Multimodal treatment of advanced renal cancer in 2017

Bioinformatics analysis identifies GLUD1 as a prognostic indicator for clear cell renal cell carcinoma

BACKGROUND

Renal cell carcinoma (RCC) is a common primary tumor of the kidney and is divided into three major subtypes, of which clear cell renal cell carcinoma (ccRCC) has the highest incidence. Glutamate dehydrogenase 1 (GLUD1) encodes glutamate dehydrogenase 1, which catalyzes the oxidative deamination of glutamate.

METHODS

We analyzed TCGA data using R language software and used multiple online databases to explore the relationship of GLUD1 with signaling pathways and drug sensitivity as well as GLUD1 protein expression and methylation.

RESULTS

The results showed that GLUD1 mRNA expression was reduced in tumor tissues and correlated with the progression of ccRCC. Univariate and multivariate Cox analysis showed that GLUD1 could be used as a prognostic marker for ccRCC. GLUD1 expression in ccRCC was associated with immune cells infiltration and multiple classical signaling pathways. In addition, GLUD1 mRNA expression was related to drug sensitivity.

CONCLUSIONS

These findings provide new ideas for finding new prognostic molecular markers and therapeutic targets for ccRCC.

Interleukin 17 and Its Involvement in Renal Cell Carcinoma

Nowadays, molecular and immunological research is essential for the better understanding of tumor cells pathophysiology. The increasing number of neoplasms has been taken under ‘the molecular magnifying glass’ and, therefore, it is possible to discover complex relationships between the cytophysiology and immune system action. An example could be renal cell carcinoma (RCC) which has deep interactions with immune mediators such as Interleukin 17 (IL-17)—an inflammatory cytokine reacting to tissue damage and external pathogens. RCC is one of the most fatal urological cancers because of its often late diagnosis and poor susceptibility to therapies. IL-17 and its relationship with tumors is extremely complex and constitutes a recent topic for numerous studies. What is worth highlighting is IL-17’s dual character in cancer development—it could be pro- as well as anti-tumorigenic. The aim of this review is to summarize the newest data considering multiple connections between IL-17 and RCC.

Cabozantinib beyond progression improves survival in advanced renal cell carcinoma patients: the CABEYOND study (Meet-URO 21)

BACKGROUND

Cabozantinib improves survival in metastatic renal cell carcinoma (mRCC) after prior antiangiogenics. The best treatment at disease progression (PD) is unknown. Being also a AXL/MET inhibitor, involved in acquired resistance, we hypothesized a prolonged tumor growth control in patients continuing cabozantinib despite PD.

RESEARCH DESIGN AND METHODS

This retrospective multicenter study enrolled patients receiving cabozantinib after the first line between 2014 and 2020. We compared patients maintaining cabozantinib after first PD due to clinical benefit and good tolerability with those who changed therapy. The postprogression survival (PPS) of both was our primary endpoint.

RESULTS

We analyzed 89 patients: 45 received cabozantinib beyond PD and 44 switched therapy. 40.4%, 31.5%, and 28.1% of patients received 1, 2, or >2 prior treatment, respectively. 84.3% were intermediate-poor International Metastatic Renal Cell Carcinoma Database risk. Patients continuing cabozantinib showed a higher response rate to cabozantinib before PD (46.7% vs 25%, p = 0.03) and were more heavily pretreated. Continuing cabozantinib showed a significantly longer PPS compared with switching therapy (median PPS 16.9 vs 13.2 months, HR 0.66, 95%CI 0.48-0.92, p = 0.011).

CONCLUSIONS

We observed longer PPS in patients continuing cabozantinib beyond PD, suggesting that this could be an effective option.

The efficacy evaluation of partial nephrectomy with selective renal artery branch occlusion by laparoscopy

BACKGROUND

To investigate the clinical application and effect of laparoscopic partial nephrectomy with renal artery branch occlusion in the treatment of early renal tumors.

