Long-term management of bilateral, multifocal, recurrent renal carcinoma

Impact of tumor multiplicity on the prognosis of patients with primary renal cell carcinoma: a SEER database analysis

To compare clinical characteristics and survival outcomes of patients with multiple renal cell carcinoma versus single renal cell carcinoma. Develop a prognostic model for predicting prognosis in patients with multiple tumors and analyze prognostic factors. Patients with primary multiple renal cell carcinoma were selected from the Surveillance, Epidemiology, and End Results database (2004-2015). They were divided into single-tumor and multiple-tumor groups. Survival analysis was conducted using the Kaplan-Meier method and log-rank test. A Cox regression model was used to identify potential prognostic factors. A total of 19,489 renal cell carcinoma cases were included, with 947 in the multiple-tumor group and 18,542 in the single-tumor group. The multiple-tumor group had lower cancer-specific survival (P = 0.03, HR = 1.431). Cox regression identified risk factors for the multiple-tumor group including number of tumors, gender, combined summary stage, T stage, N stage, tumor size, and type of surgery. The predicted probabilities showed acceptable agreement with the actual observations at 3-, 5-, and 8-years area under the curve values in both the training and validation cohorts (0.831 vs. 0.605; 0.775 vs. 0.672; and 0.797 vs. 0.699, respectively). Compared with single renal cell carcinoma, multiple renal cell carcinoma is associated with decreased cancer-specific survival. Additionally, we identified several prognostic factors including the number of tumors, T stage, tumor size, and type of surgery. These findings offer valuable insights for selecting appropriate treatment strategies for patients diagnosed with multiple renal cell carcinomas.

Effectiveness of Thermal Ablation for Renal Cell Carcinoma after Prior Partial Nephrectomy

Background

Repeat partial nephrectomy (PN) for tumors recurring in the ipsilateral kidney is associated with surgical complexity and a higher rate of complications.

Objective

To evaluate the local oncologic efficacy of thermal ablation (TA) for renal cell carcinoma (RCC) in the ipsilateral kidney following PN.

Design setting participation

We included patients who underwent ablation for renal tumors in the ipsilateral kidney after PN between January 2005 and December 2019. Demographics, tumor size, procedural details, complications, pathology, local oncologic outcomes, and survival outcomes are described.

Outcome measurements and statistical analysis

The procedural, pathologic, and oncologic outcomes are described. Survival rates were estimated using the Kaplan-Meier method.

Results and limitations

A total of 66 patients (46 male and 20 female) with a median age of 62 yr (interquartile range [IQR] 52-69) met our inclusion criteria. In these patients, 74 TA procedures were performed for 86 lesions (median tumor size 1.9 cm, IQR 1.6-2.5). Radiofrequency ablation and cryoablation accounted for 60 (81%) and 14 (19%) procedures, respectively. Three patients (3.7%) had Clavien-Dindo grade III complications. Of 65 lesion biopsies, 62 (95.5%) were diagnostic. The most common subtype was clear cell RCC (n = 37). The median imaging follow-up duration was 60 mo (IQR 43-88). Recurrence in the ablation zone occurred for four lesions (4.6%) at a median of 6.9 mo (IQR 6.4-10.7). The rates of overall, recurrence-free, and disease-free survival were 93.1%, 94.4%, and 65.6% at 5 yr, and 71.6%, 94.4%, and 60.1% at 10 yr, respectively. Limitations include the retrospective design and the lack of a control group.

Conclusions

TA is effective for the treatment of RCC in the ipsilateral kidney following PN.

Patient summary

Heat treatment to remove tumor tissue is an effective option for small kidney masses recurring after partial kidney removal for cancer. Long-term follow-up data revealed that this treatment resulted in low recurrence and complication rates.

Comparative analysis of salvage partial nephrectomy versus radical nephrectomy after the failure of initial partial nephrectomy

OBJECTIVES

To compare the oncologic outcomes and renal function discrepancy of salvage partial nephrectomy (sPN) and salvage radical nephrectomy (sRN) after an initial failed PN.

