Importance of surgical margins in the management of renal cell carcinoma

Discrimination between human normal renal tissue and renal cell carcinoma by dielectric properties using in-vitro BIA

Renal cell carcinoma (RCC) poses a serious threat to human health, which urgently requires a method that can quickly distinguish between human normal renal tissue (NRT) and RCC for the purpose of accurate detection in clinical practice. The significant difference in cell morphology between NRT and RCC tissue underlies the great potential of the bioelectrical impedance analysis (BIA) to distinguish two types of human tissues. The study aims to achieve such discrimination through comparison of their dielectric properties within the frequency range from 10 Hz to 100 MHz. The dielectric properties of 69 cases of human normal and cancer renal tissue were measured 15 min after tissue isolation in a strictly controlled environment (37°C, 90% humidity). In addition to the impedance parameters (resistivity, conductivity and relative permittivity), the characteristic parameters extracted from the Cole curve were also compared between NRT and RCC. Furthermore, a novel index, distinguishing coefficient (DC), was used to obtain the optimal frequency for discrimination between NRT and RCC. In terms of impedance parameters, the RCC conductivity at low frequencies (<1 kHz) was about 1.4 times as large as that of NRT, and its relative permittivity was also significantly higher (p < 0.05). In terms of characteristic parameters, two characteristic frequencies (14.1 ± 1.1 kHz and 1.16 ± 0.13 MHz) were found for NRT while only one for RCC (0.60 ± 0.05 MHz). A significant difference of low-frequency resistance (R0) between RCC and NRT was also observed (p < 0.05). As for the new index DC, relative permittivity DCs below 100 Hz and at around 14 kHz were both greater than 1. These findings further confirm the feasibility of discrimination between RCC and NRT and also provide data in favor of further clinical study of BIA to detect the surgical margins.

A survey of augmented reality methods to guide minimally invasive partial nephrectomy

INTRODUCTION

Minimally invasive partial nephrectomy (MIPN) has become the standard of care for localized kidney tumors over the past decade. The characteristics of each tumor, in particular its size and relationship with the excretory tract and vessels, allow one to judge its complexity and to attempt predicting the risk of complications. The recent development of virtual 3D model reconstruction and computer vision has opened the way to image-guided surgery and augmented reality (AR).

OBJECTIVE

Our objective was to perform a systematic review to list and describe the different AR techniques proposed to support PN.

MATERIALS AND METHODS

The systematic review of the literature was performed on 12/04/22, using the keywords "nephrectomy" and "augmented reality" on Embase and Medline. Articles were considered if they reported surgical outcomes when using AR with virtual image overlay on real vision, during ex vivo or in vivo MIPN. We classified them according to the registration technique they use.

RESULTS

We found 16 articles describing an AR technique during MIPN procedures that met the eligibility criteria. A moderate to high risk of bias was recorded for all the studies. We classified registration methods into three main families, of which the most promising one seems to be surface-based registration.

CONCLUSION

Despite promising results, there do not exist studies showing an improvement in clinical outcomes using AR. The ideal AR technique is probably yet to be established, as several designs are still being actively explored. More clinical data will be required to establish the potential contribution of this technology to MIPN.

Emerging applications of nanobodies in cancer therapy

Cancer is a heterogeneous disease, requiring treatment tailored to the unique phenotype of the patient's tumor. Monoclonal antibodies (mAbs) and variants thereof have enabled targeted therapies to selectively target cancer cells. Cancer cell-specific mAbs have been used for image-guided surgery and targeted delivery of radionuclides or toxic agents, improving classical treatment strategies. Cancer cell-specific mAbs can further inhibit tumor cell growth or can stimulate immune-mediated destruction of cancer cells, a feature that has also been achieved through mAb-mediated manipulation of immune cells and pathways. Drawbacks of mAbs and their variants, together with the discovery of camelid heavy chain-only antibodies and the many advantageous features of their variable domains, referred to as V_HHs, single domain antibodies or nanobodies (Nbs), resulted in the exploration of Nbs as an alternative targeting moiety. We therefore review the state-of-the-art as well as novel exploitation strategies of Nbs for targeted cancer therapy.

A generative adversarial approach to facilitate archival-quality histopathologic diagnoses from frozen tissue sections

In clinical diagnostics and research involving histopathology, formalin-fixed paraffin-embedded (FFPE) tissue is almost universally favored for its superb image quality. However, tissue processing time (>24 h) can slow decision-making. In contrast, fresh frozen (FF) processing (<1 h) can yield rapid information but diagnostic accuracy is suboptimal due to lack of clearing, morphologic deformation and more frequent artifacts. Here, we bridge this gap using artificial intelligence. We synthesize FFPE-like images ("virtual FFPE") from FF images using a generative adversarial network (GAN) from 98 paired kidney samples derived from 40 patients. Five board-certified pathologists evaluated the results in a blinded test. Image quality of the virtual FFPE data was assessed to be high and showed a close resemblance to real FFPE images. Clinical assessments of disease on the virtual FFPE images showed a higher inter-observer agreement compared to FF images. The nearly instantaneously generated virtual FFPE images can not only reduce time to information but can facilitate more precise diagnosis from routine FF images without extraneous costs and effort.

Emerging Intraoperative Imaging Technologies in Urologic Oncology

As surgical cases become more complex, intraoperative imaging is increasingly being used. This article discusses emerging imaging technologies used in prostate, kidney, and bladder cancer surgery, including ultrasound, fluorescence-based, and enhanced endoscopy techniques including their strengths and limitations.

