[Diagnosis of upper urinary tract tumors. A pending challenge]

Early diagnosis of upper urinary tract tumors is not easy. The development of endoscopic equipment has expanded the group of patients candidates for minimally invasive treatment. Only by providing accurate tumor staging and grading can clinicians decide which patients should be offered conservative therapies. We need diagnostic methods that allow us to make an early and accurate diagnosis for these lesions, as well as safe follow-up. Our proposal is to present a review of the most used diagnostic method, their features, and future diagnostic tools. The diagnostic arsenal requires further improvement. Only through accurate diagnosis, we will be able to safely provide conservative treatment. Developing new diagnostic techniques seem to move us closer to this goal even more. We propose a working algorithm on the management of these lesions.

Current patterns of presentation and treatment of renal masses: a clinical research office of the endourological society prospective study

PURPOSE

To assess epidemiologic characteristics, clinical and pathologic patterns of presentation, and treatment strategies in a contemporary population with renal masses (RMs).

METHODS

The Clinical Research Office of the Endourological Society collected prospective epidemiologic, clinical, and pathologic data on consecutive patients with RMs who were treated during a 1-year period in 98 centers worldwide. Preoperative assessment and treatment were performed according to local clinical practice guidelines.

RESULTS

From January 2010 to February 2012, 4288 patients (4355 cases, 4815 tumors) were treated for a RM. The mean age of the cohort was 61.5 years, and the ratio male:female 1.8:1. Caucasians represented 75% of the population, and the median body mass index was 27. The cohort exhibited a high rate of comorbidity (65.6%), including a 48.5% rate of hypertension; one-third of patients had a combination of two or more comorbidities. One-third of patients (36%) had risk factors for renal-cell carcinoma (RCC), of which smoking and obesity were the most common. Diagnosis was incidental in 67% of cases, and 22.2% of cases had chronic kidney disease stage ≥III at presentation. Median radiologic size was 44 mm (range 2-300 mm) and 68% were cT1. Radical nephrectomy and nephron-sparing surgery (NSS) including ablation were performed in 52% and 46% of cases, respectively, while 3.6% of cases were actively surveyed. Median pathologic size was 43 mm (range 2-300 mm) and 63% of the RCCs were pT1.

CONCLUSIONS

Current patterns of presentation of RMs are consistent with the decreasing trends in age and clinical or pathologic size and increasing incidental diagnosis. Patients exhibit a considerable basal comorbidity and presence of risk factors for RCC. Half of the cases are treated by a nephron-sparing modality with an increase in the penetration of NSS techniques in the contemporary urologic practice.

Evaluation of renal masses with contrast-enhanced ultrasound

The clinical need for characterising small renal masses (SRMs) is increasing due to their rising incidental detection. This increase is especially seen in younger and older generations and concerns mainly SRMs. Diagnostics is mainly made by contrast-enhanced CT or MRI. However, these imaging methods fail to accurately distinguishing benign from malignant SRMs. Other disadvantages of CT or MRI are high costs, the use of ionizing radiation, nephrotoxicity induced by iodine contrast agents or nephrogenic systemic fibrosis (NSF) induced by gadolinium contrast agents. Contrast-enhanced ultrasound (CEUS) is based on ultrasonography and microbubbles to real-time visualize the renal blood flow without the use of nephrotoxic agents or ionizing radiation. This comprehensive review evaluates the capabilities of CEUS in the diagnostics of benign (angiomyolipomas, cysts, oncocytomas, pseudotumors) and malignant masses (renal cell carcinomas), and focuses on possible future treatment.

Prognostic models and factors for patients with renal-cell carcinoma: a survey on their use among urologists

PURPOSE

To assess the use of prognostic factors and models in renal-cell carcinoma (RCC) and to gain insight in the motivations precluding prognosis estimation and the use of prognosticators.

MATERIALS AND METHODS

A questionnaire was sent to 110 urologists involved in the Clinical Research Office of the Endourological Society (CROES) Global Renal Mass Study. Frequencies were gathered using descriptive statistics.