MATERIALS AND METHODS

Retrospective data from multiple centers between 2008 and 2022 were analyzed in this study. Patients who received sPN or sRN after an initial failed PN were identified. Comparative analysis and propensity score matching (PSM) was performed and the RENAL score, tumor size, and pathological T stage at salvage surgery were used to match the 2 groups. Local recurrence-free survival (LRFS) and recurrence-free survival (RFS) were assessed using the Cox proportional hazards model and log-rank tests. Renal function after salvage surgery was assessed using the Wilcoxon rank sum test.

RESULTS

A total of 140 patients who underwent salvage surgery were evaluated, of whom 60 were considered for PSM analysis after matching. At a median follow-up of 27.0 months, LRFS and RFS showed no significant difference between sPN and sRN, either before (LRFS, HR = 0.673 [95% CI: 0.171-2.644], P = 0.610; RFS, HR = 0.744 [95% CI: 0.271-1.344], P = 0.595) or after matching (LRFS, HR = 1.080 [95% CI: 0.067-17.30], P = 0.957; RFS, HR = 1.199 [95% CI: 0.241-5.983], P = 0.822). During long-term follow-up, sPN preserved renal function (after matching, eGFR, 71.4 vs. 54.0, P < 0.001) and prevented eGFR loss (after matching: 6.6% vs. 25.6%, P < 0.001).

CONCLUSION

Salvage partial nephrectomy offers a better alternative than sRN for recurrence after initial PN, as sPN preserves renal function better while maintaining parallel tumor control and acceptable complication rates.

Real-time calcium uptake monitoring of a single renal cancer cell based on an all-solid-state potentiometric microsensor

Introduction: In addition to many cellular processes, Ca2+ is also involved in tumor initiation, progression, angiogenesis, and metastasis. The development of new tools for single-cell Ca2+ measurement could open a new avenue for cancer therapy.

Methods: The all-solid-state calcium ion-selective microelectrode (Ca2+-ISμE) based on carbon fiber modified with PEDOT (PSS) as solid-contact was developed in this work, and the characteristics of the Ca2+-ISμE have also been investigated.

Results: The Ca2+-ISμE exhibits a stable Nernstian response in CaCl2 solutions in the active range of 1.0 × 10−8 - 3.1 × 10−3 M with a low detection limit of 8.9 × 10−9 M. The Ca2+-ISμE can be connected to a patch clamp to fabricate a single-cell analysis platform for in vivo calcium monitoring of a single renal carcinoma cell. The calcium signal decreased significantly (8.6 ± 3.2 mV, n = 3) with severe fluctuations of 5.9 ± 1.8 mV when the concentration of K+ in the tumor microenvironment is up to 20 mM.

Discussion: The results indicate a severe cell response of a single renal carcinoma cell under high K+ stimuli. The detection system could also be used for single-cell analysis of other ions by changing different ion-selective membranes with high temporal resolution.

Operative and oncological outcomes of salvage robotic radical and partial nephrectomy: a multicenter experience

We aim to describe the perioperative and oncological outcomes for salvage robotic partial nephrectomy (sRPN) and salvage robotic radical nephrectomy (sRRN). Using a prospectively maintained multi-institutional database, we compared baseline clinical characteristics and perioperative and postoperative outcomes, including pathological stage, tumor histology, operative time, ischemia time, estimated blood loss (EBL), length of stay (LOS), postoperative complication rate, recurrence rate, and mortality. We identified a total of 58 patients who had undergone robotic salvage surgery for a recurrent renal mass, of which 22 (38%) had sRRN and 36 (62%) had sRPN. Ischemia time for sRPN was 14 min. The median EBL was 100 mL in both groups (p = 0.581). One intraoperative complication occurred during sRRN, while three occurred during sRPN cases (p = 1.000). The median LOS was 2 days for sRRN and 1 day for sRPN (p = 0.039). Postoperatively, one major complication occurred after sRRN and two after sRPN (p = 1.000). The recurrence reported after sRRN was 5% and 3% after sRPN. Among the patients who underwent sRRN, the two most prevalent stages were pT1a (27%) and pT3a (27%). Similarly, the two most prevalent stages in sRPN patients were pT1a (69%) and pT3a (6%). sRRN and sRPN have similar operative and perioperative outcomes. sRPN is a safe and feasible procedure when performed by experienced surgeons. Future studies on large cohorts are essential to better characterize the importance and benefit of salvage partial nephrectomies.