A pre-screening strategy to assess resected tumor margins by imaging cytoplasmic viscosity and hypoxia

To assure complete tumor removal, frozen section analysis is the most common procedure for intraoperative pathological assessment of resected tumor margins. However, during one operation, multiple biopsies may be sent for examination, but only few of them are made into cryosections because of the complex preparation protocols and time-consuming pathological analysis, which potentially increases the risk of overlooking tumor involvement. Here, we propose a fluorescence-based pre-screening strategy that allows high-throughput, convenient, and fast gross assessment of resected tumor margins. A dual-activatable cationic fluorescent molecular rotor was developed to specifically illuminate live tumor cells’ cytoplasm by emitting two different fluorescence signals in response to elevations in hypoxia-induced nitroreductase (a biochemical marker) and cytoplasmic viscosity (a biophysical marker), two characteristics of cancer cells. The ability of the fluorescent molecular rotor in detecting tumor cells was evaluated in mouse and human specimens of multiple tissues by comparing with hematoxylin and eosin staining. Importantly, the fluorescent molecular rotor achieved 100 % specificity in discriminating lung and liver cancers from normal tissue, allowing pre-screening of the tumor-free surgical margins and promoting clinical decision. Altogether, this type of fluorescent molecular rotor and the proposed strategy may serve as a new option to facilitate intraoperative assessment of resected tumor margins.

Management of colon-invading renal cell carcinoma: Operative technique and systematic review

Invasion into adjacent organs by non-metastatic renal cell carcinoma (RCC) occurs in 1% of patients suitable for resection. Colonic invasion is rare and presents technical challenges. No prospective data exists to guide management of these patients. We present the first reported case of a colon-invading RCC managed with simultaneous open right radical nephrectomy and extended right hemicolectomy. PubMed, Scopus and EMBASE databases were searched for relevant case reports reporting management of colon-invading renal cell carcinoma. Case reports, case series and cohort studies were eligible. A chart review was performed on a patient who presented with right-sided colon-invading RCC. Four previously reported cases were identified. The current case was managed with simultaneous open radical nephrectomy and extended right hemicolectomy. The patient remains well six months postoperatively with no evidence of disease recurrence. Histopathological evaluation of the resected specimen confirmed a T4 clear cell RCC with sarcomatoid differentiation. Colon-invading RCC is rare. This is the first reported case of right-sided, colon-invading RCC treated with radical resection. The current case confirms radical resection is a feasible management strategy for similar presentations. En bloc resection of involved organs remains the only potentially curative option for locally advanced disease.

Positive margins after partial nephrectomy in renal cell carcinoma: Oncological outcomes of conservative management after long-term follow-up

INTRODUCTION

Partial nephrectomy (PN) is the standard treatment for small and localized kidney tumours (cT1). One of the controversial aspects regarding this technique is the management of affected/positive resection margins. We present the long-term oncological results in patients with PSM after PN managed conservatively.

MATERIAL AND METHODS

There were 207 PN performed in our centre between 1990 and 2011. 17 patients presented PSM. 2 patients were excluded from the study due to completion nephrectomy afterwards. Follow-up was was done with abdominal contrast-enhanced computed tomography every 6 months for the first 2 years and subsequently, once a year. Cancer-specific survival and disease-free survival were calculated with the Kaplan-Meier method.

RESULTS

The median age was 62 years (RIQ: 55-71) and the mean tumour size was 34.8 (10-77) mm. Histopathological results were: 6 (40%) clear cell RCC, 4 (26.7%) papillary, 3 (20%) chromophobe and 2 (13.3%) oncocytic. The pathologic stages were: 11 (73.3%) pT1a, 1 (6.7%) pT1b and 3 (20%) pT3a. The median follow-up was 84 months (IQR 72-120). 2 patients had metastatic recurrence and this was the cause of death. The first one had recurrence at 112 months and the second one at 59. 5-year CSS and RFS were 87.5% and 93.3% respectively.

CONCLUSIONS

In our experience, patients with PSM after PN can be managed conservatively with satisfactory long-term oncological outcomes.

Classification of positive surgical margins and tumor recurrence after nephron-sparing surgery for small renal masses

BACKGROUND

The association of positive margin and local recurrence after nephron-sparing surgery (NSS) remains a notably controversial issue. The aim of the present study was to investigate the relationship between classification of positive surgical margins (PSMs) and tumor recurrence based pathological findings.

METHODS

Clinical, pathological, and follow-up data of 600 small renal cancer patients who underwent NSS between November 2007 and November 2017 at four hospitals in China were analyzed retrospectively.

RESULTS

Of the 600 reviewed patients, 20 had positive margins. During the follow-up period of 56 months, only three cases of tumor recurrence were identified. Pathological examination was performed, and subsequently a new classification criteria were proposed: 1) False PSMs, which could be further divided into three subtypes: i) no standard processing performed on pathological specimens (seven patients); ii) incidental incision into the tumor during operation, with the tumor bed free of tumor residues (four patients); iii) part of the tumor pseudocapsule was noted to be remained in the tumor bed, with no signs of tumor residue (four patients). 2) True PSMs with two subtypes: i) a large number of residual tumor cells at the surgical margin (three patients); ii) incision of satellite tumor nodules detected around a large tumor (two patients).

CONCLUSION

Taken together, PSMs in NSS were rarely found. Based on the pathological examination findings, PSMs can be divided into false positive and true positive. This being said, PSMs were determined to be poor predictors for local recurrence, with no predominant association with true tumor remnants in the majority of our evaluated cases. Through the key findings of our study, we concluded that PSMs should be carefully analyzed and treated on a case-by-case basis.

Technical Considerations for Nephron-Sparing Surgery in Children: What Is Needed to Preserve Renal Units?