RESULTS

The majority of the 86 responders worked in a university hospital in Europe. Most of the urologists (97.7%) used the tumor-node-metastasis (TNM) classification, and 44% performed prognosis estimations in all patients. The main reason not to estimate prognosis was lack of accuracy (20.9%) and of additional benefit (11.6%). In addition, clinical, laboratory, or pathologic factors were used by 89.5% of the urologists and biomarkers by 16.3%. Preoperative models were used by 20.9%, postoperative models by 38.4%, and metastatic models by 38.4%. The Raj and Motzer models were the most used in preoperative and metastatic settings, while no predominance among the different postoperative models was seen. The most important reasons to skip the use of models were "lack of additional value" and "lack of familiarity" reported by 30.2% and 27.9% of the responders, respectively.

CONCLUSIONS

The TNM is the mainstay for assessing prognosis in RCC. Our data indicate that penetration of prognostic systems is, at most, moderate, suggesting limited use outside original developmental settings. On the contrary, clinical, laboratory, and pathologic factors are used by almost all urologists for prognosis estimations. The most important reason not to use models is the lack of additional value.

Contrast-enhanced ultrasound for the evaluation of the cryolesion after laparoscopic renal cryoablation: an initial report

PURPOSE

Stringent radiological follow-up is essential after renal tumor ablation. Drawbacks of postablation follow-up by contrast-enhanced computed tomography (CECT) are the associated ionizing radiation and nephrotoxic contrast agent. Contrast-enhanced ultrasound (CEUS) has shown potential to demonstrate microvasculature without using either ionizing radiation or toxic contrast agent. We assessed the concordance of enhancement patterns of CEUS and CECT/MRI in cryolesion assessment after laparoscopic renal cryoablation (LCA).

METHODS

From 01/2006 to 01/2009, a CEUS was performed before and after LCA (3 and 12 months) in addition to regular CECT/MRI. Using an enhancement score (0=no enhancement, 1=rim enhancement, 2=diffuse enhancement, 3=localized enhancement, 4=no enhancement defect), the cryolesion was assessed by both modalities, and concordance of enhancement score was assessed.

RESULTS

In total, 45 tumors were included (29 biopsy proven renal cell carcinoma (RCC), mean size 2.66 cm). One cryoablation failed, resulting in a nonenhancing cryolesion apart from the persisting renal tumor. There were no postablation recurrences during the study period. Pre-LCA: Both modalities were available in 26 cases. In 20 out of 26, there was concordance of enhancement score (77%, all cases score 3 or 4). Three months: Both modalities were available in 32 cases. Enhancement score corresponded in 23 out of 32 cases (72%). Seven cases showed enhancement on CECT/MRI ("1" in six cases, "4" in one case) with enhancement score "0"on CEUS. Two cases showed enhancement on CEUS without enhancement on CECT/MRI (specificity 92%, negative predictive value [NPV] 77%). Except one case, all enhancement resolved on subsequent imaging. Twelve months: Both modalities were available in 21 tumors. Enhancement score corresponded in 19 out of 21 cases (91%). Two cases showed enhancement on CEUS without enhancement on CECT/MRI (specificity 90%, NPV 100%).

CONCLUSION

This pilot study shows that CEUS is a safe imaging technique with high concordance of enhancement score between CEUS and CECT/MRI. While cross-sectional imaging seems sensible to demonstrate successful ablation at first follow-up, CEUS might be used to diminish the burden of contrast-enhanced cross-sectional imaging in the long-term follow-up.

Laparoscopic cryotherapy for small renal masses: Current State

OBJECTIVES

To provide an up-to-date review of the available literature on laparoscopic cryotherapy for small renal masses (SRMs) including technique description, indications and outcomes.

METHODS

A systematic literature search was conducted in March 2012, using MEDLINE and EMBASE via Ovid databases, to identify studies on laparoscopic cryotherapy for SRMs published during the last 10 years. Only English-language and human-based full manuscripts reporting case series studies with >20 participants, patient characteristics, efficacy and safety data were included.

