 7 (125) and 4--more than 7 cm (50). Mean postoperative followup was 47 months. RESULTS Overall and cancer specific 5-year survival for the entire series was 81 and 92%, respectively. Of 44 patients with recurrent renal cell carcinoma 16 (3.2%) had local recurrence and 28 (5.8%) had metastatic disease. There was no difference in 5-year cancer specific survival or tumor recurrence between groups 1 and 2 or groups 3 and 4. However, these outcome measures were significantly more favorable in groups 1 and 2 combined (tumors 4 cm. or less) compared to groups 3 and 4 combined (tumors more than 4 cm.) (p = 0.001). CONCLUSIONS Following nephron sparing surgery for localized sporadic renal cell carcinoma cancer-free survival is significantly better in patients with tumors 4 cm. or less compared to those with larger tumors. The usefulness of the current TNM staging system can be improved by subdividing T1 tumors into T1a (4 cm. or less) and T1b (4 to 7 cm.).

Laparoscopic partial nephrectomy for renal tumor: duplicating open surgical techniques.

PURPOSE We describe our technique of and single institutional experience with purely laparoscopic partial nephrectomy for renal tumor, wherein the focus is to duplicate established open techniques of oncologic nephron sparing surgery. MATERIALS AND METHODS Since August 1999 laparoscopic partial nephrectomy for renal tumor has been performed in 50 patients. Of the patients 24 (48%) had either a compromised contralateral kidney (20) or a solitary kidney (4). Mean tumor size was 3.0 cm. (range 1.4 to 7). In 9 patients (18%) the inner margin of the tumor was in close proximity to the pelvicaliceal system. Our current laparoscopic technique involves preoperative ureteral catheterization, laparoscopic renal ultrasonography, transient atraumatic clamping of the renal artery and vein, tumor excision with an approximate 0.5 cm. margin using cold endoshears and/or J-hook electrocautery, pelvicaliceal suture repair (if necessary) and suture repair of the renal parenchymal defect over surgicel bolsters. In 1 case renal surface hypothermia was achieved laparoscopically with ice slush. All suturing and knot tying were performed with free hand intracorporeal laparoscopic techniques exclusively. RESULTS All procedures were successfully completed without open conversion. Mean surgical time was 3.0 hours (range, 0.75 to 5.8) and mean blood loss was 270.4 cc (range 40 to 1,500). Mean warm ischemia time was 23 minutes (range, 9.8 to 40). Caliceal entry in 18 cases (36%) was suture repaired in a watertight manner. Following caliceal repair, none of these 18 patients had a postoperative urine leak. Hospital stay averaged 2.2 days (range 1 to 9). Major complications occurred in 3 patients (6%) including intraoperative hemorrhage in 1, delayed hemorrhage necessitating nephrectomy in 1 and urine leak in 1. Renal cell carcinoma was confirmed on pathological examination in 34 patients (68%), and all had negative inked surgical margins for cancer. During a mean followup of 7.2 months (range 1 to 17) no patient has had local or port site recurrence or metastatic disease. CONCLUSIONS Laparoscopic partial nephrectomy is a viable alternative for select patients with a renal tumor. The largest single institutional experience to date is presented wherein the open techniques of nephron sparing surgery have been duplicated laparoscopically.

Nephron-Sparing Surgery for Renal Cell Carcinoma

Nephron-sparing surgery has become an established surgical treatment for patients with renal cell carcinoma (RCC), particularly in situations in which preservation of renal parenchyma is critical. However, due to the fear of local renal fossa recurrence with nephron-sparing surgery, radical nephrectomy has historically been the treatment of choice for patients with unilateral RCC and a normal contralateral kidney. Recently, increased incidence of low-stage, localized, solitary RCC has led to renewed interest in partial nephrectomy. With excellent disease-specific survival and recurrence rates comparable to that achieved with radical nephrectomy, nephron-sparing surgery can be confidently utilized in treating patients with stage T1 RCC lesions (<7 cm) and a normal contralateral kidney. The utility of nephron-sparing surgery in the context of adjunctive systemic immunotherapy remains to be explored.

