Active surveillance is suitable for intermediate term follow-up of renal oncocytoma diagnosed by percutaneous core biopsy

Oncocytic Carcinoma with Liver Metastasis: Unusual Treatment Strategies and Clinical Insights-A Case Report and Review of the Literature

We report a distinctive case of malignant oncocytic carcinoma originating in the pancreas, an organ rarely associated with such tumours. We discuss the diagnostic journey, highlighting the tumour's resemblance to renal cell carcinoma but without renal involvement. A significant aspect of this case is the successful and sustained response to combined immunotherapy and tyrosine kinase inhibitors, demonstrating a potential therapeutic pathway for similar rare cases. This study contributes to a deeper understanding of pancreatic oncocytic tumours and their management.

Stability of renal parenchymal volume and function during active surveillance of renal oncocytoma patients

INTRODUCTION AND OBJECTIVE

To evaluate whether significant loss in ipsilateral renal parenchymal volume (IRPV) and renal function occurs during active surveillance (AS) of renal oncocytoma (RO) patients.

METHODS

Renal function (estimated glomerular filtration rate, eGFR) dynamics were retrospectively analyzed in 32 consecutive biopsy-diagnosed RO patients managed with AS at a National Comprehensive Cancer Network institute. Three-dimensional kidney and tumor reconstructions were generated and IRPV was calculated using volumetry software (Myrian®) for all patients with manually estimated RO growth >+10 cm3. GFR and IRPV were compared at AS initiation vs. the last follow-up using 2-sided paired t-tests. The correlation between change in IRPV and change in RO size or GFR was tested using a Spearman coefficient.

RESULTS

With median follow-up of 37 months, there was no significant change between initial vs. last eGFR (median 71.0 vs. 70.5 ml/min/1.73 m2, P = 0.50; median change -3.0 ml/min/1.73 m2). Among patients (n = 17) with RO growth >+10 cm3 during AS (median growth +28.6 cm3, IQR +16.9- + 46.5 cm3), IRPV generally remained stable (median change +0.5%, IQR -1.2%- + 1.2%), with only 2 cases surpassing 5% loss. No IRPV loss was detected among any patient within the top tertile of RO growth magnitude. RO growth magnitude did not correlate with loss of either IRPV (ρ = -0.30, P = 0.24) or eGFR (ρ = -0.16, P = 0.40), including among patient subsets with lower initial eGFR. Study limitations include a lack of long-term follow-up.

CONCLUSIONS

Volumetry is a promising novel tool to measure kidney and tumor tissue changes during AS. Our study using volumetry indicates that clinically significant loss of IRPV or eGFR is uncommon and unrelated to tumor growth among untreated RO patients with intermediate follow-up. These findings support that AS is in general functionally safe for RO patients, however longer study is needed to determine safety durability, particularly among uncommon ≥cT2 RO variants.

Oncocytoma on renal mass biopsy: is it still the same histology when surgery is performed? Results from UroCCR-104 study

PURPOSE

To describe clinical features of patients with oncocytoma on renal biopsy (RMB), correlation with final histology on surgically treated patients, and predictive factors of discrepancy between RMB and final histology.

METHODS

This was a retrospective study conducted in the framework of the UroCCR project (NCT03293563). All tumors with oncocytoma on RMB were selected and all pathological reports were reviewed. Patients with the RMB simultaneously performed with a focal treatment, synchronous bilateral tumors and ambiguous RMB report were excluded. Discrepancy between RMB and definitive histology was evaluated using a uni- and multivariable logistic regression analyses model.

RESULTS

Overall, 119 tumors with oncocytoma on RMB, from 15 centers, were included. Of those, 54 (45.4%) had upfront surgery and 65 (54.6%) had active surveillance (AS). In renal masses with initial active surveillance, with a median follow-up of 28 months, 23 (19.3%) underwent surgery, 4 (3.4%) received focal treatment and 38 (31.9%) remained on AS. On final pathology, only 51 of the 75 surgically treated tumors (68.0%) had oncocytoma, while 24 presented malignant tumors (mainly chromophobe carcinoma (19.2%), and hybrid oncocytic/chromophobe tumor (HOCT) (6.8%)) leading to a discrepancy of 32.0% between RMB and final pathology. The only predictive factor of a discrepancy between RMB and definitive histology was a biopsy done outside of the center (Odds ratio: 3.22 [95%-confidence interval: 1.08-9.61], p = 0.03).

