Staging of renal cell carcinoma: Current concepts.

The most important and widely utilized system for providing prognostic information following surgical management for renal cell carcinoma (RCC) is currently the tumor, nodes, and metastasis (TNM) staging system. An accurate and clinically useful staging system is an essential tool used to provide patients with counseling regarding prognosis, select treatment modalities, and determining eligibility for clinical trials. Data published over the last few years has led to significant controversies as to whether further revisions are needed and whether improvements can be made with the introduction of new, more accurate predictive prognostic factors. Staging systems have also evolved with an increase in the understanding of RCC tumor biology. Molecular tumor biomarkers are expected to revolutionize the staging of RCC by providing more effective prognostic ability over traditional clinical variables alone. This review will examine the components of the TNM staging system, current staging modalities including comprehensive integrated staging systems, and predictive nomograms, and introduce the concept of molecular staging for RCC.

Surveillance for renal cell carcinoma: why and how? When and how often?

Patient's history, physical examination, laboratory tests, and radiographic evaluation are the cornerstones of postoperative surveillance. It has been shown that localized renal cell carcinoma (RCC) can recur in nearly all organs of the body, but most commonly in the lung, bone, liver, brain, and renal fossa. Lung metastases can be sensitively detected through radiographic evaluation. Treatment of lung metastases might prolong survival, which supports surveillance x-ray or computed tomography scans. Surgical treatment of early detected liver metastases and local recurrences may also prolong survival, which supports a close abdominal surveillance program. Brain and bone metastases are usually symptomatic when they occur, and their treatment is generally palliative. Hence, surveillance protocols do not usually include their routine radiographic evaluation. Because partial nephrectomy does not increase the risk of local recurrence over radical nephrectomy, we recommend identical surveillance for completely resected tumors regardless of surgical approach. The risk of recurrence after nephrectomy is generally related to tumor stage, tumor grade, and patient performance status. The majority of recurrences occur within the first 5 years after surgery, supporting a more intense surveillance strategy within the first 5 years. The University of California Integrated Staging System (UISS) combines TNM stage, Fuhrman grade, and performance status, and categorizes patients into 3 different risk groups. The current surveillance protocol at our institution is based on the UISS. It is expected that molecular markers such as p53 will allow more individualized surveillance strategies in the future.

Importance of surgical margins in the management of renal cell carcinoma.

Surgical resection remains the standard treatment for clinically localized renal cell carcinoma. Pathological features of the surgical specimen, including the margin status, play an important part in determining the patient's prognosis. Negative surgical margins have traditionally been sought to maximize the efficacy of treatment. Initial concerns that partial nephrectomy might have high local recurrence rates compared with radical nephrectomy have now been minimized as a result of technological advances and refinements in surgical technique. Current concerns in relation to partial nephrectomy include the width of parenchymal tissue that should be removed to avoid positive surgical margins, effects of positive margins on recurrence-free survival, and the use of frozen-section analysis to determine margin status. Size of the surgical margin in partial nephrectomy does not seem to affect the risk of local tumor recurrence, and not all positive surgical margins lead to recurrent disease. Intraoperative frozen-section analysis is not definitive and its value in guiding the surgical management of renal tumors remains to be defined. Laparoscopic partial nephrectomy is emerging as an attractive approach for selected renal masses. Intraoperative use of ultrasound, cold-scissor parenchymal transection, embolization, and hilar clamping to achieve a bloodless operative field with clear visibility, may minimize the risk of positive margins during partial nephrectomy.

Flexible ureteroscopy and laser lithotripsy for single intrarenal stones 2 cm or greater--is this the new frontier?

PURPOSE: Percutaneous nephrolithotomy has been the standard of care for intrarenal calculi greater than 2 cm. Flexible ureteroscopy with holmium laser lithotripsy is a minimally invasive treatment modality that is able to treat large intrarenal calculi with the potential to decrease morbidity, while maintaining a high level of efficacy. MATERIALS AND METHODS: A total of 15 patients with a single intrarenal calculus 2 cm or greater were treated with retrograde ureteroscopic nephrolithotripsy. Lithotripsy was performed with a 7.2Fr flexible ureteroscope and 200 micron laser fiber. The stone-free rate was defined as the absence of any stones in the kidney or residual stone fragments less than 1 mm, which is too small to be extracted with a basket or a grasper. All patients underwent followup ureteroscopy within 15 days after the last procedure and renal ultrasound 30 days after the last treatment. RESULTS: There were a total of 15 intrarenal calculi 20 to 25 mm (mean 22) in diameter. The mean number of procedures was 2.3 (range 2 to 4). The overall stone-free rate was 93.3%. One patient (6.6%) had a residual 5 mm stone fragment in the lower pole of the kidney, which was followed expectantly for 2 years with no change in size. There were no major complications. There were 3 minor complications (20%), including 1 emergency room visit for fever and pain, and 2 cases of gross hematuria. All cases were performed on an outpatient basis. CONCLUSIONS: In select patients with a single intrarenal calculus 2 cm or greater small diameter flexible ureteroscopy with holmium laser lithotripsy may represent an alternative therapy to standard percutaneous nephrolithotomy with acceptable efficacy and low morbidity.