METHODS

A retrospective analysis was conducted on the clinical data of 15 cases of renal tumor patients who underwent partial nephrectomy by laparoscopic selective renal artery branch occlusion in our department from January 2017 to January 2018. Nine male patients and 6 female patients were aged 46 to 65 years, with an average age of 54.3 ± 7.2 years. The diameters of tumors were 2.2 to 4.0 cm, with an average of 3.3 ± 0.7 cm. There are 10 tumors locating on the left side and 5 on the right side. Preoperative renal glomerular filtration rate (GFR) were 77.3 to 61.9 mL/min with an average of 47.6 ± 7.5 mL/min. All patients' diseased kidneys underwent renal computer tomography angiography examination before surgery. And the diseased kidney underwent reexamination of renal GFR. The operation time, renal artery branch occlusion time, intraoperative blood loss, postoperative hospital stay, changes of renal function, and complications were evaluated.

RESULTS

All surgery were completed successfully, the surgery time was 136.7 ± 15.2 min, intraoperative renal artery branch occlusion time was 21.3 ± 4.5 min, the intraoperative blood loss was 223.3 ± 69.5 mL, the postoperative hospital stay was 6.5 ± 1.7 days, and the postoperative 1-month GFR was 49.5 ± 6.6 mL/min. There was no significant difference between the renal GFR before and after surgery (P > .05). There was no blood transfusion and transfer open surgery cases. The patients were followed up for 3 to 15 months without complications.

CONCLUSIONS

Partial nephrectomy with selective renal artery branch occlusion by laparoscopy is a safe, feasible, and effective method for the treatment of early renal cancer. It makes good use of the technical advantages of clear operation field and fine operation of laparoscopic surgery, avoids the heat ischemia process of the whole kidney, and can better protect the renal function.

Radical metastasectomy followed by sorafenib versus observation in patients withclear cell renal cell carcinoma: extended follow -up of efficacy results from the randomized phase II RESORT trial

Background: The RESORT trial showed no longer relapse free survival (RFS) with sorafenib following radical metastasectomy in metastatic renal cell carcinoma. We present the updated 42-month follow-up data.Methods: The phase II RESORT trial randomized patients to sorafenib or observation within 12 weeks from surgery. RFS was the primary endpoint.Results: We analyzed 68 patients (32 in sorafenib and 36 in the observation arm), randomized between November 2012 and November 2017. Eighty-one percent in the sorafenib arm and 80% in the observation arm had one metastasis . At a median follow-up of 42 months (interquartile range 31-58), in the observation arm the median RFS was 35 months, RFS probability was 57% (95% CI 42-76%) at 24 and 44% (95% CI 30-65%) at 48 months. In the sorafenib arm, median RFS was 21 months, RFS probability was 50% (95% CI 34-71%) at 24 and 32% (95% CI 18-57%) at 48 months (p = 0.342;HR 1.35;95% CI 0.72-2.54). Forty-seven percent and 37.5% of the patients in the two arms, respectively, are disease free. The site of relapses was independent of the previous metastasectomy site.Expert commentary: Sorafenib after metastasectomy did not improve RFS, but surgery in selected patients should be considered in order to potentially improve survival.Clinical trial registration: www.clinicaltrials.gov identifier is NCT0144480.

miR-142-5p promotes renal cell tumorigenesis by targeting TFAP2B

The transcription factor AP-2 β (TFAP2B) serves an important role in kidney development. MicroRNAs (miRNAs) regulate carcinogenic pathways and have gained increasing attention owing to their association with human clear cell renal cell carcinoma (ccRCC) tumorigenesis. However, whether miRNAs could affect renal cell tumorigenesis by regulating TFAP2B expression has not been identified. The aim of this study was to investigate the effects of miRNA on TFAP2B and its potential role in cell growth, invasion and migration. PCR, western blot and dual luciferase reporter assays were performed to analyze the effects of miR-142-5p on TFAP2B. Furthermore, MTT, flow cytometry, wound healing and Transwell migration assays were used to analyze the effect of miR-142-5p on cell proliferation and migration. The results demonstrated that miR-142-5p targeted TFAP2B and downregulated the expression of TFAP2B at the mRNA and protein levels, promoting cell proliferation and migration in two ccRCC cell lines, 786-O and A-498. This phenomenon supported the theory that miR-142-5p may function as an oncogene in ccRCC. The potential clinical significance of miR-142-5p as a biomarker and a therapeutic target provides rationale for further investigation into miR-142-5p-mediated molecular pathways and how these may be associated with ccRCC development.