CONCLUSION

Despite the increase of RMB in more and more centers, histologic discrepancy between RMB and definitive histology remains significant. This information should be discussed with patients and taken into consideration before treatment decision.

Protocol for a MULTI-centre feasibility study to assess the use of 99mTc-sestaMIBI SPECT/CT in the diagnosis of kidney tumours (MULTI-MIBI study)

INTRODUCTION

The incidence of renal tumours is increasing and anatomic imaging cannot reliably distinguish benign tumours from renal cell carcinoma. Up to 30% of renal tumours are benign, with oncocytomas the most common type. Biopsy has not been routinely adopted in many centres due to concerns surrounding non-diagnostic rate, bleeding and tumour seeding. As a result, benign masses are often unnecessarily surgically resected. ^99mTc-sestamibi SPECT/CT has shown high diagnostic accuracy for benign renal oncocytomas and other oncocytic renal neoplasms of low malignant potential in single-centre studies. The primary aim of MULTI-MIBI is to assess feasibility of a multicentre study of ^99mTc-sestamibi SPECT/CT against a reference standard of histopathology from surgical resection or biopsy. Secondary aims of the study include obtaining estimates of ^99mTc-sestamibi SPECT/CT sensitivity and specificity and to inform the design and conduct of a future definitive trial.

METHODS AND ANALYSIS

A feasibility prospective multicentre study of participants with indeterminate, clinical T1 renal tumours to undergo ^99mTc-sestamibi SPECT/CT (index test) compared with histopathology from biopsy or surgical resection (reference test). Interpretation of the index and reference tests will be blinded to the results of the other. Recruitment rate as well as estimates of sensitivity, specificity, positive and negative predictive value will be reported. Semistructured interviews with patients and clinicians will provide qualitative data to inform onward trial design and delivery. Training materials for ^99mTc-sestamibi SPECT/CT interpretation will be developed, assessed and optimised. Early health economic modelling using a decision analytic approach for different diagnostic strategies will be performed to understand the potential cost-effectiveness of ^99mTc-sestamibi SPECT/CT.

ETHICS AND DISSEMINATION

Ethical approval has been granted (UK HRA REC 20/YH/0279) protocol V.5.0 dated 21/6/2022. Study outputs will be presented and published nationally and internationally.

TRIAL REGISTRATION NUMBER

ISRCTN12572202.

Reliability and Management Outcomes Following a Percutaneous Biopsy Diagnosis of Oncocytoma: A 15-year Retrospective Analysis

Background There is uncertainty in the management of renal masses diagnosed as oncocytomas with image-guided percutaneous biopsy. Purpose To assess the reliability of a diagnosis of oncocytoma based on image-guided percutaneous renal mass biopsy and evaluate patient outcomes following different management strategies. Materials and Methods In this retrospective study, image-guided percutaneous biopsy pathology reports from April 2004 to April 2019 were searched for keywords "oncocytoma" and "oncocytic neoplasm" and compared with surgical pathology or repeat biopsy results. Patients with at least 12 months of clinical follow-up and known cause of death were grouped according to management strategies, and disease-specific survival and metastatic renal cell carcinoma (RCC)-free survival were compared. Mass growth rates were calculated with use of a normal linear mixed model. Results The database yielded 160 biopsy reports of 149 renal masses in 139 patients; 149 masses were categorized as oncocytoma (n = 107), likely oncocytoma (n = 12), oncocytic neoplasm (n = 28), and indeterminate with oncocytoma in differential (n = 2). Biopsied masses categorized as oncocytoma or likely oncocytoma were oncocytomas in 16 of 17 masses (94%) based on surgical pathology or repeat biopsy; four of eight masses (50%) categorized as oncocytic neoplasms were low-grade RCCs. Outcome analysis included 121 patients (mean age ± SD, 68 years ± 9.1; 82 men); 80 patients initially underwent active surveillance (11 were later treated), 33 underwent ablation, and eight underwent surgery. Disease-specific survival and metastatic-free survival were 100% after each management strategy (median follow-up, 86.6 months; range, 14.2-207.9 months). Mass growth rate (mean, 1.7 mm per year) showed no evidence of a significant difference among biopsy result categories (P = .37) or initial (P = .84) or final management strategies (P = .11). Conclusion Image-guided percutaneous biopsy diagnosis of renal oncocytoma was reliable. Although some masses diagnosed as oncocytic neoplasms were low-grade renal cell carcinomas (RCCs) at final diagnosis, no patients died of RCC, including those managed with active surveillance. © RSNA, 2023 See also the editorial by Lockhart in this issue.

