Renal mass biopsy for the small renal mass

Opponents of premanagement biopsy of small renal masses are not difficult to find. Many urologists contend that the benefits of biopsy do not outweigh the risks, arguing that the results do not influence management substantially and that the most useful information from renal mass biopsy can be attained with advanced imaging. In this article, we develop the counter arguments and demonstrate that renal mass biopsy should be implemented into the small renal mass management algorithm.     

Small renal mass biopsy – how,what and when: report from an international consensus panel

• To discuss the use of renal mass biopsy (RMB) for small renal masses (SRMs), formulate technical aspects, outline potential pitfalls and provide recommendations for the practicing clinician.
• The meeting was conducted as an informal consensus process and no scoring system was used to measure the levels of agreement on the different topics.
• A moderated general discussion was used as the basis for consensus and arising issues were resolved at this point.
• A consensus was established and lack of agreement to topics or specific items was noted at this point.
• Recommended biopsy technique: at least two cores, sampling different tumour regions with ultrasonography being the preferred method of image guidance.
• Pathological interpretation: ‘non‐diagnostic samples’ should refer to insufficient material, inconclusive and normal renal parenchyma. For non‐diagnostic samples, a repeat biopsy is recommended. Fine‐needle aspiration may provide additional information but cannot substitute for core biopsy.
• Indications for RMB: biopsy is recommended in most cases except in patients with imaging or clinical characteristics indicative of pathology (syndromes, imaging characteristics) and cases whereby conservative management is not contemplated. RMB is recommended for active surveillance but not for watchful‐waiting candidates.
• We report the results of an international consensus meeting on the use of RMB for SRMs, defining the technique, pathological interpretation and indications.

     

Techniques, safety and accuracy of sampling of renal tumors by fine needle aspiration and core biopsy

PURPOSE: The incidence of renal cell carcinoma is increasing worldwide and there are new treatments for localized as well as metastatic tumors. The traditional role for percutaneous biopsy of renal masses has been limited, and so there is little general experience. There have been concerns about safety and accuracy. This review provides an update on the current techniques, indications and accuracy of needle biopsy of renal tumors. MATERIALS AND METHODS: PubMed and MEDLINE were searched for English language reports of percutaneous needle core biopsy and fine needle aspiration of renal tumors that were published from 1977 to 2006. RESULTS: With the development of new biopsy techniques and wider experience with percutaneous probe ablation therapies the risk of tumor seeding appears negligible. Significant bleeding is unusual and almost always self-limiting. At centers with expertise needle core biopsy with or without fine needle aspiration appears to provide adequate specimens for an accurate diagnosis in more than 90% of renal masses. CONCLUSIONS: Percutaneous biopsy of renal masses appears to be safe and it carries minimal risk of tumor spread. Urologists should consider increasing the indications for renal biopsy of small renal masses that appear to be renal cell carcinoma, especially in elderly and unfit patients. With more experience and followup preoperative biopsy has the potential to decrease unnecessary treatment since up to a third of small renal masses are now reported to be benign at surgery. Percutaneous biopsy may also allow a better selection of renal tumors for active surveillance and minimally invasive ablative therapies. Finally, there is potential for stratifying initial therapy for metastatic renal cell carcinoma by histological subtype and in the future molecular characteristics.     

Association between renal mass biopsy and upstaging to perinephric fat involvement in a contemporary cohort of patients with clinical T1a renal cell carcinoma

Background

Although tumor tract seeding from renal mass biopsy (RMB) is exceedingly rare, the possibility of tumor capsule violation from RMB leading to perinephric fat invasion has not been quantified. We evaluated the association between RMB and perinephric fat invasion in patients with clinical T1a renal cell carcinoma who underwent partial or radical nephrectomy.