Upregulated circPDK1 Promotes RCC Cell Migration and Invasion by Regulating the miR-377-3P-NOTCH1 Axis in Renal Cell Carcinoma

Background

Circular RNAs (circRNAs) are novel clusters of endogenous noncoding RNAs (ncRNAs) that are involved in the regulation of multiple biological processes in diverse types of cancers. However, the roles and precise mechanisms of circRNAs in renal cell carcinoma (RCC) occurrence and progression have not been clearly elucidated.

Methods

We identified the aberrantly expressed circRNAs in RCC by high-throughput RNA-seq assay and used qRT-PCR to test the expression level of circRNAs in RCC tissues. Loss-of-function experiments were executed to detect the biological roles of circPDK1 in the RCC cells both in vivo and in vitro. RNA Fish, luciferase reporter assays and Western blotting were used to explore the molecular mechanism of circPDK1 function. All data were expressed as the means ± standard error of the mean (SEM). Student’s t-test, one-way ANOVA, Cox regression, an LSD-t-test, Pearson’s chi-squared test, a Log-rank test, and linear regression analyses were used to evaluate the group differences. P < 0.05 was considered significant.

Results

CircPDK1 was overexpressed in RCC tissues and positively associated with patient tumor metastasis and renal cell invasion. The in vivo functional assays also revealed that circPDK1 drove RCC xenograft metastasis. CircPDK1 was mainly located in the cytoplasm, serving as a sponge of miR-377-3P to regulate RCC invasion and metastasis through NOTCH1 (Notch Homolog 1). Ectopic express of NOTCH1 in RCC cell lines will block the metastasis inhibition effect after circPDK1 knockdown.

Conclusion

CircPDK1 is aberrantly expressed in RCC and promotes the metastasis of RCC cells mainly through sponging miR-377-3P and reducing its negative regulation of NOTCH1. Thus, circPDK1 may act as a therapeutic target and biomarker for RCC.

Melatonin as a potential inhibitor of kidney cancer: A survey of the molecular processes

Studies have shown that despite the decreasing mortality rates of kidney cancer patients, its incidence is increasing. Therefore, a comprehensive re-evaluation of treatment options is necessary to provide appropriate treatments for the increasing number of patients. Moreover, the side effects caused by surgery, which is the main treatment of this disease, may lead to higher morbidity rates. Consequently, new safer approaches must be examined and considered. Major advancements have been made in the field of targeted agents as well as treatments based on immunotherapy since renal cell carcinoma (RCC) does not respond well to chemotherapy. While the therapeutic options for this cancer are increasing, the resulting complexity of selecting the best strategy for treating the patients is daunting. Moreover, each therapeutic option must be evaluated concerning toxicity, cost, and clinical advantages. Several characteristics, which are beneficial for cancer therapies have been attributed to melatonin. For decades, investigations have explored the application of melatonin in the treatment of cancer; insufficient attention has been paid to this molecule at the clinical level. Melatonin plays a role in cancer therapy due to its anti-tumor effects as well as by enhancing the efficacy of other drugs as an adjuvant. In this review, we discuss different roles of melatonin in the treatment of kidney cancer. The studies concerned with the applications of melatonin as an adjuvant in the immunotherapy of patients with kidney cancer are summarized. Also, we highlight the apoptotic and anti-angiogenic effects of melatonin on renal cancer cells which are mediated by different molecules (e.g., HIF-1 and VEGF, ADAMTS1, and MMP-9) and signaling pathways (e.g., P56, P52, and JNK). Furthermore, we take a look into available data on melatonin's ability to reduce the toxicities caused by kidney carcinogens, including ochratoxin A, potassium bromate, and Fe-NTA.

Efficacy and safety of apatinib monotherapy in metastatic renal cell carcinoma (mRCC) patients: A single-arm observational study

BACKGROUND

Antiangiogenic treatments play an important role in the therapeutic strategy for metastatic renal cell carcinoma. Apatinib is an oral tyrosine kinase inhibitor that targets vascular endothelial growth factor receptor-2. We aimed to assess the efficacy and safety of apatinib therapy in metastatic renal cell carcinoma patients.

METHODS

Between January 2018 and November 2018, we enrolled 53 metastatic renal cell carcinoma patients. Apatinib was administered at an initial dose of 500 mg once daily. The disease control rate, objective response rate, progression-free survival, and adverse events were reviewed and evaluated.