BACKGROUND

Chemotherapy is used preoperatively for children with bilateral Wilms tumor (BWT) or unilateral high-risk Wilms tumor (UHRWT) to promote tumor regression to facilitate renal preservation with nephron-sparing surgery (NSS). In adults, various surgical techniques have been described to preserve renal tissue. Few studies have examined the use of surgical adjuncts in NSS in children with renal tumors.

METHODS

We performed a multi-institutional retrospective review of patients with BWT or UHRWT. Patient demographics, tumor size at diagnosis, following neoadjuvant chemotherapy, utilization of surgical adjuncts including intraoperative ultrasound (IOUS), margin status, complications, renal function, and follow-up were recorded.

RESULTS

The cohort comprised 23 patients: 18 BWT, 3 UHRWT, and 2 patients with solitary kidney. Twenty-two of the 23 patients had successful NSS. IOUS was used 19 times, and seven had positive margins after surgery. Cooling/vascular isolation was used six times. At a median follow-up of 18 mo, median estimated glomerular filtration rate Schwartz was 126 mL/min/1.73 m² and median serum creatinine 0.39 mg/dL in the 22 patients who had successful NSS. There have been no tumor recurrences.

CONCLUSIONS

In patients with BWT and UHRWT, surgical adjuncts such as cooling/vascular isolation are uncommonly performed. IOUS may be helpful but does not guarantee negative microscopic margins.

LEVEL OF EVIDENCE

Level 4, Case series with no comparison group.

Robust augmented reality registration method for localization of solid organs' tumors using CT-derived virtual biomechanical model and fluorescent fiducials

BACKGROUND

Augmented reality (AR) is the fusion of computer-generated and real-time images. AR can be used in surgery as a navigation tool, by creating a patient-specific virtual model through 3D software manipulation of DICOM imaging (e.g., CT scan). The virtual model can be superimposed to real-time images enabling transparency visualization of internal anatomy and accurate localization of tumors. However, the 3D model is rigid and does not take into account inner structures' deformations. We present a concept of automated AR registration, while the organs undergo deformation during surgical manipulation, based on finite element modeling (FEM) coupled with optical imaging of fluorescent surface fiducials.

METHODS

Two 10 × 1 mm wires (pseudo-tumors) and six 10 × 0.9 mm fluorescent fiducials were placed in ex vivo porcine kidneys (n = 10). Biomechanical FEM-based models were generated from CT scan. Kidneys were deformed and the shape changes were identified by tracking the fiducials, using a near-infrared optical system. The changes were registered automatically with the virtual model, which was deformed accordingly. Accuracy of prediction of pseudo-tumors' location was evaluated with a CT scan in the deformed status (ground truth). In vivo: fluorescent fiducials were inserted under ultrasound guidance in the kidney of one pig, followed by a CT scan. The FEM-based virtual model was superimposed on laparoscopic images by automatic registration of the fiducials.

RESULTS

Biomechanical models were successfully generated and accurately superimposed on optical images. The mean measured distance between the estimated tumor by biomechanical propagation and the scanned tumor (ground truth) was 0.84 ± 0.42 mm. All fiducials were successfully placed in in vivo kidney and well visualized in near-infrared mode enabling accurate automatic registration of the virtual model on the laparoscopic images.

CONCLUSIONS

Our preliminary experiments showed the potential of a biomechanical model with fluorescent fiducials to propagate the deformation of solid organs' surface to their inner structures including tumors with good accuracy and automatized robust tracking.

Ambient ionization mass spectrometric analysis of human surgical specimens to distinguish renal cell carcinoma from healthy renal tissue

Touch spray-mass spectrometry (TS-MS) is an ambient ionization technique (ionization of unprocessed samples in the open air) that may find intraoperative applications in quickly identifying the disease state of cancerous tissues and in defining surgical margins. In this study, TS-MS was performed on fresh kidney tissue (∼1-5 cm(3)), within 1 h of resection, from 21 human subjects afflicted by renal cell carcinoma (RCC). The preliminary diagnostic value of TS-MS data taken from freshly resected tissue was evaluated. Principal component analysis (PCA) of the negative ion mode (m/z 700-1000) data provided the separation between RCC (16 samples) and healthy renal tissue (13 samples). Linear discriminant analysis (LDA) on the PCA-compressed data estimated sensitivity (true positive rate) and specificity (true negative rate) of 98 and 95 %, respectively, based on histopathological evaluation. The results indicate that TS-MS might provide rapid diagnostic information in spite of the complexity of unprocessed kidney tissue and the presence of interferences such as urine and blood. Desorption electrospray ionization-MS imaging (DESI-MSI) in the negative ionization mode was performed on the tissue specimens after TS-MS analysis as a reference method. The DESI imaging experiments provided phospholipid profiles (m/z 700-1000) that also separated RCC and healthy tissue in the PCA space, with PCA-LDA sensitivity and specificity of 100 and 89 %, respectively. The TS and DESI loading plots indicated that different ions contributed most to the separation of RCC from healthy renal tissue (m/z 794 [PC 34:1 + Cl](-) and 844 [PC 38:4 + Cl](-) for TS vs. m/z 788 [PS 36:1 - H](-) and 810 [PS 38:4 - H](-) for DESI), while m/z 885 ([PI 38:4 - H](-)) was important in both TS and DESI. The prospect, remaining hurdles, and future work required for translating TS-MS into a method of intraoperative tissue diagnosis are discussed. Graphical abstract Touch spray-mass spectrometry used for lipid profiling of fresh human renal cell carcinoma. Left) Photograph of the touch spray probe pointed at the MS inlet. Right) Average mass spectra of healthy renal tissue (blue) and RCC (red).