Accuracy and clinical role of fine needle percutaneous biopsy with computerized tomography guidance of small (less than 4.0 cm) renal masses

PURPOSE: We evaluated the accuracy and clinical role of fine needle percutaneous biopsy of solid renal masses 4.0 cm or smaller with helical computerized tomography (CT) guidance. MATERIALS AND METHODS: In 88 consecutive patients (mean age 61 years) 88 biopsies were performed. Median tumor size was 2.8 cm. Tumor biopsy was performed with an 18 gauge needle using helical CT guidance in an outpatient setting. At least 2 whole cores per tumor were obtained. RESULTS: Biopsy material was insufficient for analysis in 3 (3.4%) procedures. Median tumor size of failed biopsies was 3.0 cm. There were 5 (5.6%) biopsies which revealed fibrosis and were considered inconclusive. A benign lesion was found in 14 (15.9%) biopsies. In the 66 biopsies positive for malignancy there were 65 cases of renal cell carcinoma and 1 lymphoma. A total of 62 patients underwent surgery. Biopsy changed tumor management in 42 (47.8%) patients who avoided radical nephrectomy, 13 of whom had a lesion which did not require surgery, 1 with a lymphoma and 28 who were treated with partial nephrectomy. Biopsy accuracy for histopathological tumor type and Fuhrman nuclear grade was 92% and 69.8%, respectively. No substantial morbidity occurred. CONCLUSIONS: Fine needle biopsy of small renal masses could select benign lesions for which observation might be an alternative to surgery. The accuracy of fine needle biopsy in identifying histological tumor type was high. However, biopsy was less accurate in evaluating Furhman grade. Biopsy with helical CT guidance could be a key point in tailored management of small solid renal masses and provide important information to those patients harboring renal masses.     

Comparison of two core biopsy techniques before and after laparoscopic cryoablation of small renal cortical neoplasms

Introduction:

Cryoablation is an acceptable treatment option for small renal cortical neoplasms (RCN). Unlike extirpative interventions, intraoperative needle biopsy is the only pathologic data for ablated tumors. It is imperative that sampled tissue accurately captures pathology. We studied the optimal intraoperative needle core biopsy protocol for small RCN during laparoscopic renal cryoablation (LCA).

Methods:

Patients with RCN<4cm underwent intraoperative biopsy during LCA. Four biopsy cores were taken per tumor, 2 before and 2 after LCA by using both a standard and modified technique. Standard technique: needle biopsy device was deployed after insertion into the renal tissue at a depth of 5mm. Modified technique: needle biopsy device was deployed 1mm outside of the renal tissue. Biopsies were examined and compared with reference standard pathology. Percentage agreement was calculated across biopsy types (standard vs. modified) and time points (pre- vs. postcryoablation). Logistic regression was used to identify factors impacting biopsy accuracy.

Results:

Thirty patients with 33 RCNs underwent LCA. The mean patient age was 69.1±8.0yrs, and mean tumor size was 2.3±0.7cm. No significant bleeding resulted from biopsies. A definitive diagnosis was made in 31/33 RCNs (94.0%). Ten tumors (30.3%) were benign, 21 (63.7%) were malignant, and 2 (6.0%) were nondiagnostic. Biopsy length was significantly longer using the standard vs. modified technique with mean lengths of 9.3mm vs. 7.0mm, respectively (P=.02). Highest agreement was seen in preablation biopsies (90.3%). A significant association with agreement was seen for younger age (P=.05) and larger tumor size (P=.02).

Conclusions:

Younger age and larger tumor size were associated with improved accuracy. Preoperative sampling resulted in superior accuracy and the standard technique resulted in significantly longer cores. Use of preablation standard biopsy technique may result in the most accurate pathologic diagnosis for patients undergoing cryoablation for small RCNs.     

Rationale for percutaneous biopsy and histologic characterisation of renal tumours

Context

The use of percutaneous biopsy of renal tumours has been traditionally reserved for selected cases because of uncertainties regarding its safety, accuracy, and clinical utility. With the adoption of modern biopsy techniques and increasing expertise in interpreting biopsy specimens, renal tumour biopsy today has limited morbidity and allows histologic diagnosis in the majority of cases in centres with expertise.

