Contemporary use of partial nephrectomy at a tertiary care center in the United States

Renal functional outcomes after partial nephrectomy with extended ischemic intervals are better than after radical nephrectomy

PURPOSE

Partial nephrectomy is now a standard of care for clinical stage T1 renal cancers amenable to a nephron sparing approach. Based on tumor size and location, some partial nephrectomies can be more challenging and necessitate longer ischemic intervals, and radical nephrectomy is considered an alternative standard of care for these tumors. We evaluate whether partial nephrectomy with extended ischemia provides improved renal functional outcomes compared with radical nephrectomy.

MATERIALS AND METHODS

Renal functional outcomes were analyzed in 2,402 consecutive patients with serum creatinine 1.4 mg/dl or less and 2 functioning kidneys treated for cT1 renal cancer at Cleveland Clinic with partial (1,833, 76%) or radical nephrectomy (569, 24%). Patients treated with partial nephrectomy were grouped according to duration of ischemia using the categories of limited (less than 30 minutes), unknown or extended (greater than 30 minutes).

RESULTS

Patients in all 4 groups had similar preoperative creatinine (median 0.9 mg/dl) and estimated glomerular filtration rate (median 82 to 84 ml/minute/1.73 m(2)). Patients undergoing radical nephrectomy on average were older, and had more comorbidities and larger tumors (p <0.001). Regardless of type of surgery, this cohort as a whole was at low risk (less than 1%) for renal failure (estimated glomerular filtration rate less than 15 ml/minute/1.73 m(2)). However, patients in the radical nephrectomy cohort were far more likely (p <0.001) to have an estimated glomerular filtration rate less than 45 ml/minute/1.73 m(2) (35%) than any of the partial nephrectomy groups (limited 11%, unknown 15%, extended ischemia 19%).

CONCLUSIONS

Even when performed with extended ischemia, partial nephrectomy is associated with renal functional outcomes superior to those of radical nephrectomy for clinical stage T1 renal cancers. Partial nephrectomy should be considered even for tumors in which anticipated ischemia may exceed 30 minutes.

Trends in renal tumor surgery delivery within the United States

BACKGROUND

Most small renal tumors are amenable to partial nephrectomy (PN). Studies have documented the association of radical nephrectomy (RN) with an increased risk of comorbid conditions, such as chronic kidney disease. Despite evidence of equivalent oncologic outcomes, PN remains under used within the United States. In this study, the authors identified the most recent trends in kidney surgery for small renal tumors and determined which factors were associated with the use of PN versus RN within the United States.

METHODS

A population-based patient cohort was analyzed using the Surveillance, Epidemiology and End Results cancer registry (SEER 1999-2006). The authors identified 18,330 patients ages 40 to 90 years who underwent surgery for kidney tumors <or=4 cm in the United States between 1999 and 2006.

RESULTS

In total, 11,870 patients (65%) underwent RN, and 6460 patients (35%) underwent PN. The ratio of PN to RN increased yearly (P < .001), representing 45% of kidney surgeries in 2006 for small tumors. There were significant differences in the cohort of patients who underwent PN versus RN, including age, sex, tumor location, marital status, year of treatment, and tumor size. When adjusting for these variables, being a man, age <or=70 years, urban residence, smaller tumor size, and more recent treatment year were predictors of PN.

CONCLUSIONS

Although the total numbers of PN procedures increased in the United States between 1999 and 2006, there remains a significant under use of PN, particularly among women, the elderly, and those living in rural locations. Further investigation will be required to determine the reasons for these disparities, and strategies to optimize access to PN need to be developed.

[What is the importance of kidney cancer surgery in contrast with targeted therapies?]

Despite the extraordinary development of the medical treatment of kidney cancer, its treatment remains very surgical in localized and metastatic stage. Advances in surgery have accompanied the advent of targeted therapies. The laparoscopy has become the reference procedure for radical nephrectomy in the case of T1-T2 tumors. Partial nephrectomy, currently widespread, should be the first surgical procedure to consider in cases of tumors less than 4 cm. Partial nephrectomy for tumors between 4 and 7 cm is feasible for selected patients with favorable tumor localization. In the future, the use of neo-adjuvant anti-angiogenesis agents could broaden the scope of partial nephrectomy. Laparoscopic partial nephrectomy is spreading but is still considered as a therapeutic option, conducted in reference centres. In case of metastatic disease, pending the results of randomized trials including patients on anti-angiogenesis agents, cytoreductive nephrectomy remains indicated for patients in good general condition with kidney cancer metastatic immediately.