FINDINGS

Among the 53 patients, 14 achieved partial response and 31 achieved stable disease. Thus, the disease control rate was 84.9% and the objective response rate was 26.4%. The median progression-free survival was 11.2 months (95% confidence interval: 9.884-12.574). Most of the adverse events (AEs) were at grade 1 or 2, and the main grade 3 AEs were hypertension (5.7%), anemia (3.8%), and thrombocytopenia (3.8%).

INTERPRETATION

Apatinib showed promising efficacy and manageable toxicity in metastatic renal cell carcinoma patients, giving potent evidence to conduct further clinical trials.

Predictive Biomarkers of Response to Immunotherapy in Metastatic Renal Cell Cancer

Introduction

In the last decades, the therapeutic decision-making approach to metastatic renal cell cancer (mRCC) has dramatically changed thanks to the introduction in the treatment scenario of, first, anti-angiogenic agents and, afterward, immune-checkpoint inhibitors (ICIs). Immunotherapy is now the standard of care in pretreated mRCC patients and has recently entered even the first line setting. Nevertheless, in mRCC as well as in other tumor settings, a durable and clinically meaningful benefit from treatment with ICIs is not obtained for all patients treated. Therefore, the necessity to identify and validate predictive biomarkers of response to immunotherapy has emerged, in order to design the optimal treatment strategy for mRCC patients.

Discussion

In this review, we present and discuss the most promising predictive biomarkers of response to ICIs in mRCC with the recent data available. In details, the first marker that was investigated is the immunohistochemical expression of programmed death receptor ligand 1 (PD-L1), showing a negative prognostic role in mRCC, but the debate about its potential predictive value is still open. Additionally, the high heterogeneity in PD-L1 determination methods adds complexity to this issue. Second, the tumor mutational or neoantigen burden is an emerging biomarker of increased response to immunotherapy, hypothesizing that the higher the TMB, the higher is the production of neoantigens, and thus the stimulation of anti-tumor immune response, even though controversial results have been obtained. Third, the tumor microenvironment, namely the different populations of the immune infiltrate, plays a key role in tumor progression and in the response to immunotherapy. Finally, several studies have collected evidence on the potential association of the occurrence of immune-related adverse events (irAEs) with the benefit from ICIs, first in non-small cell lung cancer (NSCLC) and melanoma, and recently even in mRCC.

Conclusion

Several promising biomarkers of response to immunotherapy with ICIs have been identified, though without conclusive results upon their potential predictive value in mRCC. Therefore, the results of the exploratory analyses of the recently presented first-line trials and hopefully of future prospective, biomarker-driven studies could provide useful tools to be applied in the everyday clinical practice.

Resveratrol Inhibition of Renal Cancer Stem Cell Characteristics and Modulation of the Sonic Hedgehog Pathway

AIMS

Renal cell cancers typically exhibit high metastasis and recurrence, and this is thought to be due to renal cancer stem cells (CSCs). Meanwhile, aberrant activation of Sonic hedgehog (Shh) signaling is linked with CSCs. Resveratrol has direct or indirect impacts on the pathological activities of CSCs. However, the effects of resveratrol on renal CSCs remain to be elucidated.

METHODS

We cultured renal CSCs in serum-free medium. Western blotting was used to analyze the expression levels of related proteins. The mRNA changes were detected by qRT-PCR after resveratrol treatment. The CD133⁺ cells were quantified by flow cytometry analysis. Immunofluorescence staining images showed the changes in CD44 and Smoothened expression in the cell spheres.

RESULTS

Renal CSCs were enriched by tumorsphere formation assays of ACHN and 786-O cells. Resveratrol treatments markedly decreased the size and number of cell spheres and downregulated the expression of the Shh pathway-related proteins and CSCs markers. Moreover, we observed that resveratrol inhibited cell proliferation and induced cell apoptosis, while purmorphamine upregulated the Shh pathway and weakened the effects of resveratrol on renal CSCs.

CONCLUSIONS

These results suggested that resveratrol is a potential novel therapeutic agent that targets inactivation of renal CSCs by affecting the function of the Shh pathway.