Objective

To review the current rationale, indications, and outcomes of percutaneous biopsies and histologic characterisation of renal tumours.

Evidence acquisition

We conducted a systematic review of English-language articles on percutaneous biopsies of renal tumours published between January 1999 and December 2011 using the Medline, Embase, and Web of Science databases. One hundred twelve articles were selected with the consensus of all authors and analysed according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) criteria.

Evidence synthesis

In recent years, the increasing incidence of incidental small renal masses (SRMs), the development of conservative and minimally invasive treatments for low-risk renal cell carcinoma (RCC), and the discovery of novel targeted treatments for metastatic disease have provided the rationale for expanding the indications for renal tumour biopsy. Percutaneous biopsy for diagnostic assessment of SRMs can avoid unnecessary surgeries and support treatment decisions, especially in patients at high surgical risk. Biopsies can confirm histologic success after thermal ablation of SRMs and support the selection of the appropriate systemic therapy for metastatic RCC. There is increasing evidence that further diagnostic and prognostic information can be obtained from renal tumour biopsies with the use of immunohistochemistry, cytogenetic and molecular analysis, and high-throughput gene expression profiling.

Conclusions

Percutaneous biopsies have increasing indications and can significantly contribute to clinical management of renal tumours but are still underutilised in clinical practice. Further research is needed to define optimal and standardised patterns of biopsy and improve the accuracy of biopsies to determine tumour histology. Molecular and genetic analysis of biopsy specimens can provide additional information to support patient counselling and treatment decision making.     

Percutaneous biopsy in large,locally advanced or metastatic renal tumors

Introduction

The role of percutaneous biopsy to characterize large, locally advanced and metastatic primary renal tumors has not been well described. The goal of this article is to describe the potential advantages of biopsy for preoperative evaluation of patients with large renal tumors and advanced disease.

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.     

Long-Term Oncologic Outcomes After Radiofrequency Ablation for T1 Renal Cell Carcinoma

Background

Radiofrequency ablation (RFA) of renal cell carcinoma (RCC) is used to obtain local control of small renal masses. However, available long-term oncologic outcomes for RFA of RCC are limited by small numbers, short follow-up, and lack of pathologic diagnoses.

Objective

To assess the oncologic effectiveness of RFA for the treatment of biopsy-proven RCC.

Design, setting, and participants

Exclusion criteria included prior RCC or metastatic RCC, familial syndromes, or T2 RCC. We retrospectively reviewed long-term oncologic outcomes for 185 patients with sporadic T1 RCC. Median follow-up was 6.43 yr (interquartile range [IQR]: 5.3–7.7).

Outcome measurements and statistical analysis

The chi-square test and Wilcoxon rank-sum tests were used to compare proportions and medians, respectively. Disease-specific survival and overall survival (OS) were calculated using Kaplan-Meier analysis, then stratified by tumor stage, and comparisons were made using log-rank analysis. The 5-yr disease-free survival (DFS) and OS rates are reported. A p value <0.05 was considered statistically significant.

Results and limitations

Median tumor size was 3 cm (IQR: 2.1−3.9 cm). Tumor stage was T1a: 143 (77.3%) or T1b: 42 (22.7%). Twenty-four patients (13%) were retreated for residual disease. There were 12 local recurrences (6.5%), 6 recurrences in T1a disease (4.2%) and 6 in T1b disease (14.3%) (p = 0.0196). Median time to recurrence was 2.5 yr. Local salvage RFA was performed in six patients, of whom five remain disease free at 3.8-yr median follow-up. Tumor stage was the only significant predictor of DFS on multivariate analysis. At last follow-up, 164 patients (88.6%) were disease free (T1a: n = 132 [92.3%]; T1b: n = 32 [76.2%]; p = 0.0038). OS was similar regardless of stage (p = 0.06). Five patients developed metachronous renal tumors (2.7%). Four patients developed extrarenal metastases (2.2%), three of whom died of metastatic RCC (1.6%).