RESULTS

No randomised controlled trials (RCTs)were identified. In total, 27 full reports addressing laparoscopic cryoablation (LCA) for SRMs were selected. The number of patients per study ranged from 20 to 144. Mean age of treated patients across the series ranged from 62 to 73 years. Mean size of renal tumors ranged from 2.7 to 4 cm, being in most cases <3 cm. The number of cryoprobes used for cryoablation ranged from 1 to 6, and only 10 series described the use of 17-gauge (1.47 mm) third-generation needles. Overall, more than 55% of all ablated lesions were pathologically confirmed RCC. Mean follow-up ranged from 9 to 93 months. Only 7 series presented a long-term follow-up of more than 36 months. Most studies were limited by a relatively short follow-up. At least four urologic groups reported intermediate- and long-term outcomes. Persistence rates ranged from 0% to 17% and recurrence rates ranged from 0% to 14%. Overall complication rates ranged from 0% to 40%.

CONCLUSIONS

Retrospective observational data and a few prospective series on LCA of SRMs show acceptable oncological 3- to 5-year outcomes with a low recurrence rate. It has proven to be a safe procedure with an overall low complication rate. It is mainly indicated for SRMs in elderly patients affected by co-morbidity and high surgical risk bearing tumours in the anterior valve of the kidney or in contact with the ureter or neighbouring organs.

Maintaining success, reducing treatment burden, focusing on survivorship: highlights from the third European consensus conference on diagnosis and treatment of germ-cell cancer

In November 2011, the Third European Consensus Conference on Diagnosis and Treatment of Germ-Cell Cancer (GCC) was held in Berlin, Germany. This third conference followed similar meetings in 2003 (Essen, Germany) and 2006 (Amsterdam, The Netherlands) [Schmoll H-J, Souchon R, Krege S et al. European consensus on diagnosis and treatment of germ-cell cancer: a report of the European Germ-Cell Cancer Consensus Group (EGCCCG). Ann Oncol 2004; 15: 1377-1399; Krege S, Beyer J, Souchon R et al. European consensus conference on diagnosis and treatment of germ-cell cancer: a report of the second meeting of the European Germ-Cell Cancer Consensus group (EGCCCG): part I. Eur Urol 2008; 53: 478-496; Krege S, Beyer J, Souchon R et al. European consensus conference on diagnosis and treatment of germ-cell cancer: a report of the second meeting of the European Germ-Cell Cancer Consensus group (EGCCCG): part II. Eur Urol 2008; 53: 497-513]. A panel of 56 of 60 invited GCC experts from all across Europe discussed all aspects on diagnosis and treatment of GCC, with a particular focus on acute and late toxic effects as well as on survivorship issues. The panel consisted of oncologists, urologic surgeons, radiooncologists, pathologists and basic scientists, who are all actively involved in care of GCC patients. Panelists were chosen based on the publication activity in recent years. Before the meeting, panelists were asked to review the literature published since 2006 in 20 major areas concerning all aspects of diagnosis, treatment and follow-up of GCC patients, and to prepare an updated version of the previous recommendations to be discussed at the conference. In addition, ∼50 E-vote questions were drafted and presented at the conference to address the most controversial areas for a poll of expert opinions. Here, we present the main recommendations and controversies of this meeting. The votes of the panelists are added as online supplements.

Differentiation between normal renal tissue and renal tumours using functional optical coherence tomography: a phase I in vivo human study

OBJECTIVE

To determine the ability of optical coherence tomography (OCT) in differentiating human renal tumours in an in-vivo setting by assessing differences in attenuation coefficient (µ(OCT); mm(-1)) as a quantitative measurement.

METHODS

Consecutive patients undergoing nephrectomy (partial/radical) or cryoablation for an enhancing solid renal tumour were included in our centre between October 2010 and May 2011. In vivo OCT images were obtained from renal tumour and normal parenchyma during surgery. Ex vivo OCT images of internal (subcapsular) tissue were obtained after longitudinal dissection of the extirpated specimen. Attenuation coefficients of the OCT images were determined off-line and compared between normal renal parenchyma and renal tumours (grouped per tissue type and per individual patient); and between OCT images recorded from tissue surface vs internal (subcapsular) tissue.