Nephron-sparing surgery in renal cell carcinoma: current perspectives on technical issues

Surgical resection remains the standard treatment for renal cell carcinoma. Although historically the concept of wide excision of the affected kidney dictated surgical thinking for more than half a century, a better understanding of the biology of this tumor, standardized staging, and changing patterns of presentation permit today a refined management approach with nephron-sparing surgery, thus limiting potential long-term morbidity by maximizing the preservation of functional renal parenchyma. This paper aims to review the current status of nephron-sparing surgery for solid renal masses with an emphasis on indications, preoperative assessment, and operative technical issues, summarizing the most recent existing data on the subject.

Intraoperative ultrasound control of surgical margins during partial nephrectomy

Aims:

To evaluate a simple and fast technique to ensure negative surgical margins on partial nephrectomies, while correlating margin statuses with the final pathology report.

Subjects and Methods:

This study was conducted for patients undergoing partial nephrectomy (PN) with T1–T2 renal tumors from January 2010 to the end of December 2015. Before tumor removal, intraoperative ultrasound (US) localization was performed. After tumor removal and before performing hemostasis of the kidney, the specimens were placed in a saline solution and a US was performed to evaluate if the tumor's capsule were intact, and then compared to the final pathology results.

Results:

In 177 PN(s) (147 open procedures and 30 laparoscopic procedures) were performed on 147 patients. Arterial clamping was done for 32 patients and the mean warm ischemia time was 19 ± 6 min. The mean US examination time was 41 ± 7 s. The US analysis of surgical margins was negative in 172 cases, positive in four, and in only one case it was not possible to conclude. The final pathology results revealed one false positive surgical margin and one false negative surgical margin, while all other margins were in concert with US results. The mean tumor size was 3.53 ± 1.43 cm, and the mean surgical margin was 2.8 ± 1.5 mm.

Conclusions:

The intraoperative US control of resection margins in PN is a simple, efficient, and effective method for ensuring negative surgical margins with a small increase in warm ischemia time and can be conducted by the operating urologist.

Rapid evaluation of fresh ex vivo kidney tissue with full-field optical coherence tomography

BACKGROUND

Full-field optical coherence tomography (FFOCT) is a real-time imaging technique that rapidly generates images reminiscent of histology without any tissue processing, warranting its exploration for evaluation of ex vivo kidney tissue.

METHODS

Fresh tissue sections from tumor and adjacent nonneoplastic kidney (n = 25 nephrectomy specimens; clear cell renal cell carcinoma (CCRCC) = 12, papillary RCC (PRCC) = 4, chromophobe RCC (ChRCC) = 4, papillary urothelial carcinoma (PUC) = 1, angiomyolipoma (AML) = 2 and cystic nephroma = 2) were imaged with a commercial FFOCT device. Sections were submitted for routine histopathological diagnosis.

RESULTS

Glomeruli, tubules, interstitium, and blood vessels were identified in nonneoplastic tissue. In tumor sections, the normal architecture was completely replaced by either sheets of cells/trabeculae or papillary structures. The former pattern was seen predominantly in CCRCC/ChRCC and the latter in PRCC/PUC (as confirmed on H&E). Although the cellular details were not very prominent at this resolution, we could identify unique cytoplasmic signatures in some kidney tumors. For example, the hyper-intense punctate signal in the cytoplasm of CRCC represents glycogen/lipid, large cells with abundant hyper-intense cytoplasm representing histiocytes in PRCC, and signal-void large polygonal cell representing adipocytes in AML. According to a blinded analysis was performed by an uropathologist, all nonneoplastic tissues were differentiated from neoplastic tissues. Further, all benign tumors were called benign and malignant were called malignant. A diagnostic accuracy of 80% was obtained in subtyping the tumors.

CONCLUSION

The ability of FFOCT to reliably differentiate nonneoplastic from neoplastic tissue and identify some tumor types makes it a valuable tool for rapid evaluation of ex vivo kidney tissue e.g. for intraoperative margin assessment and kidney biopsy adequacy. Recently, higher resolution images were achieved using an experimental FFOCT setup. This setup has the potential to further increase the diagnostic accuracy of FFOCT.

Intraoperative and surgical specimen (ex vivo) ultrasound in the assessment of margins at partial nephrectomy

PURPOSE

To correlate the accuracy of intraoperative and surgical specimen (ex vivo) ultrasound (US) with pathological margin status at partial nephrectomy.

MATERIALS AND METHODS

Patients undergoing partial nephrectomy for T1 renal tumours in the period May 2010-January 2014 at a single institution who had intraoperative specimen US were included. PN was performed by standardised technique with intraoperative tumour localisation. Following excision, surgical specimen (ex vivo) US was performed and the margin status was compared to the final histopathological analysis. The specificity of US to identify margin status was calculated as was the correlation between the ultrasonographic and final pathological margin.

RESULTS

Forty-five patients were included (median age 61 years). Mean tumour size was 28.1 ± 10 mm, and 89 % were renal cell carcinomas with the remainder being oncocytomas. Forty-four cases had negative surgical margins on pathological analysis, and US had a specificity of 100 %. There was a strong correlation between the margin as measured on US and final analysis (Pearson's r = 0.86, p < 0.001).

CONCLUSION

Results show that intraoperative, surgical specimen (ex vivo) US control of resection margins in patients undergoing PN is feasible and efficient. It represents a promising tool to ensure margin negativity during PN.

