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

Management strategies and oncological follow-up of a bicentric French cohort of biopsied renal oncocytomas

OBJECTIVE

Renal oncocytoma is a benign renal tumour whose management remains heterogeneous and poorly codified. The aim of this study was to describe the management strategies and evolution of a cohort of biopsied renal oncocytomas.

MATERIALS AND METHODS

We retrospectively reviewed renal oncocytomas biopsied in 2 French academic centres between 2009 and 2016. Demographic, anatomopathological, radiological and operative (if operated) variables were collected and compared between patients operated on and those monitored in order to identify those associated with the management strategy and clinical course.

RESULTS

Fifty-three patients were included with a mean follow-up of 29.6±32.3 months. Patients operated on immediately were younger (mean 57±11.5 years vs 68±9.8 years; P=0.007), less comorbid (Charlson 2.8 vs 4; P=0.01) with a higher RENAL score (9 vs 6; P<0.001) and a larger tumour size (mean 58±27 vs 27±13mm; P=0.002). Of the 28 patients monitored, 23 (82%) were still being monitored at the end of the study. The median duration of monitoring was 17.56 months. For the cohort as a whole, the mean tumour growth rate was 2.6mm/year (±2.5).

CONCLUSION

The management of oncytomas was heterogeneous. Tumour size, patient age and his comorbidities, RENAL score and tumour growth rate were the criteria associated with surgical treatment.

LEVEL OF EVIDENCE: 4

Renal Mass Biopsy Prior to Surgical Excision: Practice, Diagnostic Performance, and Impact on Management in the UroCCR Registry (Ancillary Study No. 118)

Background and objective

A renal mass biopsy (RMB) is not systematically recommended before surgical excision of a renal mass, although it has demonstrated elevated accuracy in determining renal masses with low morbidity. Our aim was to determine the diagnostic accuracy of an RMB, the clinical and tumoral factors associated with RMB practice, and the impact of an RMB on renal cell carcinoma management in a contemporary prospective national registry-UroCCR (2010-2021).

Methods

We identified all patients with a single renal mass (pT1-4 N0-2 M0 or benign) who were treated surgically and stratified them according to the performance of a prior RMB. Patients treated by active surveillance, percutaneous ablative treatment, or stereotaxic radiotherapy were excluded. Diagnostic accuracy of an RMB was determined in the RMB group. Clinical and tumoral factors associated with the practice of RMBs were analyzed using logistic regression.

Key findings and limitations

In total, 9283 patients were included, who presented 1594 tumors (17%) with a prior RMB. RMBs were 92.4% contributive. The correlation between an RMB and excision in the determination of benign/malignant disease, histological subtype, and grade are, respectively, 96.9%, 86.4%, and 52.6%. The impact of an RMB versus no prior RMB was determined according to the rate of surgical excision for benign lesion and the rate of partial nephrectomy (63.9% vs 57.8%; p < 0.001).

Conclusions and clinical implications

An RMB is performed rarely when its diagnostic performance is high. A prior RMB significantly changes the management of localized renal masses, with fewer surgical procedures for benign renal masses and conservative treatment in a higher proportion of patients.

Patient summary

In a large and contemporary registry, we demonstrated that a renal mass biopsy has excellent diagnostic accuracy, significantly reduces renal surgery for benign masses and low-grade/stage renal cell carcinoma, and increases conservative surgical excision.

Renal mass biopsy - a practical and clinicopathologically relevant approach to diagnosis

Advancements in imaging modalities have increased the frequency of renal mass discovery. Imaging has typically been considered sufficient to guide management for a large proportion of these tumours, but renal mass biopsies (RMBs) have an increasing role in determining malignancy and can be a valuable tool for preventing unnecessary surgery in patients with benign tumours. A structured approach should be used to help to navigate the expanding repertoire of renal tumours, many of which are molecularly defined. In terms of tumour subtyping, the pathologist's strategy should focus on stratifying patients into clinically different prognostic groups according to our current knowledge of tumour behaviour, including benign, low-grade or indolent, intermediate malignant or highly aggressive. Crucial pathological features and morphological mimicry of tumours can alter the tumour's prognostic group. Thus, pathologists and urologists can use RMB to select patients with tumours at a reduced risk of progression, which can be safely managed with active surveillance within a tailored imaging schedule, versus tumours for which ablation or surgical intervention is indicated. RMB is also crucial in the oncological setting to distinguish between different high-grade tumours and guide tailored management strategies.

French AFU Cancer Committee Guidelines - Update 2024-2026: Management of kidney cancer

OBJECTIVE

To update the French recommendations for the management of kidney cancer.