RESULTS

In vivo OCT was performed in 16 cases (11 renal cell carcinoma, three benign tumours, one non-diagnostic biopsy and one not-accessible tumour). Median attenuation coefficient of normal renal parenchyma was 5.0 mm(-1) vs 8.2 mm(-1) for tumour tissue (P < 0.001) with normal parenchyma differing significantly from malignant tumour (9.2 mm(-1), P < 0.001) and non-significantly from benign tumour (7.0 mm(-1), P = 0.050). The attenuation coefficient of benign tumours did not differ significantly from that of malignant tumours (7.0 vs 9.2 mm(-1), P = 0.139). Using patients as their own control, attenuation coefficients of normal renal parenchyma differed significantly from malignant tumour (P < 0.001) and non-significantly from benign tumour (P = 0.109). Assessed in 10 patients, there was no significant difference between attenuation coefficients of tumour surface and internal tumour (8.5 vs 9.7 mm(-1) respectively, P = 0.260).

CONCLUSIONS

In this first in vivo study on OCT for differentiation of renal tumours in humans the attenuation coefficients (as a quantitative assessment) differed significantly between normal renal parenchyma and malignant tumour. Tumour surface and internal tumour did not differ significantly, suggesting that a superficial OCT attenuation coefficient reliably assesses tissue composition inside the tumour. These results justify further research on OCT for various clinical applications in the diagnosis of renal tumours.

The penetration of renal mass biopsy in daily practice: a survey among urologists

BACKGROUND AND PURPOSE

The vast increase in recent publications on renal mass biopsy (RMB) suggests an increased interest in the subject. The objective of the survey was to assess the use of RMB in current urologic practice, including related factors such as indications and patterns in practice.

METHODS

The link to a web-based questionnaire ( www.surveymonkey.com ) was sent to all registered e-mail addresses (1854) of members of the Endourological Society in December 2010. The questionnaire contained six epidemiologic questions, 10 regarding patterns of practice, one regarding the influence of the literature, and one on future techniques. Chi-square test (for trends) was used to assess statistical significant differences among categorical answers.

RESULTS

In total, 190 responders completed the survey of whom 73% indicated performing RMB "never" or "rarely" compared with 9% performing RMB in 25% to 100% of cases. Thirteen percent of responders reported never to take a RMB. Of the latter, significantly fewer practice in university hospitals (6% vs 20%-30%, P=0.003). Main indications to perform RMB are still tumors in solitary/transplant kidneys and in metastatic disease. Lack of influence on clinical management and risk of false negatives were the main reasons not to perform biopsies. Sixty-one percent prefer histological biopsies compared with 8% who prefer cytological aspiration; 31% indicated that they combine both techniques. Other tissue differentiation techniques (Optical Coherence Tomography, Raman-spectroscopy) are unknown to 65% of urologists.

CONCLUSION

RMB is not yet applied widely in urologic practice, with academic urologists performing RMB less infrequently. Core biopsies are still preferred, although combined with cytologic punctures by a considerable number of responders.

New optical diagnostic tools in renal cell cancer

In modern medicine the profound use of abdominal imaging has led to a dramatic change of presentation of renal tumors. Smaller tumors and therefore more benign masses are being discovered, and as systemic use of renal mass biopsies is not recommended by the general guidelines, an appropriate tool to assess the biology of renal tumors is highly desirable. Apart from new developments of currently applied diagnostic modalities, several research groups focus on the potential of optical diagnostic techniques to contribute to the diagnostic process of renal tumors. They use the interaction of light with biological tissue to gather information on the optical properties of a tissue sample and therefore providing information on the histological composition of this tissue in a non-invasive manner and in real-time. In this review we provide an overview of novel diagnostic techniques starting with the future of conventional diagnostics like Contrast-enhanced ultrasonography (CEUS) and positron emission tomography-computed tomography (PET-CT) followed by optical technologies that are potentially employed in the nearby future to improve the diagnostic process of renal tumors with a focus on optical diagnostic techniques.