Lessons learned in the surgical management of renal cell carcinoma

Application of Hypothermic Perfusion via a Renal Artery Balloon Catheter During Robot-assisted Partial Nephrectomy and Effect on Renal Function

RATIONALE OBJECTIVES

To assess the feasibility, safety, and effect of hypothermic perfusion on postoperative renal function employing a renal artery balloon catheter inserted via robot-assisted partial nephrectomy (h-RAPN) to treat renal tumors.

MATERIALS AND METHODS

Forty-three patients with renal tumors were studied between March 2013 and August 2017. Renal artery balloon catheters were placed under angiographic guidance, and the balloon was fully inflated to occlude the renal artery during surgery. After establishing venous outflow, a robot-assisted partial nephrectomy was performed following perfusion with sodium lactate Ringer's solution at 4°C through the balloon catheter. Renal dynamic imaging was used to assess renal function, with calculation units consisting of glomerular filtration rate per unit volume of the kidney (GFR-UV).

RESULTS

Six patients were converted to radical nephrectomy intraoperatively, and the remaining 37 patients successfully underwent the h-RAPN procedure. Two patients had incomplete occlusion of the renal artery and received supplementary arterial clamp occlusion intraoperatively. One patient's balloon catheter slipped out of position preoperatively, and the patient was returned to the interventional radiology suite for balloon reinsertion, after which the patient underwent surgery successfully. No patients had severe complications. The average cold ischemia time was 39.5 ± 9.7 min (range, 22-123 min), the average temperature of the affected kidney during surgery was 19.3 ± 3.5°C (17.2-26.7°C), the average postoperative GFR-UV of the affected kidney was 0.42 ± 0.09 ml/min/ml (0.21-1.24 ml/min), and the average postoperative GFR-UV of the healthy kidney was 0.30 ± 0.04 ml/min/ml (P > 0.05). Multiple regression analysis indicated that cold ischemia time was an independent risk factor affecting the postoperative GFR of the affected kidney.

CONCLUSION

The advantages of h-RAPN include a clear surgical field enabling precise resection. When hypothermic perfusion via a renal artery balloon catheter is performed in conjunction with h-RAPN, the surgical time can be lengthened without increasing impairment of the affected kidney function, making this a safe and effective method of treating kidney tumors.

Economic evaluation of first-line treatments for metastatic renal cell carcinoma: a cost-effectiveness analysis in a health resource-limited setting

Background

To estimate, from the perspective of the Chinese healthcare system, the economic outcomes of five different first-line strategies among patients with metastatic renal cell carcinoma (mRCC).

Methods and Findings

A decision-analytic model was developed to simulate the lifetime disease course associated with renal cell carcinoma. The health and economic outcomes of five first-line strategies (interferon-alfa, interleukin-2, interleukin-2 plus interferon-alfa, sunitinib and bevacizumab plus interferon-alfa) were estimated and assessed by indirect comparison. The clinical and utility data were taken from published studies. The cost data were estimated from local charge data and current Chinese practices. Sensitivity analyses were used to explore the impact of uncertainty regarding the results. The impact of the sunitinib patient assistant program (SPAP) was evaluated via scenario analysis. The base-case analysis showed that the sunitinib strategy yielded the maximum health benefits: 2.71 life years and 1.40 quality-adjusted life-years (QALY). The marginal cost-effectiveness (cost per additional QALY) gained via the sunitinib strategy compared with the conventional strategy was $220,384 (without SPAP, interleukin-2 plus interferon-alfa and bevacizumab plus interferon-alfa were dominated) and $16,993 (with SPAP, interferon-alfa, interleukin-2 plus interferon-alfa and bevacizumab plus interferon-alfa were dominated). In general, the results were sensitive to the hazard ratio of progression-free survival. The probabilistic sensitivity analysis demonstrated that the sunitinib strategy with SPAP was the most cost-effective approach when the willingness-to-pay threshold was over $16,000.

Conclusions

Our analysis suggests that traditional cytokine therapy is the cost-effective option in the Chinese healthcare setting. In some relatively developed regions, sunitinib with SPAP may be a favorable cost-effective alternative for mRCC.