Management of oligometastatic and oligoprogressive renal cell carcinoma: state of the art and future directions

INTRODUCTION

The aim of this paper was to perform a narrative review of the literature on the available approaches in the treatment of two emerging subpopulations of metastatic renal cell carcinoma (mRCC) patients: the oligometastatic disease (less than 5 metastasis) and the oligoprogressive disease, defined as worsening in maximum 3-5 sites while all other tumor sites are controlled by systemic therapy.

AREAS COVERED

We explore all possible approaches in these settings of patients: the role of local therapies, considering both surgical metastasectomy and/or ablative techniques, the efficacy of systemic therapies and the rationale behind active surveillance. We also discuss ongoing clinical trials in these settings.

EXPERT OPINION

Two different strategies are emerging as the most promising for the approach to the oligometastatic/oligoprogressive mRCC patient: (1) the use of immunocheckpoint inhibitors following metastasectomy; (2) the use of stereotactic radiotherapy alone or combined with immunotherapy for oligometastatic disease. The lack of validated biomarkers of response in these mRCC patient subpopulations is opening the way to the employment of novel technologies. Among them, the use of artificial intelligence seems to be the candidate to contribute to precision oncology in patients with mRCC.

Adaptive radiosurgery based on two simultaneous dose prescriptions in the management of large renal cell carcinoma brain metastases in critical areas: Towards customization

Background:

The long-term benefits of local therapy in metastatic renal cell carcinoma (mRCC) have been widely documented. In this context, single fraction gamma knife radiosurgery (SF-GKRS) is routinely used in the management of brain metastases. However, SF-GKRS is not always feasible due to volumetric and regional constraints. We intend to illustrate how a dose-volume adaptive hypofractionated GKRS technique based on two concurrent dose prescriptions termed rapid rescue radiosurgery (RRR) can be utilized in this particular scenario.

Case Description:

A 56-year-old man presented with left-sided hemiparesis; the imaging showed a 13.1 cc brain metastasis in the right central sulcus (Met 1). Further investigation confirmed the histology to be a metastatic clear cell RCC. Met 1 was treated with upfront RRR. Follow-up magnetic resonance imaging (MRI) at 10 months showed further volume regression of Met 1; however, concurrently, a new 17.3 cc lesion was reported in the boundaries of the left frontotemporal region (Met 2) as well as a small metastasis (<1 cc) in the left temporal lobe (Met 3). Met 2 and Met 3 underwent RRR and SF-GKRS, respectively.

Results:

Gradual and sustained tumor ablation of Met 1 and Met 2 was demonstrated on a 20 months long follow- up. The patient succumbed to extracranial disease 21 months after the treatment of Met 1 without evidence of neurological impairment post-RRR.

Conclusion:

Despite poor prognosis and precluding clinical factors (failing systemic treatment, eloquent location, and radioresistant histology), RRR provided optimal tumor ablation and salvage of neurofunction with limited toxicity throughout follow-up.

Outcomes of Multi-disciplinary Management of Metastatic Renal Cell Carcinoma

Metastatic renal cell carcinoma (mRCC) is associated with a poor prognosis. It is traditionally a treatment-resistant disease necessitating multi-modal treatment and close follow-up. We herein report a case of mRCC in a patient who was managed closely by a multi-disciplinary team and still retained a very good performance status and treatment response three years after diagnosis. We highlight the importance of close monitoring, switching systemic therapies at progression, early palliative radiotherapy, and patient education in controlling disease burden and maintaining quality of life in patients with mRCC.

miR-26 suppresses renal cell cancer via down-regulating coronin-3

Coronin-3 (coronin-1C), a homotrimer F-actin-binding protein, has been reported to be important for metastasis in several types of cancers such as lung cancer, gastric cancer, and breast cancer. Here, we present an investigation of the expression and function of coronin-3 in renal cell cancer for the first time. We also confirmed that miR-26 directly targets coronin-3 and down-regulates its expression by western blot assay and dual-luciferase reporter system. The results of MTT and colony formation assay showed that miR-26 suppressed cell proliferation. Wound healing and transwell assay revealed that miR-26 inhibited migration and invasion of renal cancer cell. Moreover, overexpression of coronin-3 could reverse the miR-26-induced inhibition in cell growth and metastasis. Thus, our study suggests that coronin-3 should serve as a potential therapeutic target in renal cell cancer and provide a candidate for miRNA therapy.