Increasing volume of non-neoplastic parenchyma in partial nephrectomy specimens is associated with chronic kidney disease upstaging

INTRODUCTION

We examined the effect of non-neoplastic parenchymal volumes (NNPVs) in partial nephrectomy (PN) surgical specimens on long-term postoperative renal function. PN for renal cortical neoplasms has demonstrated superior long-term renal function outcomes compared with radical nephrectomy. Minimizing the distance between the surgical margin and tumor will reduce the NNPV removed. The role of NNPV on postoperative outcomes has been preliminarily investigated, with varying results. Thus, we sought to determine the association between the NNPV removed and postoperative chronic kidney disease (CKD) staging.

MATERIALS AND METHODS

Our institutional database was queried for patients who had undergone PN from 1990 to 2012. The demographic and pathologic data were collected. The ellipsoid formula was used to calculate the surgical specimen and tumor volumes, which were then subtracted from each other to determine the NNPV. The estimated glomerular filtration rate (eGFR) was calculated using the Modification of Diet in Renal Disease formula. Binary logistic regression analysis was used to determine the predictors of postoperative CKD upstaging according to the eGFR.

RESULTS

A total of 584 patients meeting the inclusion criteria had undergone PN. On binary logistic regression analysis, controlling for age, tumor volume, surgical modality, and preoperative CKD stage, an increasing NNPV in the surgical specimen was independently associated with postoperative CKD upstaging (odds ratio, 1.004; P = .007).

CONCLUSION

An increasing NNPV removed during PN correlated with CKD upstaging using the eGFR; therefore, additional emphasis should be placed on healthy parenchymal preservation, with long-term follow-up to ensure adequate oncologic outcomes.

Intraoperative sonography during open partial nephrectomy for renal cell cancer: does it alter surgical management?

OBJECTIVE

The purpose of this study is to evaluate whether intraoperative ultrasound (IOUS) during open partial nephrectomy alters the surgical management for renal cell cancer (RCC).

MATERIALS AND METHODS

One hundred ninety-eight consecutive patients undergoing IOUS during open partial nephrectomy for RCC were selected for retrospective review of clinical and imaging data. Patient age and sex, the local extent of the primary lesion, and the presence of additional lesions were recorded. Ultrasound findings were compared with preoperative CT or MRI to determine whether the IOUS findings changed surgical management. Summary statistics were performed to assess what percentage of patients with additional IOUS findings had a change in their surgical management. The Kaplan-Meier method was used to estimate 5-year overall survival (OS) and event-free survival (EFS) rates for all patients. Patients were followed for 9-12 years to assess survival and measure recurrence rates.

RESULTS

Twenty-one of 198 patients (10.6%; 95% CI, 6.7-15.8%) had additional findings on IOUS not seen on preoperative imaging. As a result, surgery was modified in 15 of these 21 patients (71.4%; 95% CI, 47.8-88.7%). The 5-year OS rate was 81%, and the EFS rate was 76% for the whole group; most deaths were due to unrelated causes. There was no statistically significant difference in OS (p = 0.867) and EFS (p = 0.069) rates among patients who had a change of management because of additional lesions seen by IOUS.

CONCLUSION

IOUS performed during open partial nephrectomy for resection of RCC shows additional findings compared with preoperative cross-sectional imaging that may alter surgical management.

Clinical impact of targeted therapies in patients with metastatic clear-cell renal cell carcinoma

Introduction

The aim of this retrospective clinical study was to assess, in the context of the recent evolution of systemic therapies, the potential effect of targeted therapies on overall survival (OS) of patients with metastatic clear-cell renal cell carcinoma (mccRCC) in daily practice.

Patients and methods

All consecutive patients with histologically confirmed mccRCC who received systemic therapy between January 2000 and December 2010 in two oncology treatment centers in our Franche-Comté region in eastern France were included in the analysis. The primary end point was OS. The analysis of prognostic factors was performed using a two-step approach: univariate then multivariate analysis with a stepwise Cox proportional hazards regression model.

Results

For the entire cohort of 111 patients, the median OS was 17 months (95% confidence interval [CI]; 13–22 months) and the two-year OS was 39%. Three prognostic factors were independent predictors of long survival: prior nephrectomy (hazard ratio =0.38 [0.22–0.64], P<0.0001); systemic therapy by targeted therapy (hazard ratio =0.50 [0.31–0.80], P=0.005); and lack of liver metastasis (hazard ratio =0.43 [0.22–0.82], P=0.002). Median OS was 21 months [14–29 months] for patients who received at least one targeted therapy compared with 12 months [7–15 months] for patients who were treated only by immunotherapy agents (P=0.003).

Conclusion

Our results suggest that targeted therapies are associated with improved OS in comparison with cytokines, which is in line with other publications.

Augmented reality partial nephrectomy: examining the current status and future perspectives

A minimal access approach to partial nephrectomy has historically been under-utilized, but is now becoming more popular with the growth of robot-assisted laparoscopy. One of the criticisms of minimal access partial nephrectomy is the loss of haptic feedback. Augmented reality operating environments are forecast to play a major enabling role in the future of minimal access partial nephrectomy by integrating enhanced visual information to supplement this loss of haptic sensation. In this article, we systematically examine the current status of augmented reality in partial nephrectomy by identifying existing research challenges and exploring future agendas for this technology to achieve wider clinical translation.

Nephron-sparing surgery for adenocarcinoma in a renal allograft

The incidence of malignant tumors in recipients of renal allografts is higher than in the general population. Renal cell carcinoma (RCC) accounts for 4.6% of the tumors in transplanted patients; of them, only 10% are found in transplanted kidneys. Transplantectomy has always been the usual treatment. However, during the last years, nephron-sparing surgery of the allograft is more frequently done in well-selected cases, and therefore dialysis can be avoided. We report the case of a 37-year-old female patient with renal transplant, diagnosed with a 4.5 cm tumor in the lower pole of the renal allograft. The patient underwent partial nephrectomy successfully. Six years after surgery, there is no evidence of recurrence of the disease and the patient maintains an adequate renal function.