Prognostic factors and selection for clinical studies of patients with kidney cancer.

Over the past 2 decades, a greater understanding of the basic biology and genetics of kidney cancer has occurred. Surgical techniques have also evolved, and technological advances have made possible new methods of managing renal tumors. The most extensively used system to provide prognostic information for renal cell carcinoma (RCC) is currently the tumor, nodes, metastasis (TNM) staging system. Emerging data over the last few years has questioned whether further revisions are needed and if improvements can be made with the introduction of new, more accurate and predictive prognostic factors. The recent discovery of molecular tumor biomarkers are expected to revolutionize the staging of RCC and potentially lead to the development of new therapies based on molecular targeting. This review will examine the current staging modalities and prognostic factors associated with RCC as well as the selection of patients most likely to benefit from clinical trials.

In vivo efficacy of laparoscopic assisted percutaneous renal cryotherapy: evidence based guidelines for the practicing urologist.

PURPOSE: The treatment of small renal tumors continues to evolve in parallel with advances in ablative technology. We compared the lesion geometry of 3, 17 gauge cryoneedles to determine the most effective distance and configuration of the cryoneedles in an in vivo porcine kidney model. MATERIALS AND METHODS: Argon gas based renal cryoablation was performed in 6 pigs using a laparoscopically assisted percutaneous approach. Cryoablation using a single cryoneedle and a template of 3 cryoneedles with various ice ball shapes, including elliptical, bulb-shaped and standard 17 gauge cryoneedles (Galil Medical, Plymouth Meadow, Pennsylvania) was performed in 3 pigs. Three additional pigs underwent renal cryoablation using elliptical cryoneedles in 3 triangular template configurations with the cryoneedles spaced 1, 1.5 and 2 cm apart, respectively. The animals were sacrificed a minimum of 2 weeks following treatment. RESULTS: Elliptical cryoneedles achieved the largest area of necrosis when used in single and template configurations. When used in a template configuration of 3 needles 1, 1.5 and 2 cm apart from each other the calculated volume of necrosis was 4.3 x 4.5 x 2.5, 4.9 x 4.1 x 2.5 and 4.0 x 4.5 x 2.5 cm, respectively. CONCLUSIONS: Using a single 17 gauge cryoneedle is inadequate for treating most small renal tumors. Cryoneedles with an elliptical ice ball are most effective for achieving consistent and reliable tissue destruction. The 1.5 cm template configuration generated the largest area of necrosis. Our data suggest that with the current technology renal cryoablation should be limited to lesions not greater than 4 cm.

Laparoscopic heminephrectomy for upper-pole moiety in children using a 3-mm laparoscope and instruments.

PURPOSE: We report three cases of laparoscopic heminephrectomy in infants using a 3-mm laparoscope and instruments. To our knowledge, this is the first pediatric heminephrectomy series reported in the literature that utilized these small instruments. PATIENTS AND METHODS: Three pediatric patients underwent laparoscopic heminephrectomy for an upper-pole moiety in a duplicated collecting system with 3-mm laparoscopic ports and a 3-mm Storz 30 degrees laparoscope. RESULTS: All three cases were completed laparoscopically with total times of 120, 135, and 160 minutes. There were no intraoperative complications, and there was minimal blood loss. The optics of the laparoscope provided visibility and illumination similar to those available with larger-diameter laparoscopes. Two patients were discharged approximately 1 day postoperatively. The third patient required intravenous antibiotics to treat a urinary-tract infection and was discharged home 4 days postoperatively. All three patients had recovered fully by 2 weeks. CONCLUSION: The 3-mm laparoscope provides excellent visibility and illumination for performing heminephrectomy in the pediatric population. In addition, the 3-mm instruments provide excellent tissue handling, similar to that of the 5-mm tools.

Unclassified renal cell carcinoma: an analysis of 85 cases.