Identification of the primary tumour with the help of diffusion-weighted MRI in a patient with autosomal dominant polycystic kidney disease and metastatic renal cell carcinoma

We report the case of a 47-year-old patient with autosomal dominant polycystic kidney disease, who became symptomatic owing to a painful metastasis of a renal cell carcinoma. Abdominal sonography, multiphase CT and MRI were performed in order to localise and resect the primary tumour, but its identification was severely hampered owing to multiple renal cysts. In addition to standard MRI protocol, a spin-echo, single-shot echo planar diffusion-weighted imaging sequence was performed. The mean apparent diffusion coefficient (ADC) of renal cysts was 2.66±0.12 × 10(-3) mm(2) s(-1), 1.76±0.19 × 10(-3) mm(2) s(-1) of renal parenchyma in and 1.26±0.18 × 10(-3) mm(2) s(-1) of a suspicious soft-tissue mass at the midsection of the right kidney, indicating an area of higher cellularity. This value was significant lower than the ADC obtained for renal parenchyma (p<0.0001). Right-sided nephrectomy was performed and the pathological diagnosis of the suspicious lesion was clear cell renal carcinoma.

Molecular analysis of tumor margins by MALDI mass spectrometry in renal carcinoma

The rate of tumor recurrence post resection suggests that there are underlying molecular changes in nearby histologically normal tissue that go undetected by conventional diagnostic methods that utilize contrast agents and immunohistochemistry. MALDI MS is a molecular technology that has the specificity and sensitivity to monitor and identify molecular species indicative of these changes. The current study utilizes this technology to assess molecular distributions within a tumor and adjacent normal tissue in clear cell renal cell carcinoma biopsies. Results indicate that the histologically normal tissue adjacent to the tumor expresses many of the molecular characteristics of the tumor. Proteins of the mitochondrial electron transport system are examples of such distributions. This work demonstrates the utility of MALDI MS for the analysis of tumor tissue in the elucidation of aberrant molecular changes in the tumor microenvironment.

Imaging of advanced renal cell carcinoma

OBJECTIVES

To describe current radiological cross-sectional imaging in the detection and staging of advanced renal cell carcinoma (RCC), defined here as RCC reaching beyond the renal capsule, whether by immediate extension or by metastasis.

METHODS

Review and summary of current radiological and urological literature, including original articles and reviews, retrieved from the medical data base "PubMed".

RESULTS

Multi-detector-row computed tomography (MDCT) shows a sensitivity of up to 100% and specificity of about 90% for retroperitoneal disease, venous tumour thrombus, and metastasis, but limited accuracy for lymphadenopathy in RCC. Magnetic resonance imaging (MRI) is applied as a problem-solving modality, with particular strength in imaging metastasis to brain and bone. However, dynamic, contrast-enhanced- (DCE-) and arterial-spin-labelling (ASL-) MRI may help to monitor early response to angiogenesis inhibitor drugs. Ultrasonography (US) shows limited capability of identifying retroperitoneal disease, venous tumour thrombus extension, and metastasis. Positron Emission Tomography with 18-fluoro-desoxy-glucose (FDG-PET) demonstrates modest accuracy for metastasis of RCC, with positive studies being suspicious, while negative studies cannot reliably exclude disease.

CONCLUSIONS

MDCT represents the diagnostic mainstay for the detection and staging of RCC. In the wake of new systemic therapies for advanced RCC, including angiogenesis inhibitor drugs, monitoring treatment response may become a new task for cross-sectional imaging.

Direct tissue analysis by matrix-assisted laser desorption ionization mass spectrometry: application to kidney biology

Direct tissue analysis using matrix-assisted laser desorption ionization mass spectrometry (MALDI MS) provides in situ molecular analysis of a wide variety of biological molecules including xenobiotics. This technology allows measurement of these species in their native biological environment without the use of target-specific reagents such as antibodies. It can be used to profile discrete cellular regions and obtain region-specific images, providing information on the relative abundance and spatial distribution of proteins, peptides, lipids, and drugs. In this article, we report the sample preparation, MS data acquisition and analysis, and protein identification methodologies used in our laboratory for profiling/imaging MS and how this has been applied to kidney disease and toxicity.

Staging of renal cell carcinoma

As in other malignant tumors, prognosis in renal cell carcinoma (RCC) depends on tumor extent and metastasis at the time of primary diagnosis. Staging systems formalize the way in which the extent of RCC is being described and classified. Primary staging of RCC aims at evaluating surgical options. Since surgical excision, which is the mainstay of therapy in non-metastatic RCC, and, recently, minimally invasive ablation methods have evolved significantly over the last decades, staging systems continue to evolve along the way. The 40-year-old Robson classification has been replaced with the TNM classification of RCC, because the latter adapts more easily to changing patterns of diagnosis and therapy. Modern cross-sectional imaging methods, such as multidetector-row computed tomography (MDCT), and magnetic resonance imaging (MRI), perform highly in T-staging of local tumor extent and M-staging of distant metastasis. However, both MDCT and MRI perform poorly in N-staging of lymphadenopathy. At present, 18-F-desoxy-glucose positron emission tomography (FDG-PET) appears to be unreliable in the detection of RCC and its metastasis. This overview of current radiological and surgical literature attempts to describe how modern staging systems for RCC are organized, and which radiological and surgical developments currently influence the way in which primary staging and prognosis of RCC depend on one another.

