Surveillance of Small Renal Masses

Factors that Affect Outcome of Ultrasound-Guided Radiofrequency Ablation of Renal Masses

The purpose of this study was to examine the factors influencing the efficacy and safety of the ultrasound-guided radiofrequency ablation of renal tumors. Between January 2010 and December 2018, 159 patients with renal tumors treated with ultrasound-guided percutaneous radiofrequency ablation at our institution were included in this study. Biopsies were performed for histopathological analysis prior to each ablation. Patients underwent computed tomography follow-ups at 3, 6, and 12 months and were subsequently observed on an annual basis. The primary efficacy rate (i.e., residual tumor), local tumor progression, morbidity and mortality, and possible outcome predictors (age, body mass index, gender, tumor size, tumor location, tumor characteristics, ablation temperature, and reported technical problems) were analyzed using binary logistic regression. At the first follow-up, 3 months after ablation, the primary efficacy rate was 79%. Two percent of the tumors showed local tumor progression during the whole follow-up. Tumor proximity to the collecting system and the final temperature in the ablation region were associated with the occurrence of residual tumor (OR = 2.85, p = 0.019 and OR = 4.23, p = 0.006, respectively). A similar trend was shown for tumors larger than 3 cm (p = 0.066). A short distance to the collecting system and the ablation temperature were significantly related to the occurrence of residual tumors after the radiofrequency ablation of small renal masses. The ultrasound guidance used in our study has a lower primary efficacy rate than the computed tomography guidance used in comparable studies.

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.

Searching for prognostic biomarkers for small renal masses in the urinary proteome

Renal cell carcinoma (RCC) is frequently diagnosed incidentally as an early-stage small renal mass (SRM; pT1a, ≤4 cm). Overtreatment of patients with benign or clinically indolent SRMs is increasingly common and has resulted in a recent shift in treatment recommendations. There are currently no available biomarkers that can accurately predict clinical behavior. Therefore, we set out to identify early biomarkers of RCC progression. We employed a quantitative label-free liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) proteomics approach and targeted parallel-reaction monitoring to identify and validate early, noninvasive urinary biomarkers for RCC-SRMs. In total, we evaluated 115 urine samples, including 33 renal oncocytoma (≤4 cm) cases, 30 progressive and 26 nonprogressive clear cell RCC (ccRCC)-SRM cases, in addition to 26 healthy controls. We identified six proteins, which displayed significantly elevated expression in clear cell RCC-SRMs (ccRCC-SRMs) relative to healthy controls. Proteins C12ORF49 and EHD4 showed significantly elevated expression in ccRCC-SRMs compared to renal oncocytoma (≤4 cm). Additionally, proteins EPS8L2, CHMP2A, PDCD6IP, CNDP2 and CEACAM1 displayed significantly elevated expression in progressive relative to nonprogressive ccRCC-SRMs. A two-protein signature (EPS8L2 and CCT6A) showed significant discriminatory ability (areas under the curve: 0.81, 95% CI: 0.70-0.93) in distinguishing progressive from nonprogressive ccRCC-SRMs. Patients (Stage I-IV) with EPS8L2 and CCT6A mRNA alterations showed significantly shorter overall survival (p = 1.407 × 10^-6 ) compared to patients with no alterations. Our in-depth proteomic analysis identified novel biomarkers for early-stage RCC-SRMs. Pretreatment characterization of urinary proteins may provide insight into early RCC progression and could potentially help assign patients to appropriate management strategies.

Patient and provider experiences with active surveillance: A scoping review

Objective

Active surveillance (AS) represents a fundamental shift in managing select cancer patients that initiates treatment only upon disease progression to avoid overtreatment. Given uncertain outcomes, patient engagement could support decision-making about AS. Little is known about how to optimize patient engagement for AS decision-making. This scoping review aimed to characterize research on patient and provider communication about AS, and associated determinants and outcomes.

Methods

MEDLINE, EMBASE, CINAHL, and The Cochrane Library were searched from 2006 to October 2016. English language studies that evaluated cancer patient or provider AS views, experiences or behavioural interventions were eligible. Screening and data extraction were done in duplicate. Summary statistics were used to describe study characteristics and findings.

Results

A total of 2,078 studies were identified, 1,587 were unique, and 1,243 were excluded based on titles/abstracts. Among 344 full-text articles, 73 studies were eligible: 2 ductal carcinoma in situ (DCIS), 4 chronic lymphocytic leukemia (CLL), 6 renal cell carcinoma (RCC) and 61 prostate cancer. The most influential determinant of initiating AS was physician recommendation. Others included higher socioeconomic status, smaller tumor size, comorbid disease, older age, and preference to avoid adverse treatment effects. AS patients desired more information about AS and reassurance about future treatment options, involvement in decision-making and assessment of illness uncertainty and supportive care needs during follow-up. Only three studies of prostate cancer evaluated interventions to improve AS communication or experience.