Conclusions

In poor surgical candidates, RFA results in durable local control and low risk of recurrence in T1a RCC. Higher stage correlates with a decreased disease-free survival. Long-term surveillance is necessary following RFA. Patient selection based on tumor characteristics, comorbid disease, and life expectancy is of paramount importance.     

Repeat renal biopsy in a girl with tubulointerstitial nephritis and uveitis syndrome

A Japanese girl aged 8 years who presented with a 2-month history of uveitis subsequently developed tubulointerstitial nephritis. A percutaneous renal biopsy revealed massive interstitial mononuclear cell infiltrates consisting of CD4-positive T cells. Despite administration of topical corticosteroids, the ocular symptoms persisted. Systemic corticosteroid therapy dramatically reduced the ocular symptoms and urinary β₂-microglobulin (β 2MG) concentration. However, reducing the prednisolone dosage induced recurrence of uveitis associated with increased levels of urinary β 2MG. The CD4-positive T cell infiltration persisted in the second renal biopsy performed 6 months after the first renal biopsy. These observations suggest that the interstitial cell infiltration persists for a relatively long time in a proportion of patients with tubulointerstitial nephritis and uveitis syndrome (TINU). Although the renal outcome of TINU has been reported to be favorable, prolonged interstitial cell infiltration may affect long-term renal outcome. Selected patients with TINU should be followed with close observation. Received: 7 February 2001 / Revised: 8 June 2001 / Accepted: 27 June 2001     

胰头部肿块术中组织芯活检临床价值

目的 评价胰头部肿块术中组织芯活检的定性诊断价值.方法 对11 年间行胰头部肿块术中组织芯活检245 例患者的结果,结合手术后病理切片,进行比较和分析.结果 全组患者术中组织芯活检诊断结果示:胰头腺癌188 例(76.7%),慢性胰腺炎39 例(15.9%)、胰腺不典型增生8 例(3.3%)、胰腺神经内分泌肿瘤10 例...     

Incidental renal tumours: the frequency of benign lesions and the role of preoperative core biopsy

OBJECTIVE: To determine the incidence of benign renal lesions in incidentally discovered small renal tumours, increasingly detected by the widespread use of abdominal imaging, and to evaluate whether preoperative renal core biopsy is effective in identifying benign lesions. MATERIALS AND METHODS: In a retrospective study, renal core biopsies for incidental tumours over a 5-year period were analysed. The biopsies were correlated with the final pathology of the nephrectomy specimens, or with patient follow-up if nephrectomy was avoided. RESULTS: Of 70 diagnostic core biopsies, a third of cases were considered benign. The sensitivity and specificity for both benign and malignant lesions when compared to definitive pathology was 100% in all cases subjected to nephrectomy. Of the 30 non-diagnostic biopsies, three were proved to be benign, and 18 likely to be benign. The only complication of renal biopsy was one case of bleeding after biopsy. CONCLUSION: A higher than previously anticipated proportion of incidentally detected small renal masses are benign. Given the high sensitivity and specificity, there is value in taking a core biopsy of small incidental renal lesions, a procedure with a low complication rate (1%). When analysed by a pathologist familiar with renal biopsy, this might avoid radical nephrectomy in many patients.     

Approach to the small renal mass: to treat or not to treat

Accurately conveying the benefits and risks of treatment interventions to patients diagnosed with small renal masses (SRMs) is essential to appropriately identify which patients will achieve better oncologic outcomes and confer a survival advantage from primary therapy. Treatment decisions to determine the ideal management with nephrectomy, thermal ablation, or active surveillance for patients diagnosed with an SRM remain highly complex. Existing prediction tools that incorporate various key clinical variables may facilitate an informed decision about the best management of SRM by more appropriately selecting treatment individualized to the characteristics of the SRM and the patient's clinical characteristics.