Benefit and Harm of Active Surveillance for Biopsy-proven Renal Oncocytoma: A Systematic Review and Pooled Analysis

Context

Active surveillance (AS) of biopsy-proven renal oncocytomas may reduce overtreatment. However, on biopsy, the risk of misdiagnosis owing principally to entities with peculiar hybrids and overlap morphology, and phenotypes argues for early intervention.

Objective

To assess the benefit and harm of AS in biopsy-proven renal oncocytoma.

Evidence acquisition

A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). We systematically searched PubMed, Scopus, and Web of Science databases from September 26 up to October 2021, for studies that analyzed the outcomes of AS in patients with biopsy-proven renal oncocytoma.

Evidence synthesis

A total of ten studies with 633 patients met our inclusion criteria and were included for analysis. After a median follow-up of 34.5 mo (95% confidence interval [CI] 30.6–38.4), the overall definitive treatment rate from AS to definitive treatment was 17.3% (n = 75/433, six studies). The pooled pathological agreement between the initial renal mass biopsy and the surgical pathology report was 91.1%. The main indications for surgery during follow-up were rapid tumor growth and patient request. The pooled median growth rate was 1.55 mm/yr (95% CI 0.9–2.2). No metastasis or death related to renal oncocytoma was reported.

Conclusions

Annual tumor growth of biopsy-proven renal oncocytoma is low. AS is oncologically safe, with favorable compliance of patients. Crossover to definitive treatment revealed a strong concordance between biopsy and final pathology. Further studies on the long-term outcomes of AS are needed.

Patient summary

In this study, we examined the benefit and harm of active surveillance (AS) in biopsy-proven oncocytoma. Based on the available data, AS appears oncologically safe and may represent a promising alternative to immediate treatment. Patients should be included in AS decision discussions.

Real world outcomes of biopsy‐proven oncocytic neoplasm of the kidney managed by surveillance

Objectives

To evaluate outcomes of patients diagnosed with oncocytic renal neoplasms on routine renal mass biopsy and to describe the natural history of these tumours when managed with surveillance as opposed to immediate intervention. To report disease‐specific survival.

Patients and methods

Patients were identified from a retrospective review of pathology databases from three tertiary referral centres that utilise renal mass biopsy in routine clinical practice. All patients with biopsy‐proven oncocytic tumours were included and a retrospective review of online patient records was undertaken.

Results

There were 184 biopsy‐proven oncocytic renal neoplasms identified in 172 patients. There were two biopsy complications (both pneumothorax, Clavien–Dindo Grade I). Of these lesions, 135 were reported as oncocytomas or oncocytic renal neoplasms that were not further classified and 37 were reported as chromophobe carcinoma (ChRCC). The median age at diagnosis was 70 (33–88). The average tumour diameter at diagnosis was 33 mm. One hundred seven tumours were initially managed with surveillance (including 13 ChRCC) with a minimum follow‐up of 6 months and a median of 39 months (6–144) whereas 49 patients underwent immediate treatment. The mean growth rate across all oncocytic renal neoplasms managed by surveillance was 3 mm/year. There was no statistically significant difference in growth rates between oncocytic renal neoplasms and ChRCC. Thirteen patients with oncocytic renal neoplasms initially managed by surveillance moved on to an active management strategy during follow‐up. The clinical indication given for a change from surveillance was tumour growth in 12 cases and patient choice in 1 case. Where definitive pathology was available, there was 85% concordance with the biopsy. There were no cases of development of metastatic disease or disease‐related morbidity or mortality during the study.