Active surveillance of small renal masses

Most renal masses incidentally detected by cross-sectional images are benign, being mainly cysts, and if they are malignant, they are indolent in nature with limited metastatic potential. Enhanced renal masses less than 4 cm in size are known as small renal masses (SRMs), and their growth rate (GR) and the possibility of developing metastasis are extremely low. Delayed intervention of SRMs by closed and routine imaging follow-up known as active surveillance (AS) is now an option according to urological guidelines. Radiologists have a key position in AS management of SRMs even unifocal and multifocal (sporadic or associated with genetic syndromes) and also in the follow-up of complex renal cysts by Bosniak cyst classification system. Radiologists play a key role in the AS of both unifocal and multifocal (sporadic or associated with genetic syndromes) SRMs as well as in the follow-up of complex renal cysts using the Bosniak cyst classification system. Indeed, radiologists must determine which patients with SRMs or complex renal cysts can be included in AS, establish the follow-up radiological test algorithm to be used in different scenarios, perform measurements in follow-up tests, and decide when AS should be discontinued. The purpose of this article is to review the indications and management of AS in SRMs, especially focused on specific scenarios, such as complex renal cysts and multifocal renal tumors (sporadic or hereditary). In this work, the authors aimed to provide a thorough review of imaging in the context of active surveillance of renal masses.

Image-guided laser ablation in the treatment of recurrence of renal tumours: technique and preliminary results

Abdominal recurrences of renal cell carcinoma (RCC) after surgery might represent a challenge for treatment, often requiring difficult surgeries or anticipated systemic therapy. Our aim is to illustrate a novel application of laser ablation for the treatment of abdominal recurrences of RCC. Patients with abdominal recurrences of renal cancer were treated under ultrasound/computed tomography guidance with a diode laser inserted into the lesion through a thin 21-G needle. A fixed 3-W power protocol was used, changing the illumination time according to lesion dimension and shape. Also, technical success, technical efficacy, local tumour progression, and major and minor complications were retrospectively analysed. Three patients were treated with image-guided laser ablation for abdominal recurrences of RCC. In all cases, it was possible to perform ablation as preoperatively planned and all three nodules (size of 6, 8, and 12 mm) were completely ablated with no evidence of residual enhancement after 6 weeks at contrast-enhanced CT. No minor or major complications were observed. No local tumour progression was reported up to 12 months from ablation. Image-guided laser ablation holds the potential to offer a minimally invasive treatment to patients with abdominal recurrence of RCC. Further studies are needed to evaluate the clinical role of this technique.

A comparison of outcomes for standard and multiplex partial nephrectomy in a solitary kidney: The National Cancer Institute experience

OBJECTIVES

To study the short and intermediate surgical, renal functional, and oncologic outcomes of multiplex partial nephrectomy (mPN) and standard partial nephrectomy (sPN) in the setting of a solitary kidney.

PATIENTS AND METHODS

Review of a prospectively maintained database of patients undergoing solitary kidney partial nephrectomy at our institution was performed. Patients were stratified into 2 cohorts: mPN-where 3 or more renal tumors were resected and sPN-where 1 or 2 tumors were resected. Perioperative, renal functional, and oncological outcomes were compared.