Incomplete thermal ablation stimulates proliferation of residual renal carcinoma cells in a translational murine model

What's known on the subject? and What does the study add? Thermal ablation influences the local tissue microenvironment. Several studies have reported that residual tumour cells may exhibit a more aggressive phenotype. This study shows that incomplete CA and RFA cause an increased proliferation and decreased apptosis of residual renal tumour cells. This may be caused by stimulatory factors such as hypoxia, HSPs and inflammatory cells.

OBJECTIVE

To compare the effect of incomplete thermal ablation vs partial nephrectomy (PN) on growth stimulation and cellular survival in renal tumours.

MATERIALS AND METHODS

Renca renal tumours were transplanted under the renal capsule of mice (four to six mice/group) after which incomplete radiofrequency ablation (RFA), cryoablation (CA) or PN was performed. At several time points after treatment, presence of cell proliferation, apoptosis, hypoxic areas, inflammatory factors and the heat-shock proteins (HSPs) 70 and 90 were evaluated using immunohistochemistry.

RESULTS

At 2 h after thermal ablation residual tumour cells showed increased proliferation. This hyperproliferation was significantly stronger after RFA than CA (P < 0.05) and not present after PN. Residual cells showed increased apoptosis after 2 h and decreased apoptosis from 2 days after thermal ablation. Apoptotic cells were significantly less evident at 3 days after RFA (P < 0.001). Hypoxic areas and HSPs were increasingly present from 2 h up to 7 days after thermal ablation (P < 0.001). Inflammatory cells infiltrated mainly the necrotic areas after thermal ablation, and their abundance peaked at 1 week after ablation (P < 0.05). The increased cell growth was preceded by hypoxia and presence of HSPs.

CONCLUSIONS

CA and RFA result in an increased proliferation and decreased apoptosis of residual renal tumour cells. This hyperproliferation may be caused by stimulatory factors, e.g. hypoxia, HSPs and inflammatory cells, and could facilitate recurrences of renal tumours after thermal ablation. This study highlights the importance of achieving complete tumour destruction.

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.

Ex vivo ultrasound control of resection margins during partial nephrectomy

PURPOSE

Surgery remains the treatment of choice for localized renal neoplasms. While radical nephrectomy was long considered the gold standard, partial nephrectomy has equivalent oncological results for small tumors. The role of negative surgical margins continues to be debated. Intraoperative frozen section analysis is expensive and time-consuming. We assessed the feasibility of intraoperative ex vivo ultrasound of resection margins in patients undergoing partial nephrectomy and its correlation with margin status on definitive pathological evaluation.

MATERIALS AND METHODS

A study was done at 2 institutions from February 2008 to March 2011. Patients undergoing partial nephrectomy for T1-T2 renal tumors were included in analysis. Partial nephrectomy was done by a standardized minimal healthy tissue margin technique. After resection the specimen was kept in saline and tumor margin status was immediately determined by ex vivo ultrasound. Sequential images were obtained to evaluate the whole tumor pseudocapsule. Results were compared with margin status on definitive pathological evaluation.

RESULTS

A total of 19 men and 14 women with a mean ± SD age of 62 ± 11 years were included in analysis. Intraoperative ex vivo ultrasound revealed negative surgical margins in 30 cases and positive margins in 2 while it could not be done in 1. Final pathological results revealed negative margins in all except 1 case. Ultrasound sensitivity and specificity were 100% and 97%, respectively. Median ultrasound duration was 1 minute. Mean tumor and margin size was 3.6 ± 2.2 cm and 1.5 ± 0.7 mm, respectively.

CONCLUSIONS

Intraoperative ex vivo ultrasound of resection margins in patients undergoing partial nephrectomy is feasible and efficient. Large sample studies are needed to confirm its promising accuracy to determine margin status.

Cryoablation for endophytic renal cell carcinoma: intermediate-term oncologic efficacy and safety

Purpose

To evaluate the efficacy and safety of laparoscopic renal cryoablation (LRC) of small endophytic renal cell carcinoma, for which surgical treatment is technically difficult.

Materials and Methods

We enrolled patients with endophytic tumors from a prospectively collected database of 45 renal tumors in 39 patients who had undergone LRC from June 2005 to May 2009. An endophytic tumor was defined as less than 40% of the lesion extending off the surface of the kidney. We evaluated surgical and oncological outcomes.

Results

Among the treated tumors, 17 tumors (37.8%) were defined as endophytic tumors and 15 tumors from 14 patients were confirmed as renal cell carcinoma (RCC) in the pathologic examination of the tissue biopsy that was conducted at the time of LRC. The mean American Society of Anesthesiologists (ASA) score of the whole patient group was 2.9 (range, 1-4), and 85.7% (12/14) of the patients had an ASA physical status score over 3. The mean tumor size was 2.8 cm (range, 1.7-3.7 cm). The layout of the cryoprobe was carefully planned preoperatively on the basis of radiologic evaluation in all tumors. Multiple cryoprobes (mean, 3.2; range, 2-5) were used. No major complications, including open surgical conversion and nephrectomy due to bleeding, occurred. No patient experienced clinical symptoms of collecting system injuries. During the mean follow-up of 32.6 months (range, 12-51 months), radiologic evidence of tumor recurrence was found in one patient (6.7% for RCC). With the exception of this patient, all other patients have remained free of recurrence or metastasis, as determined by periodic radiologic workups.

Conclusions

In this series of patients with intermediate-term follow-up, LRC for endophytic renal cell carcinoma showed acceptable oncological and surgical outcomes without sequelae in the collecting system.