Conclusions

This multicentre retrospective cohort study supports the hypothesis that selected biopsy‐proven oncocytic renal neoplasms can be safely managed with surveillance in the medium term. Routine renal mass biopsy may reduce surgery for benign or indolent renal tumours and the potential associated morbidity for these patients.

Application of Mass Spectrometry Imaging in Uro-Oncology: Discovering Potential Biomarkers

A growing need is emerging worldwide for new molecular markers which could enhance the accuracy of diagnostic and therapeutic methods for detecting urogenital cancers. Mass spectrometry imaging (MSI) is a very promising tool in this regard. In this review, we attempt to provide a subjective summary of the latest publications on potential biomarkers of renal, bladder, prostate, and testicular malignancies detected with MSI through the eyes of a clinical urologist.

Renal Oncocytoma: The Diagnostic Challenge to Unmask the Double of Renal Cancer

Renal oncocytoma represents the most common type of benign neoplasm that is an increasing concern for urologists, oncologists, and nephrologists due to its difficult differential diagnosis and frequent overtreatment. It displays a variable neoplastic parenchymal and stromal architecture, and the defining cellular element is a large polygonal, granular, eosinophilic, mitochondria-rich cell known as an oncocyte. The real challenge in the oncocytoma treatment algorithm is related to the misdiagnosis due to its resemblance, at an initial radiological assessment, to malignant renal cancers with a completely different prognosis and medical treatment. Unfortunately, percutaneous renal biopsy is not frequently performed due to the possible side effects related to the procedure. Therefore, the majority of oncocytoma are diagnosed after the surgical operation via partial or radical nephrectomy. For this reason, new reliable strategies to solve this issue are needed. In our review, we will discuss the clinical implications of renal oncocytoma in daily clinical practice with a particular focus on the medical diagnosis and treatment and on the potential of novel promising molecular biomarkers such as circulating microRNAs to distinguish between a benign and a malignant lesion.

Growth and renal function dynamics of renal oncocytomas in patients on active surveillance

OBJECTIVES

To study the natural history of renal oncocytomas and address indications for intervention by determining how growth is associated with renal function over time, the reasons for surgery and ablation, and disease-specific survival.

PATIENTS AND METHODS

The study was conducted in a retrospective cohort of consecutive patients with renal oncocytoma on active surveillance reviewed at the Specialist Centre for Kidney Cancer at the Royal Free London NHS Foundation Trust (2012 to 2019). Comparison between groups was performed using Mann-Whitney U-tests and chi-squared tests. A mixed-effects model with a random intercept for patient was used to study the longitudinal association between tumour size and estimated glomerular filtration rate (eGFR).

RESULTS

Longitudinal data from 98 patients with 101 lesions were analysed. Most patients were men (68.3%) and the median (interquartile range [IQR]) age was 69 (13) years. The median (IQR) follow-up was 29 (26) months. Most lesions were small renal masses, and 24% measured over 4 cm. Over half (64.4%) grew at a median (IQR) rate of 2 (4) mm per year. No association was observed between tumour size and eGFR over time (P = 0.871). Nine lesions (8.9%) were subsequently treated. Two deaths were reported, neither were related to the diagnosis of renal oncocytoma.

CONCLUSION

Natural history data from the largest active surveillance cohort of renal oncocytomas to date show that renal function does not seem to be negatively impacted by growing oncocytomas, and confirms clinical outcomes are excellent after a median follow-up of over 2 years. Active surveillance should be considered the 'gold standard' management of renal oncocytomas up to 7cm.

Active surveillance for bilateral renal oncocytomas already resected on one side: a case report

INTRODUCTION

To report our experience of active surveillance of new bilateral masses after left laparoscopic partial nephrectomy for oncocytoma.

METHOD

A 67-year old man underwent left laparoscopic partial nephrectomy for a renal mass and histology confirmed oncocytoma. At follow-up magnetic resonance imaging (MRI) showed new renal bilateral masses: hence, sonogram-guided percutaneous core renal biopsies were performed confirming the presence of oncocytoma in both kidneys. A re-biopsy was required because of an increasing of the left mass while a histological was also consistent with oncocytoma.

RESULT

At follow of 8 years the patient is well and shows a normal renal function.