Management of small unilateral renal cell carcinomas: Radical versus nephron-sparing surgery

OBJECTIVES There is controversy concerning the management of small unilateral renal cell carcinomas. The present study was undertaken to evaluate the relative efficacy of radical nephrectomy versus nephron-sparing surgery in such patients. METHODS Patients with a single, small (less than 4 cm), localized, unilateral, sporadic renal cell carcinoma (RCC) were identified from an institutional registry. From 1975 to 1992, 88 patients fulfilling these criteria were treated with either radical nephrectomy (n = 42) or nephron-sparing surgery (n = 46). The mean postoperative follow-up interval is 48 +/- 29 months. RESULTS The radical and nephron-sparing surgical groups were well matched for patient age, sex, renal function, diabetes, hypertension, tumor size, tumor location, and tumor stage. All patients in both groups had low pathologic stage RCC. There was no difference between the two groups in terms of the mean hospital stay, the requirement for blood transfusions, or the occurrence of surgical complications. There was no difference in the mean preoperative and postoperative serum creatinine levels for patients in the nephron-sparing surgery group. However, the mean postoperative serum creatinine levels were significantly higher than the mean preoperative levels for patients in the radical nephrectomy group (P < 0.001). A single patient in each group developed recurrent RCC postoperatively. The cancer-specific 5-year survival rate for patients in the radical and nephron-sparing surgical groups is 97% and 100%, respectively. CONCLUSIONS Radical nephrectomy and nephron-sparing surgery each provide safe and effective curative treatment for patients with a single, small, unilateral localized RCC. The long-term renal functional advantage of nephron-sparing surgery in this setting is not established.

Nephrectomy Induced Chronic Renal Insufficiency is Associated With Increased Risk of Cardiovascular Death and Death From Any Cause in Patients With Localized cT1b Renal Masses

PURPOSE Radical nephrectomy has traditionally been preferred to partial nephrectomy in patients with localized renal cell cancer because of its simplicity and established cancer control. Recent data suggest that these patients have significant competing risks of death, some of which may be increased by chronic renal insufficiency. Therefore, we compared overall survival, cancer specific survival and cardiac specific survival in patients undergoing partial or radical nephrectomy for cT1b tumors. MATERIALS AND METHODS From 1999 to 2006, 1,004 patients with renal masses between 4 and 7 cm underwent extirpative surgery, partial nephrectomy (524) or radical nephrectomy (480). We generated a propensity model based on preoperative patient characteristics, and then modeled survival with the additional variables of pathological stage and new baseline renal function. RESULTS On multivariate analysis cancer specific survival was equivalent for patients treated with partial nephrectomy or radical nephrectomy. Those patients undergoing radical nephrectomy lost significantly more renal function than those undergoing partial nephrectomy. The average excess loss of renal function observed with radical nephrectomy was associated with a 25% (95% CI 3-73) increased risk of cardiac death and 17% (95% CI 12-27) increased risk of death from any cause on multivariate analysis. CONCLUSIONS Partial nephrectomy offers cancer specific survival equivalent to that of radical nephrectomy and is technically feasible in at least 50% of patients with cT1b tumors. Preservation of renal function was significantly better in patients treated with partial nephrectomy. Postoperative renal insufficiency was a significant independent predictor of overall and cardiovascular specific survival, and efforts should be made to limit the renal function loss associated with surgery for localized renal masses.

Laparoscopic renal cryoablation in 32 patients

OBJECTIVES Laparoscopic renal cryoablation is a developmental minimally invasive nephron-sparing treatment alternative for highly select patients with small renal tumors. We present our evolving experience with this procedure. METHODS Thirty-two patients (34 tumors) with a mean tumor size of 2.3 cm on preoperative computed tomography underwent laparoscopic renal cryoablation. As dictated by the tumor location, cryoablation was performed by either the retroperitoneal (n = 22) or the transperitoneal (n = 10) laparoscopic approach using real-time ultrasound monitoring. A double freeze-thaw cycle was routinely performed. RESULTS The mean surgical time was 2.9 hours, cryoablation time 15.1 minutes, and blood loss 66.8 mL. For a mean intraoperative ultrasonographic tumor size of 2 cm, the mean cryolesion size was 3.2 cm. The hospital stay was less than 23 hours in 22 (69%) of 32 patients. Sequential magnetic resonance imaging scans demonstrated a gradual contraction in the mean diameter of the cryolesions. Of the 20 patients who underwent a 1-year follow-up magnetic resonance imaging scan, the cryoablated tumor was no longer visible in 5. Of note, 23 patients have now undergone a 3 to 6-month follow-up computed tomography-directed biopsy of the cryoablated tumor site; the biopsy was negative for cancer in all 23 patients. No evidence of local or port-site recurrence was found during a mean follow-up of 16.2 months. CONCLUSIONS Critical long-term data regarding laparoscopic renal cryoablation, a developmental technique, are awaited. However, our initial experience is cautiously optimistic. Despite its significant potential for false-negative results, it is encouraging that the follow-up computed tomography-directed needle biopsies at 3 to 6 months were negative for cancer in 23 of 23 patients.