[Laparoscopic radical and partial nephrectomy: an overview]

Laparoscopy has been progressively gaining acceptance in the urologic arena. The start with renal surgery was slow; however, after complete establishment for benign indications the breakthrough occurred due to the success of laparoscopy in the field of oncologic surgery. Laparoscopic radical nephrectomy for stage T1 and T2 tumours, whether transperitoneal or retroperitoneal, can be performed safely. The surgical steps duplicate the open procedure. The overall complication rate is low and does not significantly differ from that of the open procedure. Laparoscopic partial nephrectomy is, in contrast, a technically challenging procedure despite its realisation laparoscopically. Although the intermediate outcomes are comparable to those of the open procedure, there are concerns related to warm ischemia time and the risk of major complications such as urinary leakage and haemorrhage requiring transfusion, so that it should be performed only in centres with expertise.

Complications after radical and partial nephrectomy as a function of age

PURPOSE

Partial nephrectomy may be underused compared with radical nephrectomy in elderly patients due to concerns about higher complication rates. We determined if the association of age and perioperative outcomes differed between nephrectomy types.

MATERIALS AND METHODS

We identified patients who underwent radical or partial nephrectomy between January 2000 and October 2008. Using multivariable methods we determined whether the relationship between age and risk of postoperative complications, estimated blood loss or operative time differed by nephrectomy type.

RESULTS

Of 1,712 patients 651 (38%) underwent radical nephrectomy and 1,061 (62%) underwent partial nephrectomy. Patients treated with partial nephrectomy had higher complication rates than those who underwent radical nephrectomy (20% vs 14%). In a multivariable model age was significantly associated with a small increase in risk of complications (OR for 10-year age increase 1.17, 95% CI 1.04-1.32, p = 0.009). When including an interaction term between age and procedure type, the interaction term was not significant (p = 0.09), indicating there was no evidence the risk of complications associated with partial vs radical nephrectomy increased with advancing age. There was no evidence that age was significantly associated with estimated blood loss or operative time.

CONCLUSIONS

We found no evidence that elderly patients experience a proportionally higher complication rate, longer operative times or higher estimated blood loss from partial nephrectomy than do younger patients. Given the advantages of renal function preservation we should expand the use of nephron sparing treatment to renal tumors in elderly patients.

Urinary fistulae after partial nephrectomy

OBJECTIVE

To report the risk factors and natural history of urinary fistula (UF) after partial nephrectomy (PN), as their incidence has been reported to be 3-6% in large series of PN but there are few reports of the risk factors associated with the development of UF after PN, and the natural history of UF in a large group of patients.

PATIENTS AND METHODS

This was a retrospective review of 1118 PN at one tertiary-care institution. Most patients had a drain placed in the perinephric space after surgery. Fifty-two patients were identified as having a UF if they had persistent flank drainage for >14 days after surgery, or presented with evidence of a UF after the drain had been removed. Risk factors for development and the course of the UF are reported.

RESULTS

Fifty-two patients developed a UF after PN (4.4%, 95% confidence interval, CI, 3.5-6.1%) The rate of a persistent urine leak (defined as drain fluid consistent with urine for >2 weeks after surgery) was 4.0 (95% CI 2.9-5.3)%. The overall rate of delayed UF presentation was only 0.4 (0.09-0.9)%. Patients who developed a UF had larger tumours (3.5 vs 2.6  cm, P= 0.03), a higher estimated blood loss (400 vs 300  mL, P < 0.001), and longer ischaemia time (50 vs 39  min, P < 0.001) than patients who did not develop a UF. Differences in tumour histology, laterality, multifocality, type of surgery (laparoscopic vs open), and intraoperative collecting system entry were not statistically different in patients who did or did not develop a UF. Patients with tumours of >2.5  cm were twice as likely to develop a UF than patients with tumours of <2.5  cm (P= 0.02). Most patients were managed conservatively with a percutaneous drain until the UF resolved, if they were asymptomatic. Overall, in 36 patients (69%) the fistula resolved with no intervention, while 16 (31%) required intervention. Stenting was the commonest intervention (15%). No patient required re-operative open surgery.

CONCLUSION

The rate of development of UF after PN is low. Tumour size, blood loss and ischaemia time were all associated with the development of a UF. In most patients with a urine leak immediately after surgery the UF will resolve with no intervention, and can be managed conservatively with patience, in the absence of clinical symptoms.

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.