CONCLUSION

Oncocytomas show minimal growth rate or progression. MRI has an important role in the appropriate follow-up of renal oncocytomas. Patients with biopsy proven oncocytoma may be managed conservatively by active surveillance (AS).

Renal Oncocytoma: An Algorithm for Diagnosis and Management

Renal oncocytoma is an uncommon tumor that exhibits numerous features which are characteristic but not necessarily unique. Percutaneous biopsy is a safe method of diagnosis. However, differentiation from other tumor subtypes often requires sophisticated analysis and is not universally feasible. This is why, surgical management can be considered as a first-line treatment or after surveillance. Potential triggers for change in management are: tumor size >3 cm, stage progression, kinetics of size progression (>5 mm/y), and clinical change in patient or tumor factors. Long-term follow-up data are lacking and greater centralization should be considered to reach adequate management.

[Evolution of followed renal oncocytomas]

INTRODUCTION

Oncocytomas are primitive kidney tumours, considered benign but their evolution is not fully established. The local progression is generally admitted but few data explain what makes a oncocytoma to grow more or less quickly. The objective of our study is to analyse the evolution of followed renal oncocytomas after histologic confirmation and to identify factors that can influence their growth.

MATERIAL AND METHODS

This is a retrospective study in two centers (North Hospital and Hospital of the Conception of Marseille). All patients with renal oncocytoma diagnosed with percutaneous biopsy from September 2010 to April 2016 and followed for more than one year were included. Epidemiological, histological, and morphological data were collected at diagnosis, during follow-up and in case of strategy change (intervention). Statistical analysis of factors influencing oncocytomes growth was based on the Pearson correlation test.

RESULTS

Fifty-three patients were included. The median age for diagnosis was 65 years [39-85]. The sex ratio H/F was 6/5. The median follow-up was 34 months [12-180]. The average diagnosis size was 29 mm [12-90]. Thirteen patients (25%) were treated secondarily, including 70% by conservative treatment. The average growth was 0.25 (±0.23) cm/yr. The patients treated were younger and had a higher growth rate than the untreated (0.48±0.23cm/yr versus 0.18±0.18cm/yr, P<0,001). According to Pearson's analysis, there was a positive linear relationship (R=0.27, P=0.047) between velocity and initial size and a negative linear relationship (ρ=-0.44, P<0.001) between velocity and age at diagnosis. So tumor growth was faster if the patients were young and the tumor voluminous at diagnosis.

DISCUSSION

Rapid growth often leads to a cessation of surveillance in favour of an intervention strategy. For young patients, conservative treatment (partiel nephrectomy or ablative treatment) in the medium term is likely to be preferred, but for elderly patients or with important comorbidities follow-up is an alternative to an invasive attitude.

LEVEL OF EVIDENCE

3.

[Retrospective study of diagnosis and treatment of renal oncocytoma]

OBJECTIVE

To summarize the experience of diagnosis and surgical treatment of renal oncocytoma, and to evaluate the surgical results based on follow-up results, in order to find the best strategy.

METHODS

In the study, 21 cases with renal oncocytoma from December 2003 to April 2016 in Peking University Third Hospital were retrospectively analyzed, including 4 males, and 17 females, with 10 cases on the right side and 11 cases on the left side. Their age was between 15 to 80 years (average: 58 years). Ultrasound or CT examination after admission was conducted. Ultrasound examination showed solid nodules. CT manifestations were solid masses with enhancement, and the tumor size was between 1.5 cm to 6.5 cm (average: 3.3 cm). Of the 21 cases, 9 were located in the middle of kidney, 7 were located in the upper pole, and 5 were located in the lower pole. After preoperative examination, according to the size and location of the tumor, laparoscopic partial nephrectomy or laparoscopic nephrectomy was performed, respectively.

RESULTS

All the operations were successful, in which 17 cases underwent laparoscopic partial nephrectomy (including 3 cases which were converted to open surgery), and 4 cases underwent laparoscopic radical nephrectomy. The operation time ranged from 75 to 274 min (mean: 144 min), and the blood loss ranged from 10 to 1 000 mL (mean: 115 mL). The postoperative hospital stay time ranged from 6 to 13 d (average: 8.2 d). The pathological results were all renal oncocytoma. In the study, 17 cases were followed up while 4 cases were lost to follow-up. The follow-up time ranged from 12 to 175 months (mean: 44 months). One case died in 20 months after operation with unknown reason, and there were no recurrence or metastasis in the other 16 cases.