METHODS

A systematic review of the literature was conducted for the period from 2014 to 2024. The most relevant articles concerning the diagnosis, classification, surgical treatment, medical treatment, and follow-up of kidney cancer were selected and incorporated into the recommendations. The recommendations have been updated specifying the level of evidence (strong or weak).

RESULTS

Kidney cancer following prolonged occupational exposure to trichloroethylene should be considered an occupational disease. The reference examination for the diagnosis and staging of kidney cancer is the contrast-enhanced thoraco-abdominal CT scan. PET scans are not indicated in the staging of kidney cancer. Percutaneous biopsy is recommended in situations where its results will influence therapeutic decisions. It should be used to reduce the number of surgeries for benign tumors, particularly avoiding unnecessary radical nephrectomies. Kidney tumors should be classified according to the pTNM 2017 classification, the WHO 2022 classification, and the ISUP nucleolar grade. Metastatic kidney cancers should be classified according to IMDC criteria. Surveillance of tumors smaller than 2cm should be prioritized and can be offered regardless of patient age. Robot-assisted laparoscopic partial nephrectomy is the reference surgical treatment for T1 tumors. Ablative therapies and surveillance are options for elderly patients with comorbidities for tumors larger than 2cm. Stereotactic radiotherapy is an option to discuss for treating localized kidney tumors in patients not eligible for other treatments. Radical nephrectomy is the first-line treatment for locally advanced localized cancers. Pembrolizumab is recommended for patients at high risk of recurrence after surgery for localized kidney cancer. In metastatic patients, cytoreductive nephrectomy can be immediate in cases of good prognosis, delayed in cases of intermediate or poor prognosis for patients stabilized by medical treatment, or as "consolidation" in patients with complete or major partial response at metastatic sites after systemic treatment. Surgical or local treatment of metastases can be proposed for single lesions or oligometastases. Recommended first-line drugs for metastatic clear cell renal carcinoma are combinations of axitinib/pembrolizumab, nivolumab/ipilimumab, nivolumab/cabozantinib, and lenvatinib/pembrolizumab. Patients with non-clear cell metastatic kidney cancer should be presented to the CARARE Network and prioritized for inclusion in clinical trials.

CONCLUSION

These updated recommendations are a reference that will enable French and French-speaking practitioners to optimize their management of kidney cancer.

[89Zr]Zr-girentuximab for PET-CT imaging of clear-cell renal cell carcinoma: a prospective, open-label, multicentre, phase 3 trial

BACKGROUND

With limitations of conventional imaging and biopsy, accurate, non-invasive techniques to detect clear-cell renal cell carcinoma in patients with renal masses remain an unmet need. 89Zr-labelled monoclonal antibody ([89Zr]Zr-girentuximab) has high affinity for carbonic anhydrase 9, a tumour antigen highly expressed in clear-cell renal cell carcinoma. We aimed to evaluate [89Zr]Zr-girentuximab PET-CT imaging for detection and characterisation of clear-cell renal cell carcinoma.

METHODS

ZIRCON was a prospective, open-label, multicentre, phase 3 trial conducted at 36 research hospitals and practices across nine countries (the USA, Australia, Canada, the UK, Türkiye, Belgium, the Netherlands, Spain, and France). Patients aged 18 years or older with an indeterminate renal mass 7 cm or smaller (cT1) suspicious for clear-cell renal cell carcinoma and scheduled for nephrectomy received a single dose of [89Zr]Zr-girentuximab (37 MBq ±10%; 10 mg girentuximab) intravenously followed by abdominal PET-CT imaging 5 days (±2 days) later. Surgery was performed no later than 90 days after administration of [89Zr]Zr-girentuximab. Blinded central review, conducted by three independent readers, determined the histology from surgical samples. The coprimary endpoints, determined for each individual reader, were the sensitivity and specificity of [89Zr]Zr-girentuximab PET-CT imaging to detect clear-cell renal cell carcinoma, with histopathological confirmation as standard of truth. Analyses were on the full analysis set of patients, defined as patients who had evaluable PET-CT imaging and a confirmed histopathological diagnosis. The trial is registered with ClinicalTrials.gov, NCT03849118, and EUDRA Clinical Trials Register, 2018-002773-21, and is closed to enrolment.