RESULTS

Ninety-three patients with a solitary kidney underwent a total of 121 surgical procedures; 43 (35.5%) were sPN and 78 (64.4%) were mPN. The total and major (Clavien Grade III and IV) complication rates between sPN and mPN were similar (57.1% vs. 70.1%, P = 0.2; 31.0% vs. 35.1%, P = 0.3). At 12 months post-op, the percentage of patients with eGFR > 45 was similar in each group (sPN 87.0%, mPN 73.7%; P = 0.2), and long-term hemodialysis rates were 4.7% and 6.4%, respectively. Completion nephrectomy was performed in 2.3% of sPN and 2.6% of mPN. At a median follow-up of 40.1 months, the metastasis rate was 8.6% in the sPN group and 4.1% in the mPN group (P = 0.4).

CONCLUSIONS

Partial nephrectomy in the setting of a solitary kidney can effectively preserve renal function. The renal functional and oncologic outcomes were similar in sPN and mPN, with low hemodialysis rates and complication rates within the expected range of these operations. Three or more tumors in a solitary kidney should not be a contraindication for nephron sparing surgery.

[One-stage cryoablation of two renal tumors]

The progressive development of medical technologies allowed the introduction of alternative methods of treatment of localized renal cell carcinoma with a tendency to organ-sparing approach. Cryoablation, radiofrequency ablation, and some experimental methods of treatment (microwave and laser ablation, therapy with high-intensity focused ultrasound) are referred to minimally invasive treatment of renal cell carcinoma. Cryoablation is highly effective alternative method of treatment of renal cell carcinoma. The main advantages of this technique are tumor visualization and formation of 'ice ball' in real time, fewer complications compared with other methods, as well as the possibility of cryotherapy in critically ill patients. Compared to other ablative technologies, cryoablation is followed by low percentage of redo treatment and good intermediate oncological results. We described the experience of one-stage cryoablation of two kidney tumors in this report.

Collaborative Review of Risk Benefit Trade-offs Between Partial and Radical Nephrectomy in the Management of Anatomically Complex Renal Masses

BACKGROUND

While partial nephrectomy (PN) is the recommended treatment for many small renal masses, anatomically complex tumors necessitate a clear understanding of the potential risks and benefits of PN and radical nephrectomy (RN).

OBJECTIVE

To critically review the comparative effectiveness evidence of PN versus RN; to describe key trade-offs involved in this treatment decision; and to highlight gaps in the current literature.

EVIDENCE ACQUISITION

A collaborative critical review of the medical literature was conducted.

EVIDENCE SYNTHESIS

Patients who undergo PN for an anatomically complex or large mass may be exposed to perioperative and potential oncologic risks that could be avoided if RN were performed, while patients who undergo RN may forgo long-term benefits of renal preservation. Decision-making regarding the optimal treatment with PN or RN among patients with anatomically complex or large renal mass is highly nuanced and must balance the risks and benefits of each approach. Currently, high-quality evidence on comparative effectiveness is sparse. Retrospective comparisons are plagued by selection biases, while the one existing prospective randomized trial, albeit imperfect, suggests that nephron-sparing surgery may not benefit all patients.

CONCLUSIONS

For anatomically complex tumors, PN preserves renal parenchyma but may expose patients to higher perioperative risks than RN. The risks and benefits of each surgical approach must be better objectified for identification of patients most suitable for complex PN. A prospective randomized trial is warranted and would help in directing patient counseling.

PATIENT SUMMARY

Treatment decisions for complex renal masses require shared decision-making regarding the risk trade-offs between partial and radical nephrectomy.

Bilateral renal cancers: oncological and functional outcomes

PURPOSE

The authors assessed the characteristics of bilateral renal cancers.