OBJECTIVES: To compare cancer-specific mortality in patients with unclassified renal cell carcinoma (URCC) vs clear cell RCC (CRCC) after nephrectomy, as URCC is a rare but very aggressive histological subtype. PATIENTS AND METHODS: Eighty-five patients with URCC and 4322 with CRCC were identified within 6530 patients treated with either radical or partial nephrectomy at 18 institutions. Of 85 patients with URCC, 55 were matched with 166 of 4322 for grade, tumour size, and Tumour, Node and Metastasis stages. Kaplan-Meier and life-table analyses were used to address RCC-specific survival. Subsequently, multivariate Cox regression analyses were used to test for differences in RCC-specific survival in unmatched samples. RESULTS: Of patients with URCC, 80% had Fuhrman grades III or IV, vs 37.8% for CRCC. Moreover, 36.5% of patients with URCC had pathologically confirmed nodal metastases, vs 8.6% with CRCC. Finally, 54.1% of patients with URCC had distant metastases at the time of nephrectomy, vs 16.8% with CRCC. Despite these differences in the overall analyses, after matching for tumour characteristics, the URCC-specific mortality rate was 1.6 times higher (P = 0.04) in matched analyses and 1.7 times higher (P = 0.001) in multivariate analyses. CONCLUSIONS: These findings indicate that URCC presents with a higher stage and grade, and even after controlling for the stage and grade differences, predisposes patients to 1.6-1.7 times the mortality of CRCC.

Patterns of recurrence and surveillance strategies for renal cell carcinoma following surgical resection.

Renal cell carcinoma (RCC) remains one of the most lethal urologic malignancies, with up to 40% of patients eventually dying of cancer progression. Despite advances in the diagnosis, staging and treatment of patients with RCC, approximately a third of patients who undergo surgery for clinically localized RCC will suffer a recurrence. Timely identification of recurrences following surgical extirpation is imperative in the treatment of these patients. RCC is known to metastasize through hematogenous routes of spread to distant organ sites and via lymphatic channels to regional lymph nodes. The path of tumor escape is associated with diverse clinical outcomes and a unique tumor biology. A consensus on surveillance regimens for patients following surgical resection of localized disease is lacking. The most extensively used system for providing prognostic information regarding survival and recurrence of disease has historically been the tumor-node-metastasis (TNM) classification system. As a result, most contemporary surveillance protocols have tailored follow-up regimens according to stage-based stratifications. Numerous studies have recently demonstrated that certain clinical and histopathological factors can improve the prediction of tumor recurrence. The incorporation of these prognostic factors into stage-based stratification models should be better than stage alone in attempting to provide a rational approach to identifying treatable recurrences while minimizing unnecessary exams and tests, as well as patient anxiety. Advances in the understanding of the pathogenesis, behavior and molecular biology of RCC have paved the way for developments that may enhance early diagnosis and prognostication, and improve survival for patients. Lastly, molecular markers should, in the future, revolutionize surveillance protocols for RCC by tailoring follow-up to specific molecular classifications.

Metachronous bilateral renal cell carcinoma: risk assessment, prognosis and relevance of the primary-free interval.

PURPOSE: We evaluated the prognosis, risk factors and relevance of the primary-free interval in a large cohort with metachronous bilateral renal cell carcinoma. MATERIALS AND METHODS: We studied 120 patients with metachronous, bilateral renal cell carcinoma who were treated at 12 international academic centers. Logistic regression was performed to evaluate risk factors for contralateral metachronous renal cell carcinoma during followup. Disease specific survival was evaluated with univariate and multivariate analysis. RESULTS: Median age at diagnosis of the first and second renal cell carcinomas was 54 and 62 years, respectively. The most common histological subtype was bilateral clear cell renal cell carcinoma (89% of cases). Familial renal cell carcinoma was found in 14% of patients, von Hippel-Lindau disease was found in 4% and nonfamilial renal cell carcinoma was found in 81%. The 15-year disease specific survival rates for the first and second renal cell carcinomas were 66% and 44%, respectively. Logistic regression revealed von Hippel-Lindau disease, a family history of renal cell carcinoma, multifocal first renal cell carcinoma and young patient age as independent risk factors for contralateral renal cell carcinoma after surgery for unilateral renal cell carcinoma. A longer primary-free interval was associated with a better prognosis. When calculating disease specific survival from the diagnosis of the first renal cell carcinoma, the primary-free interval was an independent prognostic factor. CONCLUSIONS: Long-term survival rates of metachronous, bilateral renal cell carcinoma are moderate. von Hippel-Lindau disease, a family history of renal cell carcinoma, multifocal first renal cell carcinoma and young patient age are independent risk factors for contralateral renal cell carcinoma. These risk factors support close and extended abdominal surveillance following nephrectomy for unilateral renal cell carcinoma. Patients with a longer primary-free interval have a more favorable prognosis.