Efficacy and safety of nephron-sparing surgery

To analyse the current evidence of efficacy and safety of nephron-sparing surgery (NSS) that encompasses open partial nephrectomy (OPN), laparoscopic partial nephrectomy (LPN) and robotic partial nephrectomy in the management of localized renal cell carcinoma (RCC). Oncological data, complications and postoperative renal function were reviewed for the most important series of partial nephrectomy. Partial nephrectomy (PN) provides similar oncological control as radical nephrectomy (RN) and is superior to RN with respect to preserving renal function and preventing chronic kidney disease. OPN remains the first treatment option for T1 renal tumors in centers without advanced laparoscopic expertise. Indications for LPN have expanded as such that LPN is suited for most renal tumors provided that the procedure is carried out in selected patients by an experienced laparoscopic surgeon. Warm ischemia time should be kept within 20 min, which is currently recommended regardless of surgical approach. In experienced hands, LPN yields intermediate oncological efficacy and renal function outcome comparable to open surgery in the treatment of pT1 renal tumors. Positive surgical margin rates are comparable after LPN and OPN. In contemporary series, the morbidity of LPN is decreasing to become similar to that of OPN. Preliminary results with robotic PN are comparable to results obtained with LPN. Additional studies are required to validate these results and compare with other current methods, such as thermal ablation. NSS is effective and safe for the management of localized RCC and is the gold standard to which new ablative techniques need to be compared.

Efficacy of parenchymal compression in open partial nephrectomies: a comparison with conventional vascular clamping

Purpose

We evaluated the efficacy of parenchymal compression in open partial nephrectomies (OPNs) compared with that of the conventional vascular clamping method.

Materials and Methods

OPNs were conducted by means of the parenchymal compression technique at our institution from April 2006. Among these, the operative outcomes of 20 consecutive patients with normal preoperative renal function (Group 1) were matched with those of 20 control patients from the database of previous operations who underwent OPN with a conventional vascular clamping method (Group 2).

Results

All preoperative characteristics were similar in both groups. The operative time was significantly higher for Group 2 (132.4±17.7 vs. 151.4±21.4 minutes, p=0.031). Estimated blood loss was slightly higher for Group 2, with marginal statistical significance (173.7±11.5 vs. 211.2±43.8 ml, p=0.06). Histologic examination revealed that over 80% of the tumors in both groups were renal cell carcinomas. For all patients, the pathology results of specimens were negative. Serum creatinine, checked at 1, 3, and 7 days after the operation, was significantly increased in both groups to a similar degree. However, 30 days after surgery, the patterns of serial serum creatinine levels demonstrated statistically significant differences by repeated-measures ANOVA (p<0.001), with a trend of more elevated in Group 2 than in Group 1, although values were within the normal range. No major complications occurred in either group.

Conclusions

OPN using the parenchymal compression method had acceptable outcomes in terms of complete tumor control, avoiding warm ischemic time, and minimizing blooding, with good preservation of renal function and minimal complications.

Laparoscopic Partial Nephrectomy Using FloSeal for Hemostasis: Technique and Experiences in 102 Patients

Objectives. The authors report their techniques, perioperative data, and oncological outcome for laparoscopic partial nephrectomy in a single-center experience with 3 different surgeons. Patients and methods. A total of 102 consecutive patients underwent laparoscopic transperitoneal partial nephrectomy for exophytic tumors using FloSeal for hemostasis. Mean age was 58 years (range = 26-79 years), and median tumor size was 2.6 cm (range = 0.5-8.5 cm). In 84 cases, the renal artery was clamped using endoscopic bulldog clamps, and tumor resection was performed using scissors or the harmonic scalpel. Hemostasis was achieved by application of FloSeal; lesions of the collecting system were closed with Lahodny sutures in 33 cases (31%). Frozen sections were obtained for margin status. Results . All 102 procedures were successful with no intraoperative complications. Mean surgical time was 201 minutes (range = 60-355 minutes); clamping time was 25.8 minutes (range = 6-75 minutes) in 64 cases. Margins were negative in 92 cases; in 8 cases secondary resection was necessary to achieve negative margin status, and in 2 cases radical nephrectomy was performed. Histological findings were clear-cell carcinoma in 51 (50.0%), papillary carcinoma in 26 (25.5%), and others in 25 (24.5%) cases. At a mean follow-up of 32 months (12-62 months), no recurrence was observed. Conclusions. Laparoscopic partial nephrectomy with the use of FloSeal is a feasible and safe method for treatment of small renal masses. The technique is reproducible by surgeons who are used to complex laparoscopic procedures. Patient outcome during follow-up was comparable with data published for open standard procedures.

Robot assisted partial nephrectomy versus laparoscopic partial nephrectomy for renal tumors: a multi-institutional analysis of perioperative outcomes

PURPOSE

Robot assisted partial nephrectomy is rapidly emerging as an alternative to laparoscopic partial nephrectomy for the treatment of renal malignancy. We present the largest multi-institution comparison of the 2 approaches to date, describing outcomes from 3 experienced minimally invasive surgeons.

MATERIALS AND METHODS

We performed a retrospective chart review, evaluating 118 consecutive laparoscopic partial nephrectomies and 129 consecutive robot assisted partial nephrectomies performed between 2004 and 2008 by 3 experienced minimally invasive surgeons at 3 academic centers. Perioperative data were recorded along with clinical and pathological outcomes.