METHODS

From January 1995 to January 2015, 65 patients underwent surgery for bilateral renal cancers. Thirty-four of the patients had 36 synchronous tumors, while the remaining 29 had metachronous tumors. The mean age of the patients was 60 ± 11 years. There were 22 females and 43 males. In all cases, bilateral partial nephrectomies or unilateral nephrectomy and contralateral nephron-sparing surgery were performed.

RESULTS

The mean sizes of the synchronous tumors were 5.0 ± 2.7 and 4.7 ± 3.0 cm at the first and the second operations, respectively. The average diameters of the metachronous carcinomas were 6.6 ± 3.0 and 3.1 ± 1.6 cm at the initial and the second surgeries, respectively. Histologic concordance was 91.1 % in the synchronous and 96.5 % in the metachronous tumors. The mean postoperative creatinine levels increased by 116 %, while the GFR decreased by 44.8 % in synchronous tumors at the second operation. The mean postoperative creatinine levels increased by 42 %, while the GFR decreased by 30.4 % in metachronous carcinomas at the second operation. The mean follow-up time was 4.8 ± 3.7 years. During this period, distant metastases occurred in two patients with synchronous tumors and in six cases with metachronous tumors. Local recurrences were detected in one case of synchronous tumor and in four patients with metachronous carcinomas. The 5-year overall and tumor-specific survivals were 53 and 80 %, respectively.

CONCLUSIONS

In patients with bilateral renal carcinomas, the histologic concordance was 93.6 %. The bilateral partial nephrectomies or unilateral nephrectomy and contralateral resection provided acceptable oncological and functional outcomes.

Clear cell papillary renal cell carcinoma as part of histologically discordant multifocal renal cell carcinoma: A case report and review of literature

BACKGROUND

Multifocal renal cell carcinoma of different histological subtypes within a single kidney is rare. We report a recently classified clear cell (tubulo) papillary renal cell carcinoma as part of an unusual case of multifocal renal cell carcinoma of discordant histological subtypes.

RESULTS

A 57 year-old-man was found to have multiple renal tumors and cysts on imaging and underwent a laparoscopic left radical nephrectomy. Pathological review showed multifocal renal cell carcinoma (clear cell (tubulo) papillary, clear cell and papillary renal cell carcinomas and papillary adenomas). Morphology of clear cell papillary renal cell carcinoma was supported by immunohistochemical profile (CK7+, HMWK+, CAIX+, AMACR-, CD10-, TFE3-).

CONCLUSIONS

This is the first report of clear cell papillary renal cell carcinoma as part of multifocal renal cell carcinoma of different histological subtypes. Related lineage of clear cell renal cell carcinoma and papillary renal cell carcinoma is supported by the highest prevalence of their combination within multifocal renal cell carcinoma of different histological subtypes along with their molecular interconnection. Clear cell papillary renal cell carcinoma may be uniquely placed between clear cell and papillary renal cell carcinomas since it shows morphological features intermediate between clear cell and papillary renal cell carcinoma along with overlapping but unique immunohistochemical profile. Clear cell papillary renal cell carcinoma may be molecularly related to clear cell and papillary renal cell carcinomas since the tumors overexpress markers of HIF pathway activation with normal/elevated VHL mRNA expression and some tumors show losses of chromosome 3. Due to the overlapping morphology, it is possible that cases of clear cell papillary renal cell carcinoma may have been misclassified as papillary or clear cell renal cell carcinoma in the literature, incorrectly increasing their reported prevalence. Identification of multifocal RCCs may be related to the extent of pathological sampling.

Nephron-sparing surgery for multifocal and hereditary renal tumors

PURPOSE OF REVIEW

Despite the controversy surrounding the benefits of nephron-sparing surgery, multiple absolute indications for nephron-sparing surgery still exist, including the classic indications of hereditary and bilateral kidney tumors.

RECENT FINDINGS

Multiple genetic mutations have been identified which lead to hereditary kidney cancer conditions. These are briefly reviewed because the surgical management of hereditary kidney tumors depends on the genetic and histologic subtypes involved. Clear understanding of these hereditary conditions is crucial for proper surgical management of these tumors.