Factors Predicting Renal Functional Outcome After Partial Nephrectomy

PURPOSE Compared to radical nephrectomy, partial nephrectomy better preserves renal parenchyma and function. Although several clinical factors may impact renal function after partial nephrectomy including preoperative function, age, gender and comorbidities, the contributions of tumor and surgical factors have not been well studied. We evaluate independent factors predicting functional outcomes after partial nephrectomy. MATERIALS AND METHODS Preoperative and all postoperative serum creatinine values for 1,169 patients undergoing partial nephrectomy were used to estimate glomerular filtration rate. Postoperative nadir glomerular filtration rate and ultimate glomerular filtration rate were analyzed using multiple pertinent covariates. RESULTS Median preoperative, postoperative nadir and ultimate glomerular filtration rates were 77, 57 and 71 ml per minute per 1.73 m(2), respectively. Increasing age, gender, lower preoperative glomerular filtration rate, solitary kidney, tumor size, ischemia time and longer time to nadir glomerular filtration rate significantly predicted postoperative nadir glomerular filtration rate and ultimate glomerular filtration rate. Acute loss of renal function predicted lower ultimate glomerular filtration rate. In the entire cohort, in patients with normal preoperative renal function, and in those with baseline stage 3 and those with stage 4 chronic kidney disease the incidence of postoperative acute kidney injury after partial nephrectomy was 3.6%, 0.8%, 6.2% and 34%, and the incidence of chronic end stage renal disease after partial nephrectomy was 2.5%, 0.1%, 3.7% and 36%, respectively. CONCLUSIONS Lower preoperative glomerular filtration rate, solitary kidney, older age, gender, tumor size and longer ischemic interval all predicted lower glomerular filtration rate after partial nephrectomy. Therefore, duration of renal ischemia is the strongest modifiable surgical risk factor for decreased renal function after partial nephrectomy, and efforts to limit ischemic time and injury should be pursued in open and laparoscopic partial nephrectomy.

Long-Term Follow-up after Partial Removal of a Solitary Kidney

BACKGROUND The removal of more than one kidney in animals leads to proteinuria and progressive renal failure due to focal segmental glomerulosclerosis. This injury may be the result of chronic glomerular hyperfiltration. The purpose of this study was to determine the effect of a reduction in renal mass of more than 50 percent on residual renal function and morphology in humans. METHODS We evaluated long-term renal function in 14 patients with a solitary kidney who had undergone partial nephrectomy for renal-cell or transitional-cell carcinoma. In 12, the first kidney had been removed 2 months to 21 years previously for the same type of cancer; in 2, the other kidney was congenitally atrophic. Before surgery, no patient had clinical or histopathological evidence of primary renal disease. All 14 patients underwent partial nephrectomy to remove a localized tumor, with 25 to 75 percent of the solitary kidney being excised. They were evaluated 5 to 17 years after surgery (mean, 7.7). RESULTS Twelve patients had stable postoperative renal function, and end-stage renal failure developed in two. There were no changes in blood pressure in any patient during follow-up. Nine patients had proteinuria, which was mild (0.15 to 0.8 g of urinary protein per day) in five. The extent of proteinuria was inversely correlated with the amount of remaining renal tissue (P = 0.0065) and directly correlated with the duration of follow-up (P = 0.0005). Four patients with moderate-to-severe proteinuria had renal biopsies, which revealed focal segmental glomerulosclerosis in three patients and global glomerulosclerosis in one. CONCLUSIONS Long-term renal function remains stable in most patients with a reduction in renal mass of more than 50 percent. These patients are, however, at increased risk for proteinuria, glomerulopathy, and progressive renal failure.