RESULTS

The robot assisted and laparoscopic partial nephrectomy groups were equivalent in terms of age, gender, body mass index, American Society of Anesthesiologists classification (2.3 vs 2.4) and radiographic tumor size (2.9 vs 2.6 cm), respectively. Comparison of operative data revealed no significant differences in terms of overall operative time (189 vs 174 minutes), collecting system entry (47% vs 54%), pathological tumor size (2.8 vs 2.5 cm) and positive margin rate (3.9% vs 1%) for robot assisted and laparoscopic partial nephrectomy, respectively. Intraoperative blood loss was less for robot assisted vs laparoscopic partial nephrectomy (155 vs 196 ml, p = 0.03) as was length of hospital stay (2.4 vs 2.7 days, p <0.0001). Warm ischemia times were significantly shorter in the robot assisted partial nephrectomy series (19.7 vs 28.4 minutes, p <0.0001). Subset analysis based on complexity revealed that tumor complexity had no effect on operative time or estimated blood loss for robot assisted partial nephrectomy, although complexity did affect these factors for laparoscopic partial nephrectomy. In addition, for simple and complex tumors robot assisted partial nephrectomy provided significantly shorter warm ischemic time than laparoscopic partial nephrectomy (15.3 vs 25.2 minutes for simple, p <0.0001; 25.9 vs 36.7 minutes for complex, p = 0.0002). There were no intraoperative complications during robot assisted partial nephrectomy vs 1 complication during laparoscopic partial nephrectomy. Postoperative complication rates were similar for robot assisted and laparoscopic partial nephrectomy (8.6% vs 10.2%).

CONCLUSIONS

Robot assisted partial nephrectomy is a safe and viable alternative to laparoscopic partial nephrectomy, providing equivalent early oncological outcomes and comparable morbidity to a traditional laparoscopic approach. Moreover robot assisted partial nephrectomy appears to offer the advantages of decreased hospital stay as well as significantly less intraoperative blood loss and shorter warm ischemia time, the latter of which may help to provide maximal preservation of renal reserve. In addition, operative parameters for robot assisted partial nephrectomy appear to be less affected by tumor complexity compared to laparoscopic partial nephrectomy. Interestingly while the advantages of robotic surgery have historically been believed to aid laparoscopic naïve surgeons, these data indicate that robot assisted partial nephrectomy may also benefit experienced laparoscopic surgeons.

The contemporary role of surgery in kidney cancer

The diagnosis and treatment of renal cell carcinoma (RCC) has been the subject of major changes since the late 1980s. Initially, surgery was the only treatment available, but more recently, systemic therapies have been developed, and their introduction has modified some of the surgical indications for rcc. In addition, refinements in surgical technique and the introduction of minimally invasive approaches have revolutionized patient care and bear the promise of even more improvements to come. This paper provides an up-to-date overview of recent developments in the surgical treatment of RCC.

Augmented reality: a new tool to improve surgical accuracy during laparoscopic partial nephrectomy? Preliminary in vitro and in vivo results

BACKGROUND

Use of an augmented reality (AR)-based soft tissue navigation system in urologic laparoscopic surgery is an evolving technique.

OBJECTIVE

To evaluate a novel soft tissue navigation system developed to enhance the surgeon's perception and to provide decision-making guidance directly before initiation of kidney resection for laparoscopic partial nephrectomy (LPN).

DESIGN, SETTING, AND PARTICIPANTS

Custom-designed navigation aids, a mobile C-arm capable of cone-beam imaging, and a standard personal computer were used. The feasibility and reproducibility of inside-out tracking principles were evaluated in a porcine model with an artificially created intraparenchymal tumor in vitro. The same algorithm was then incorporated into clinical practice during LPN.

INTERVENTIONS

Evaluation of a fully automated inside-out tracking system was repeated in exactly the same way for 10 different porcine renal units. Additionally, 10 patients underwent retroperitoneal LPNs under manual AR guidance by one surgeon.

MEASUREMENTS

The navigation errors and image-acquisition times were determined in vitro. The mean operative time, time to locate the tumor, and positive surgical margin were assessed in vivo.

RESULTS AND LIMITATIONS

The system was able to navigate and superpose the virtually created images and real-time images with an error margin of only 0.5 mm, and fully automated initial image acquisition took 40 ms. The mean operative time was 165 min (range: 135-195 min), and mean time to locate the tumor was 20 min (range: 13-27 min). None of the cases required conversion to open surgery. Definitive histology revealed tumor-free margins in all 10 cases.

CONCLUSIONS

This novel AR tracking system proved to be functional with a reasonable margin of error and image-to-image registration time. Mounting the pre- or intraoperative imaging properties on real-time videoendoscopic images in a real-time manner will simplify and increase the precision of laparoscopic procedures.

Towards image guided robotic surgery: multi-arm tracking through hybrid localization

OBJECTIVE

Use of the robotic assisted surgery has been increasing in recent years, due both the continuous increase in the number of applications and the clinical benefits that surgical robots can provide. Currently robotic assisted surgery relies on endoscopic video for navigation, providing only surface visualization, thus limiting subsurface vision. To be able to visualize and identify subsurface information, techniques in image-guidance can be used. As part of designing an image guidance system, all arms of the robot need to be co-localized in a common coordinate system.

METHODS

In order to track multiple arms in a common coordinate space, intrinsic and extrinsic tracking methods can be used. First, the intrinsic tracking of the daVinci, specifically of the setup joints is analyzed. Because of the inadequacy of the setup joints for co-localization a hybrid tracking method is designed and implemented to mitigate the inaccuracy of the setup joints. Different both optical and magnetic tracking methods are examined for setup joint localization.

RESULTS

The hybrid localization method improved the localization accuracy of the setup joints. The inter-arm accuracy in hybrid localization was improved to 3.02 mm. This inter-arm error value was shown to be further reduced when the arms are co-registered, thus reducing common error.