SUMMARY

Complex partial nephrectomy for multiple renal tumors, or multiplex partial nephrectomy, requires not only exceptional surgical skills but expertise of numerous nonsurgical methodologies, such as hands-on intraoperative ultrasonography and interpretation of multiple imaging modalities. In addition, multidisciplinary management is crucial for optimal outcomes in patient care. This review evaluates the most advanced surgical techniques and perioperative management required to successfully care for these challenging cases.

Multifocal epithelial tumors and field cancerization: stroma as a primary determinant

It is increasingly evident that cancer results from altered organ homeostasis rather than from deregulated control of single cells or groups of cells. This applies especially to epithelial cancer, the most common form of human solid tumors and a major cause of cancer lethality. In the vast majority of cases, in situ epithelial cancer lesions do not progress into malignancy, even if they harbor many of the genetic changes found in invasive and metastatic tumors. While changes in tumor stroma are frequently viewed as secondary to changes in the epithelium, recent evidence indicates that they can play a primary role in both cancer progression and initiation. These processes may explain the phenomenon of field cancerization, i.e., the occurrence of multifocal and recurrent epithelial tumors that are preceded by and associated with widespread changes of surrounding tissue or organ "fields."

Aerobic glycolysis: a novel target in kidney cancer

Renal cell carcinoma (RCC) is a heterogenous group of cancers that arise from the nephron. While there are distinct histologic subtypes associated with common genetic alterations, most forms of RCC are linked by a common pathway of dysregulated metabolism. Reliance on aerobic glycolysis, a feature of cancer first hypothesized by Warburg, is a common feature in sporadic and hereditary forms of kidney cancer. Two hereditary forms of RCC, succinate dehydrogenase (SDH) and hereditary leiomyomatosis and RCC (HLRCC), are characterized by mutations in Krebs cycle enzymes, rendering them dependent on glycolysis for energy requirements. The reliance on these pathways may make them vulnerable to novel metabolic strategies, including inhibition of glycolysis, glucose uptake and macromolecule biosynthesis.

Outcomes of patients with surgically treated bilateral renal masses and a minimum of 10 years of followup

PURPOSE

Nephron sparing surgery has been advocated for patients with bilateral renal masses but long-term functional and oncological outcomes are lacking. We report the outcomes of patients with bilateral renal masses and a minimum 10-year followup.

MATERIALS AND METHODS

Patients with bilateral renal masses evaluated at our institution who were treated with initial surgery at least 10 years ago and underwent interventions on each renal unit were included in the analysis. Collected data included demographics, hereditary diagnosis, number of renal interventions, renal function and mortality status. Overall and renal cell carcinoma specific survival was assessed. Comparisons were made of renal function and overall survival between groups with 2 renal units and a surgically solitary kidney.

RESULTS

A total of 128 patients met study inclusion criteria. Median followup in our cohort was 16 years (mean 17, range 10 to 49). The median number of surgical interventions was 3 (range 2 to 10). Of the patients 87 (68%) required repeat interventions on the ipsilateral renal unit at last followup with a median of 6.2 years (range 0.7 to 21) between interventions. Overall and renal cell cancer specific survival was 88% and 97%, respectively. Six patients (4.7%) ultimately underwent bilateral nephrectomy. Although renal function was better preserved in patients with 2 kidneys (70 vs 53 ml/minute/1.73 m(2), p = 0.0002), there was no difference in overall survival between those with bilateral kidneys or a surgically solitary kidney.

CONCLUSIONS

At a minimum 10-year followup after initial surgery, nephron sparing surgery allowed for excellent oncological and functional outcomes. Despite the need for repeat surgical interventions, nephron sparing surgery enabled dialysis to be avoided in more than 95% of patients.