FINDINGS

Between Aug 14, 2019, and July 8, 2022, 371 patients were screened for eligibility, 332 of whom were enrolled. 300 patients received [89Zr]Zr-girentuximab (214 [71%] male and 86 [29%] female). 284 (95%) evaluable patients were included in the primary analysis. The mean sensitivity was 85·5% (95% CI 81·5-89·6) and mean specificity was 87·0% (81·0-93·1). No safety signals were observed. Most adverse events were not or were unlikely to be related to [89Zr]Zr-girentuximab, with most (193 [74%] of 261 events) occurring during or after surgery. The most common grade 3 or worse adverse events were post-procedural haemorrhage (in six [2%] of 261 patients), urinary retention (three [1%]), and hypertension (three [1%]). In 25 (8%) of 300 patients, 52 serious adverse events were reported, of which 51 (98%) occurred after surgery. There were no treatment-related deaths.

INTERPRETATION

Our results suggest that [89Zr]Zr-girentuximab PET-CT has a favourable safety profile and is a highly accurate, non-invasive imaging modality for the detection and characterisation of clear-cell renal cell carcinoma, which has the potential to be practice changing.

FUNDING

Telix Pharmaceuticals.

Stepwise algorithm using computed tomography and magnetic resonance imaging for differential diagnosis of fat-poor angiomyolipoma in small renal masses: A prospective validation study

OBJECTIVES

To validate the diagnostic accuracy of a stepwise algorithm to differentiate fat-poor angiomyolipoma (fp-AML) from renal cancer in small renal masses (SRMs).

METHODS

We prospectively enrolled 223 patients with solid renal masses <4 cm and no visible fat on unenhanced computed tomography (CT). Patients were assessed using an algorithm that utilized the dynamic CT and MRI findings in a stepwise manner. The diagnostic accuracy of the algorithm was evaluated in patients whose histology was confirmed through surgery or biopsy. The clinical course of the patients was further analyzed.

RESULTS

The algorithm classified 151 (68%)/42 (19%)/30 (13%) patients into low/intermediate/high AML probability groups, respectively. Pathological diagnosis was made for 183 patients, including 10 (5.5%) with fp-AML. Of these, 135 (74%)/36 (20%)/12 (6.6%) were classified into the low/intermediate/high AML probability groups, and each group included 1 (0.7%)/3 (8.3%)/6 (50%) fp-AMLs, respectively, leading to the area under the curve for predicting AML of 0.889. Surgery was commonly opted in the low and intermediate AML probability groups (84% and 64%, respectively) for initial management, while surveillance was selected in the high AML probability group (63%). During the 56-month follow-up, 36 (82%) of 44 patients initially surveyed, including 13 of 18 (72%), 6 of 7 (86%), and 17 of 19 (89%) in the low/intermediate/high AML probability groups, respectively, continued surveillance without any progression.

CONCLUSIONS

This study confirmed the high diagnostic accuracy for differentiating fp-AMLs. These findings may help in the management of patients with SRMs.

Long-Term Oncological and Functional Outcomes after Laparoscopic Partial Nephrectomy with Hyperselective Embolization of Tumor Vessels in a Hybrid Operating Room

Laparoscopic partial nephrectomy (LPN) after hyperselective embolization of tumor vessels (HETV) in a hybrid operating room (HOR) that combines traditional surgical equipment with advanced imaging technology, is a non-clamping surgical approach to treat localized kidney tumors that has shown promising short-term results. The aim of this study was to evaluate the long-term oncological and functional outcomes of this procedure. All consecutive patients treated for a localized kidney tumor by LPN after HETV between May 2015 and October 2022 in a single academic institution were included in the study. Clinical, pathological and biological data were collected prospectively in the uroCCR database. We evaluated intraoperative data, postoperative complications, surgical margin and modification of renal function after surgery. We included 245 patients. The median tumor size was 3.2 (2.5-4.4) cm. The R.E.N.A.L. complexity was low, medium and high for 104 (43.5%), 109 (45.6%) and 26 (10.9%) patients, respectively. Median LPN time was 75 (65-100) min and median blood loss was 100 (50-300) mL. Surgical postoperative complications occurred in 56 (22.9%) patients with 17 (5.7%) major complications. The median Glomerular Function Rate variation at 6 months was -7.5 (-15--2) mL/min. Malignant tumors were present in 211 (86.1%) patients, and 12 (4.9%) patients had positive surgical margins. After a median follow-up of 27 (8-49) months, 20 (8.2%) patients had a tumor recurrence and 4 (1.6%) died from cancer. At 5 years, disease free survival, cancer specific survival and overall survival rates were 84%, 96.8% and 88.3%, respectively. Performing LPN after HETV in a HOR is a safe and efficient non-clamping approach to treat localized kidney tumors.