Prognostic impact of tumor size on pT2 renal cell carcinoma: an international multicenter experience.

PURPOSE: The current tumor classification for renal cell carcinoma classifies pT2 tumors as larger than 7 cm in greatest dimension and limited to the kidney. We examined the current pT2 tumor classification of renal cell carcinoma and determined whether a tumor size cutoff exists that would improve prognostic accuracy. MATERIALS AND METHODS: We studied 706 patients with pT2 renal cell carcinoma treated with surgical extirpation at 9 international academic centers. Data collected from each patient included age at diagnosis, gender, 2002 TNM (tumor, node, metastasis) stage, tumor size, nuclear grade, performance status, histological subtype and disease specific survival. Disease specific survival was evaluated with univariate and multivariate analysis. RESULTS: Median followup was 52 months. Univariate Cox regression analysis showed a significant association of tumor size with disease specific survival (HR 1.11, p<0.001). An ideal tumor size cutoff of 11 cm was identified, which led to the stratification of 2 groups with respect to disease specific survival (p<0.0001) with 5 and 10-year survival rates of 73% and 65% for pT2 11 cm or less, and 57% and 49% for pT2 larger than 11 cm, respectively. The incidence of metastases was significantly greater in the larger than 11 cm group, while Eastern Cooperative Oncology Group performance status, Fuhrman grade and histological subtype were similar. Multivariate Cox regression analysis retained tumor size as an independent prognostic factor and as the strongest prognostic factor for patients with pT2N0M0 disease. CONCLUSIONS: Our data suggest that the current pT2 classification can be improved by subclassification into pT2a and pT2b based on a tumor size cutoff of 11 cm. Patients in the proposed pT2bN0M0 group are at higher risk for death from renal cell carcinoma and should be considered for adjuvant therapies. External validation is warranted before suggesting change to the TNM classification.

Platelet count and preoperative haemoglobin do not significantly increase the performance of established predictors of renal cell carcinoma-specific mortality.

OBJECTIVE: Anaemia and/or thrombocytosis were identified as independent predictors of poor survival in renal cell carcinoma (RCC). We tested the extent to which these markers worsen the prognosis in these patients. METHODS: Analyses targeted 1828 patients with renal cell carcinoma. Univariable, multivariable, and predictive accuracy analyses addressed RCC-specific mortality (RCC-SM). RESULTS: In univariable and multivariable analyses, both platelet count and preoperative haemoglobin level were statistically significant predictors of RCC-SM. However, neither platelet count nor preoperative haemoglobin level increased the combined multivariable accuracy of established RCC-SM (predictive accuracy gain=0.3%) predictors. CONCLUSIONS: Patients who present with severe anaemia or elevated platelets are at no higher risk of RCC-SM than that related to their stage, grade, histologic subtype, and Eastern Cooperative Oncology Group-Performance Status.

Ureteropelvic junction obstruction.

PURPOSE: We quantified the burden of ureteropelvic junction obstruction in the United States by identifying trends in the use of health care resources and estimating the economic impact of the disease. MATERIALS AND METHODS: The analytical methods used to generate these results were described previously. RESULTS: Inpatient hospitalization rates were highest in children younger than 3 years. Most patients were male and hospitalizations occurred almost exclusively at urban centers. Patients with a primary diagnosis of ureteropelvic junction obstruction between 1994 and 2000 had an overall decrease in the age adjusted rate of inpatient hospitalization from 1.1/100,000 to 0.8/100,000. Physician office visits by Medicare beneficiaries with ureteropelvic junction obstruction as the primary diagnosis showed stable overall age adjusted rates during the reported years. Between 1999 and 2003 mean inpatient length of stay and cost per child hospitalized with the primary diagnosis of ureteropelvic junction obstruction was 2.9 days and $7,728, respectively. Average length of stay decreased more for children than for adults but total inpatient spending remained stable at about $12 million. CONCLUSIONS: The majority of ureteropelvic junction obstructions are diagnosed in the perinatal period. Surgical intervention for pediatric patients has decreased with time, while there has been an increasing trend toward the conservative management of this condition.

Clinicopathological features and prognosis of synchronous bilateral renal cell carcinoma: an international multicentre experience.