Economic burden of repeat renal surgery on solitary kidney--do the ends justify the means? A cost analysis

PURPOSE

Despite the high morbidity of repeat renal surgery in patients with multifocal recurrent renal carcinoma, in most patients adequate renal function is preserved to obviate the need for dialysis. To our knowledge the economic burden of repeat renal surgery has not been evaluated. We provide a cost analysis for patients requiring repeat renal surgery on a solitary kidney.

MATERIALS AND METHODS

We reviewed the charts of patients treated at the National Cancer Institute who required repeat renal surgery from 1989 to 2010. Functional, oncological and surgical outcomes were evaluated and the costs of repeat renal surgery were calculated. We then compared costs in a cohort of 33 patients who underwent repeat renal surgery on a solitary kidney and in a hypothetical patient cohort treated with uncomplicated nephrectomy, fistula placement and dialysis. All costs were calculated based on Medicare reimbursement rates derived from CPT codes. Cost analysis was performed.

RESULTS

Despite a high 45% complication rate, 87% of patients maintained renal function that was adequate to avoid dialysis and 96% remained metastasis free at an average followup of 3.12 years (range 0.3 to 16.4). Compared to the hypothetical dialysis cohort, the financial benefit of repeat renal surgery was reached at 0.68 years.

CONCLUSIONS

Repeat renal surgery is a viable alternative for patients with multifocal renal cell carcinoma requiring multiple surgical interventions, especially when left with a solitary kidney. Despite the high complication rate, renal function is preserved in most patients and they have an excellent oncological outcome. The financial benefit of repeat renal surgery is reached at less than 1 year.

Repeat partial nephrectomy: surgical, functional and oncological outcomes

PURPOSE OF REVIEW

The greater utilization of partial nephrectomy and ablative procedures has increased the incidence of patients presenting with local renal recurrence. The choice to either perform a partial or radical nephrectomy in these situations can be a challenging decision.

RECENT FINDINGS

Repeat and salvage partial nephrectomy, while challenging and potentially associated with increased complications, offers patients the ability to maintain excellent renal functional outcomes and promising oncologic outcomes at intermediate follow-up.

SUMMARY

Surgeons should be familiar with the surgical complications and the functional and oncologic outcomes of reoperative nephron-sparing surgery (NSS). Recent data and outcome analysis support utilization of these procedures in patients presenting with either local recurrence or de-novo lesions in the ipsilateral kidney.

Feasibility and outcomes of partial nephrectomy for resection of at least 20 tumors in a single renal unit

PURPOSE

Patients with hereditary renal cancer are at increased risk for recurrent bilateral multifocal tumors and may require aggressive nephron sparing surgery to prevent renal replacement therapy. We evaluated feasibility and outcomes in patients who underwent partial nephrectomy with removal of at least 20 tumors in a single renal unit at 1 setting.

MATERIALS AND METHODS

We retrospectively reviewed the records of 30 patients who underwent a total of 34 partial nephrectomies with removal of at least 20 tumors at our institution from 1993 to 2008. Operative reports and hospital records were reviewed for perioperative data, and renal functional and oncologic outcomes. We compared preoperative and postoperative renal function with the 2-tailed t test.

RESULTS

There were no deaths and only 1 renal unit was lost. A median of 26.5 tumors was removed. Median estimated blood loss was 3,500 ml and median operative time was 9 hours. Perioperative complications developed in greater than 50% of cases. There was a statistically significant decrease in the estimated glomerular filtration rate at 3 months (67 vs 59 ml/minute/1.73 m(2), p < 0.001). Only 1 patient had metastatic disease. Eight of the 34 operated kidneys required subsequent intervention during the median followup of 52 months (range 4 to 187).

CONCLUSIONS

Aggressive partial nephrectomy to resect multiple tumors is technically feasible. There was a significant decrease in postoperative renal function but more than 80% of preoperative renal function was preserved in this cohort except in 1 patient. Also, oncologic outcomes were encouraging at intermediate term followup.