In Vivo Assessment of Radio Frequency Induced Thermal Damage of Kidney Using Optical Spectroscopy

PURPOSE

Radio frequency ablation is a promising modality for treating small renal tumors. Several studies have been published showing its efficacy. A major drawback in the current management of renal tumors with radio frequency ablation is the lack of an effective modality to accurately monitor the progress of the ablation zone in real-time fashion. Previous studies have demonstrated the feasibility of using optical spectroscopy to assess tissue thermal damage, especially in hepatic lesions. We examined the feasibility of this technology in the setting of renal radio frequency ablation.

MATERIALS AND METHODS

A portable spectroscopic system was used to acquire in vivo fluorescence and diffuse reflectance spectra from porcine renal tissue undergoing radio frequency ablation in real-time fashion with simultaneous temperature recordings. Fluorescence and diffuse reflectance spectral data were then correlated with various degrees of thermal damage and temperature recordings.

RESULTS

The most noticeable change in fluorescence characteristics of renal tissue resulting from thermal coagulation was a strong decrease in fluorescence intensity between 400 and 550 nm. When fully coagulated, a significant increase in diffuse reflectance intensity was observed between 500 and 800 nm.

CONCLUSIONS

Optical spectroscopy, specifically fluorescence and diffuse reflectance spectroscopy, differs significantly in porcine renal tissues with varying degrees of thermal damage from radio frequency ablation in an in vivo setting. Future clinical studies with sufficient sample size are required to validate the potential of these findings. Optical diagnostics may prove to be a rapid, noninvasive, low cost option for monitoring the tumor response to radio frequency based ablative techniques. It may be integrated into future radio frequency ablation probes.

Biologic significance of fascin expression in clear cell renal cell carcinoma: systematic analysis of primary and metastatic tumor tissues using a tissue microarray technique

OBJECTIVES

To investigate the biologic significance of fascin, a globular actin cross-linking protein, involved in cell adhesion and motility, in primary and metastatic renal cell carcinoma (RCC).

METHODS

A total of 136 primary clear cell RCCs and 54 clear cell RCC metastases were stained immunohistochemically using a tissue microarray technique. Distinct cytoplasmic staining was considered positive, and the staining results were associated with the pT stage, Fuhrman grade, tumor size, sarcomatoid morphology, and metastasis-free survival. For multivariate testing, Cox's proportional hazards regression model was used.

RESULTS

Fascin expression was noted in 13 (10%) of 136 primary and 25 (46%) of 54 metastatic RCC specimens (P <0.001). Fascin expression was associated with high tumor stage (2 [3%] of 70 pT1 versus 11 [17%] of pT2/pT3; P = 0.008), high tumor grade (3 [3%] of 88 grade 1-2 versus 10 [21%] of 48 grade 3-4; P = 0.002), and large tumor size (P <0.001). In addition, 8 (62%) of 13 RCCs with sarcomatoid morphology expressed fascin compared with 5 (4%) of 123 RCCs without sarcomatoid transformation (P <0.001). Metastatic disease was noted in 10 (77%) of 13 patients with fascin-positive RCC compared with 26 (21%) of 121 patients with fascin-negative RCC (P <0.001). Multivariate analysis revealed pT Stage 1 or greater (P <0.001, risk ratio [RR] 8.6, 95% confidence interval [CI] 2.8 to 26.5), Fuhrman grade greater than 2 (P <0.001, RR 12.7, 95% CI 4.6 to 35.4), fascin expression (P <0.001, RR 7.2, 95% CI 3.0 to 17.4), and female gender (P = 0.02, RR 2.5, 95% CI 1.1 to 5.5) as independent predictors of metastatic disease.

CONCLUSIONS

Fascin immunoreactivity in RCC proved to be an independent predictor of metastatic disease and was demonstrated in almost one half of RCC metastases. Thus, fascin may be a promising molecular target for future cancer therapy.