Conclusions

This study revealed a paucity of research on AS communication for DCIS, RCC and CLL, but generated insight on how to optimize AS discussions in the context of routine care or clinical trials from research on AS for prostate cancer. Further research is needed on AS for patients with DCIS, RCC and CLL, and to evaluate interventions aimed at patients and/or providers to improve AS communication, experience and associated outcomes.

Management of Small Renal Masses

With the ubiquitous use of cross-sectional abdominal imaging in recent years, the incidence of small renal masses (SRMs) has increased, and the evaluation and management of SRMs have become important clinical issues. Diagnosing a mass in the early stages theoretically allows for high rates of cure but simultaneously risks overtreatment. In the past 20 years, surgical treatment of SRMs has transitioned from radical nephrectomy for all renal tumors, regardless of size, to elective partial nephrectomy whenever technically feasible. Additionally, newer approaches, including renal mass biopsy, active surveillance for select patients, and renal mass ablation, have been increasingly used. In this chapter, we review the current evidence-based papers covering aspects of the diagnosis and management of SRMs.

Differences in Renal Tumor Size Measurements for Computed Tomography Versus Magnetic Resonance Imaging: Implications for Patients on Active Surveillance

PURPOSE

To evaluate and compare the accuracy of computed tomography (CT) and magnetic resonance imaging (MRI) in predicting the final pathologic tumor size of partial nephrectomy specimens.

MATERIALS AND METHODS

We analyzed a multi-institutional database of 807 patients who underwent robotic partial nephrectomy for a cT1a renal mass from 2006 to 2016. Patients who had a solitary tumor with complete data on the baseline imaging modality and the tumor size (baseline and pathologic) (n = 349) were included for analysis. Baseline tumor size evaluated by both imaging modalities, in addition to the difference between the measurements and final pathologic tumor size (cm) measurements, was compared between patients who received a baseline CT (n = 276, 79.1%) and those who received an MRI (n = 73, 20.9%).

RESULTS

There were no statistically significant differences between any baseline characteristics and receipt of a CT versus MRI. In multivariable analysis adjusting for confounders, there was no significant difference in the baseline tumor size between patients receiving an MRI and those receiving a CT (2.3 versus 2.6 cm; β = -0.13; 95% confidence interval [CI] = -0.33 to 0.07; P = .208). Tumor size on imaging was smaller from final pathology by 0.43 cm on average (P = .002). Measurement error for the measured baseline versus actual pathologic tumor size did not significantly differ for patients receiving an MRI versus those receiving a CT (0.38 versus 0.44 cm; β = -0.06; 95% CI = -0.16 to 0.04; P = .232).

CONCLUSION

Baseline renal tumor size measurements were not significantly different for CT scan and MRI. Choice of imaging modality can be based on doctor and patient preference, including cost and exposure to radiation.

Renal cell carcinoma: new insights and challenges for a clinician scientist

There is a growing recognition of the complex interplay between renal cell cancer (RCC), kidney function, mechanical reduction of nephron mass, and systemic agents targeting the cancer. Earlier detection of RCC and rising life expectancy of cancer survivors places a greater emphasis on preservation of renal function after cancer resection and during systemic therapy. Unique adverse effects associated with RCC drugs not only help reveal cancer pathophysiology but also expand our knowledge of normal cell signaling and metabolism. In this review, we outline our current understanding of RCC biology and treatment, their bidirectional relationship with kidney function, and unmet research needs in this field.

External validation of a nomogram including the computed tomography imaging score to predict indolent renal masses

PURPOSE

To assess a nomogram including the computed tomography (CT) score and body mass index (BMI) that was constructed to predict indolent diseases in a cohort of patients with renal masses.

MATERIALS AND METHODS

The data collected from patients undergoing partial nephrectomy (PN) or radical nephrectomy (RN) between January 2012 and September 2016 were analyzed. Two urologic surgeons and a radiologist reviewed the images to determine the CT score. Postoperative pathological assessment was performed to categorize renal masses as either indolent or aggressive. The BMI and CT scores were included in the nomogram to identify the risk of indolent disease. The performance of the novel model was assessed by using discrimination, calibration plots, and decision curve analysis (DCA).

RESULTS

Two hundred and two participants (with 202 masses) who underwent RN or PN were included; 37% of the masses were indolent. The predictive performances of the nomogram revealed areas under the curve of 0.866 for masses of all cases and 0.808 for cT1 masses without visible fat. DCA revealed that the nomogram was moderately clinically useful. The calibration plots showed a reasonable calibration and systematic overestimation of indolent disease based on nomogram predictions.

CONCLUSIONS

The CT score nomogram discriminated well between indolent and aggressive renal masses. The model had a reasonable calibration in our cohort for discriminating indolent from aggressive lesions. Further research to validate and assess the nomogram is required.