CONCLUSION

Renal oncocytoma is a benign tumor with good prognosis. Enhanced CT is an effective diagnostic method in assistant examination, but it is difficult to differentiate clear cell carcinoma only from the naked eye. It is worthwhile to measure CT value at different stages of the tumor by picture archiving and communication systems (PACS), and to compare with CT value of adjacent kidney tissue may improve the diagnostic efficiency of CT. Laparoscopic surgery is an effective treatment for renal oncocytoma. We recommend laparoscopic partial nephrectomy for the patients with renal oncocytoma as the best choice if conditions permit.

Roles for active surveillance in renal cancer

PURPOSE OF REVIEW

With this review, we describe the most recent advances in active surveillance as well as diagnosis and management of small renal masses (SRMs).

RECENT FINDINGS

We discuss diagnosis, differentiation of solid from cystic lesions, risk prediction and treatment of the SRM. A better understanding of the disease facilitates the use of more conservatory treatments, such as active surveillance. Active surveillance has been increasingly accepted not only for SRM, but also for larger tumors and even metastatic patients. Exiting advances in risk prediction will help us define which patients can be safely managed with active surveillance and which require immediate treatment. Meanwhile, the use of renal tumor biopsies is still an important tool for these cases.

SUMMARY

Active surveillance is an option for many patients with renal masses. Noninvasive methods for diagnosis and risk prediction are being developed, but meanwhile, renal tumor biopsy is a useful tool. A better understanding of the disease increases the number of patients who can undergo active surveillance fully certain of the safety of their management.

Palpable Abdominal Mass is a Renal Oncocytoma: Not All Large Renal Masses are Malignant

A 59-year-old woman presented with abdominal pain and a palpable abdominal mass. Initial imaging revealed a 14cm solid, enhancing renal mass and suspicion for liver and bone metastases. Family history included a brother with clear cell renal cell carcinoma and mother with glioblastoma multiforme. After liver biopsy was inconclusive, she underwent radical nephrectomy with final pathologic diagnosis of oncocytoma. Renal oncocytoma is the most common benign renal tumor but remains difficult to distinguish clinically and radiographically from renal cell carcinoma. Should urologists use renal mass biopsy even more frequently prior to surgical intervention?

Quality of Health Information on the Internet for Prostate Cancer

Introduction

To compare (1) the quality of prostate cancer health information on the Internet, (2) the difference in quality between websites appearing earlier or later in the search, and (3) the sources of sponsorship for each of these websites.

Materials and methods

The top 150 listed websites on the Google search engine for each of the 11 search terms related to prostate cancer were analysed. Quality was assessed on whether the website conforms to the principles of the Health On the Net Foundation. Each of these websites was then reviewed to determine the main source of sponsorship. Statistical analysis was performed to determine if the proportion of HON accreditation varied among the different cohorts of listed websites and among the 11 search terms used.

Results

In total, 1650 websites were analysed. Among these, 10.5% websites were HON-accredited. The proportion of HON-accredited websites for individual search terms ranged from 3.3% to 19.3%. In comparison with the search term of "Prostate cancer," four search terms had statistically significant odds ratio of the rate of HON accreditation. Websites 51-150 were statistically less likely to have HON accreditation than websites 1-50. The top three website sponsors were journal/universities (28.8%), commercial (28.1%), and physician/surgeon (26.9%).

Conclusions

The lack of validated and unbiased websites for prostate cancer is concerning especially with increasing use of the Internet for health information. Websites sponsored or managed by the government and national departments were most likely to provide impartial health information for prostate cancer. We need to help our patients identify valid and unbiased online health resources.