OBJECTIVE: To present a multicentre experience and the largest cohort to date of nonmetastatic (N0M0) synchronous bilateral renal cell carcinoma (RCC), as because it is rare the single-institutional experience is limited. PATIENTS AND METHODS: We retrospectively studied 10 337 patients from 12 urological centres to identify patients with N0M0 synchronous bilateral RCC; the clinicopathological features and cancer-specific survival were compared to a cohort treated for N0M0 unilateral RCC. RESULTS: In all, 153 patients had synchronous bilateral solid renal tumours, of whom 135 (88%) had synchronous bilateral RCC, 118 with nonmetastatic disease; 91% had nonfamilial bilateral RCC. Bilateral clear cell RCC was the major histological subtype (76%), and papillary RCC was the next most frequent (19%). Multifocality was found in 54% of bilateral RCCs. Compared with unilateral RCC, patients did not differ in Eastern Cooperative Oncology Group performance status (ECOG PS) and T classification, but bilateral RCCs were more frequently multifocal (54% vs 16%, P < 0.001) and of the papillary subtype (19% vs 12%), and less frequently clear cell RCC (76% vs 83%, P = 0.005). For the outcome, patients with nonmetastatic synchronous bilateral RCC and unilateral RCC had a similar prognosis (P = 0.63); multifocality did not affect survival (P = 0.60). Multivariate analysis identified ECOG PS, T classification, and Fuhrman grade, but not laterality, as independent prognostic factors for cancer-specific survival. CONCLUSIONS: Patients with N0M0 synchronous bilateral RCC and N0M0 unilateral RCC have a similar prognosis. The frequency of a familial history for RCC (von Hippel-Lindau disease or familial RCC) was significantly greater in bilateral synchronous than in unilateral RCC. The significant pathological findings in synchronous bilateral RCC are papillary subtype and multifocality.

Use of haemostatic agents and glues during laparoscopic partial nephrectomy: a multi-institutional survey from the United States and Europe of 1347 cases.

OBJECTIVES: Laparoscopic partial nephrectomy (LPN) is a technically challenging procedure for the management of renal tumours. Major complications of LPN include bleeding and urine leakage. Haemostatic agents (HAs) and/or glues may reduce haemorrhage and urine leakage. We sought to examine the current practice patterns for urologists performing LPN with regard to HA use and its relationship with bleeding and urine leakage. MATERIALS AND METHODS: A survey was sent via e-mail to urologists currently performing LPN in centres in the United States and Europe. We queried the indications for HA/glue usage, type of HAs/glues used, and whether concomitant suturing/bolstering was performed. In addition, the total number of LPNs performed, laparoscopic tools used to resect the tumour, tumour size, and tumour position were queried. RESULTS: Surveys suitable for analysis were received from 18 centres (n=1347 cases). HAs and/or glues were used in 1042 (77.4%) cases. Mean tumour size was 2.8cm, with 79% of the tumours being defined as exophytic and 21% deep. The HAs and glues used included gelatin matrix thrombin (FloSeal), fibrin gel (Tisseel), bovine serum albumin (BioGlue), cyanoacrylate glue (Glubran), oxidized regenerated cellulose (Surgicel), or combinations of these. Sixteen centres performed concomitant suturing/bolstering. The overall postoperative bleeding requiring transfusion and urine leakage rates were 2.7% and 1.9%, respectively. CONCLUSIONS: The use of HAs and/or glues is routine in most centres performing LPN. The overall haemorrhage and urine leakage rates are low following LPN. More studies are needed to assess the potential role of HAs and/or glues in LPN.

Prognostic relevance of tumour size in T3a renal cell carcinoma: a multicentre experience.

OBJECTIVE: To evaluate the prognostic role of tumour size in pathological stage T3a renal cell carcinoma (RCC) with fat invasion only and to assess whether this subgroup maintains its relevance over the other pathological stages. METHODS: We retrospectively studied 2113 patients from eight international institutions who were treated by surgical resection for T2-4 RCC. Disease-specific survival (DSS) was evaluated with univariate and multivariate analyses. RESULTS: Univariate analysis of patients with T3a RCC showed that tumour size was significantly associated with DSS (HR: 1.09, 95% CI: 1.05-1.12, p<0.001). An ideal cut-off of 7 cm for these patients was identified with a scatter plot of Martingale residuals and tumour size. The two T3a groups were distinctly different with respect to clinicopathologic parameters (performance status, metastases, grade, histological subtype) and survival (p<0.001). Median survival time was not reached for patients with T2 and T3a< or =7 cm disease with a 5- and 10-yr DSS rate of 70% and 59% and 63% and 53%, respectively. Median survival time for patients with T3a>7 cm, T3b, T3c, and T4 disease was 54, 46, 21, and 11 mo, respectively, with 5- and 10-yr DSS rates of 46% and 36%, 46% and 36%, 34% and 0%, and 16% and 14%, respectively. CONCLUSIONS: Our data indicate that tumour size is an important factor for predicting outcome of patients with T3a RCC with fat invasion only. Our findings should merit consideration during the next revision of the TNM classification.