Oncocytoma: A Differential Consideration for an Incidentally Detected FDG-Avid Renal Mass on PET/CT

Renal oncocytoma is a benign renal neoplasm that is often discovered incidentally and closely mimics renal cell carcinoma on common imaging modalities such as computed tomography (CT) and magnetic resonance imaging (MRI). Due to the inability to reliably distinguish between these benign and malignant lesions with imaging, both are typically treated as if they are malignant. Hypermetabolic activity of renal oncocytomas is not frequently encountered because positron emission tomography (PET) is not a standard modality for imaging primary renal tumors. We present a case of a 65 year-old female with a history of thyroid cancer who had an incidentally discovered hypermetabolic renal mass on surveillance PET-CT imaging. Due to the concern for a primary renal malignancy or metastatic disease, the mass was resected and proven to be an oncocytoma on pathologic review.

Surgical histopathology for suspected oncocytoma on renal mass biopsy: a systematic review and meta-analysis

To estimate the proportion of oncocytic renal neoplasms diagnosed on renal mass biopsy (RMB) confirmed on surgical pathology, a systematic review of MEDLINE, Embase, and the Cochrane databases (1997 to 1 July 2016) was conducted quantifying all cases of reported oncocytic renal neoplasms on RMB suggestive of an oncocytoma. In addition, institutional data was assessed to identify additional cases. Concordance with surgical histopathology (positive predictive value [PPV]) was evaluated for patients undergoing surgery by performing a meta-analysis. In all, 10 RMB series, including institutional data, were included in the meta-analysis with 205 RMBs identifying oncocytic renal neoplasms and 46 (22.4%) proceeding to surgery. One additional study identified two neoplasms not captured by the primary RMB series for a total of 48 unique lesions included in the analysis. Surgical pathology showed oncocytoma (64.6%), chromophobe renal cell carcinoma (RCC; 12.5%), other RCC (12.5%), hybrid oncocytic/chromophobe tumour (6.3%), and other benign lesions (4.2%). PPV of oncocytoma on RMB was 67% (95% confidence interval 34-94%) with significant heterogeneity between studies (I² = 71.8%, P < 0.01). Risk of bias was judged to be low for four of the 10 series. Confidently diagnosing a localised renal mass as a benign lesion, such as an oncocytoma, has implications for the ultimate management strategy a patient will undergo. RMB was found to be unreliable in confidently diagnosing a localised renal mass as an oncocytoma, with one in four found to be RCC on surgical pathology. Patients and physicians should be aware of the uncertainty in diagnosis when considering management strategies.

Comparing renal function preservation after laparoscopic radio frequency ablation assisted tumor enucleation and laparoscopic partial nephrectomy for clinical T1a renal tumor: using a 3D parenchyma measurement system

PURPOSE

To compare the renal function preservation between laparoscopic radio frequency ablation assisted tumor enucleation and laparoscopic partial nephrectomy.

METHODS

Data were analyzed from 246 patients who underwent laparoscopic radio frequency ablation assisted tumor enucleation and laparoscopic partial nephrectomy for solitary cT1a renal cell carcinoma from January 2013 to July 2015. To reduce the intergroup difference, we used a 1:1 propensity matching analysis. The functional renal parenchyma volume preservation were measured preoperative and 12 months after surgery. The total renal function recovery and spilt GFR was compared. Multivariable logistic analysis was used for predictive factors for renal function decline.

RESULTS

After 1:1 propensity matching, each group including 100 patients. Patients in the laparoscopic radio frequency ablation assisted tumor enucleation had a smaller decrease in estimate glomerular filtration rate at 1 day (-7.88 vs -20.01%, p < 0.001), 3 months (-2.31 vs -10.39%, p < 0.001), 6 months (-2.16 vs -7.99%, p = 0.015), 12 months (-3.26 vs -8.03%, p = 0.012) and latest test (-3.24 vs -8.02%, p = 0.040), also had better functional renal parenchyma volume preservation (89.19 vs 84.27%, p < 0.001), lower decrease of the spilt glomerular filtration rate (-9.41 vs -17.13%, p < 0.001) at 12 months. The functional renal parenchyma volume preservation, warm ischemia time and baseline renal function were the important independent factors in determining long-term functional recovery.

CONCLUSIONS

The laparoscopic radio frequency ablation assisted tumor enucleation technology has unique advantage and potential in preserving renal parenchyma without ischemia damage compared to conventional laparoscopic partial nephrectomy, and had a better outcome, thus we recommend this technique in selected T1a patients.