Sorafenib Versus Observation Following Radical Metastasectomy for Clear-cell Renal Cell Carcinoma: Results from the Phase 2 Randomized Open-label RESORT Study

BACKGROUND

In selected metastatic renal cell carcinoma (mRCC) patients, radical metastasectomy followed by observation is a potential strategy. It is still to be defined whether systemic therapy should be administered following metastasectomy.

OBJECTIVE

To assess the potential benefit of postoperative treatment with sorafenib compared with observation alone after radical metastasectomy in mRCC patients.

DESIGN, SETTING, AND PARTICIPANTS

The RESORT trial was a multicenter, randomized, open-label, phase 2 study conducted between November 2012 and November 2017 in Italy. Patients with clear-cell mRCC pretreated with nephrectomy and undergoing radical metastasectomy (three or fewer lesions) were eligible for the study. Patients were randomized (1:1) within 12 wk from metastasectomy to sorafenib (standard dose 400 mg twice daily) or observation for a maximum of 52 wk. Stratification factors were interval from nephrectomy, site, and number of lesions. Overall, 76 patients were screened and 69 were randomized: 33 were assigned to sorafenib and 36 to observation. The primary endpoint was recurrence-free survival (RFS). Secondary endpoints were overall survival and the safety profile.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

RFS curves were estimated with the Kaplan-Meier method, and the log-rank test was used to statistically compare the curves.

RESULTS AND LIMITATIONS

At a median follow-up of 38 mo, median RFS was 37 mo (95% confidence interval [CI] 20-not available [NA]) in the observation arm versus 21 mo (95% CI 11-NA) in the sorafenib arm (log-rank test p = 0.404), with 12-, 24-, and 36-mo RFS probability of 74% versus 63%, 59% versus 49%, and 50% versus 41%, respectively, in the observation versus the sorafenib arm. Any-grade adverse event (AE) rates were 84% in the sorafenib arm and 31% in the observation arm; grade ≥3 AE rates were 22% and 3% in the sorafenib and the observation arm, respectively, with a rate of treatment discontinuation for AEs of 19% in the sorafenib arm.

CONCLUSIONS

This prospective study showed that systemic treatment with sorafenib did not increase RFS as compared with observation in mRCC patients following radical metastasectomy.

PATIENT SUMMARY

This article reports the clinical outcome of patients with metastatic renal cell carcinoma treated with sorafenib or managed with an observation-alone strategy after the radical surgery of metastases. We found that sorafenib did not improve the patient outcome in terms of relapse-free survival in this selected population.

The Evaluation of Response to Immunotherapy in Metastatic Renal Cell Carcinoma: Open Challenges in the Clinical Practice

Immunotherapy has changed the therapeutic scenario of metastatic renal cell carcinoma (mRCC), however the evaluation of disease response to immune-checkpoint inhibitors is still an open challenge. Response evaluation criteria in solid tumors (RECIST) 1.1 criteria are the cornerstone of response assessment to anti-neoplastic treatments, but the use of anti-programmed death receptor 1 (PD1) and other immunotherapeutic agents has shown atypical patterns of response such as pseudoprogression. Therefore, immune-modified criteria have been developed in order to more accurately categorize the disease response, even though their use in the everyday clinical practice is still limited. In this review we summarize the available evidence on this topic, with particular focus on the application of immune-modified criteria in the setting of mRCC.

Histologic Diagnosis of Renal Mass Biopsy

CONTEXT.—

Core biopsy has been increasingly used for clinical decision-making in the management of patients with renal masses. The sensitivity and specificity of histologic diagnoses of renal mass biopsies depend on many factors such as adequate sampling and tissue processing, diagnostic skill and experience, and appropriate use of ancillary techniques.

OBJECTIVE.—

To review the indications, emphasize the importance of obtaining adequate diagnostic material, and introduce a general diagnostic approach, in conjunction with immunohistochemistry, in diagnosis of renal mass biopsies.

DATA SOURCES.—

Literature review and personal experiences in daily practice and consultation diagnosis of renal masses in a large tertiary medical center.

CONCLUSIONS.—

For renal mass biopsies, it is critical to obtain adequate diagnostic material and establish a standard laboratory procedure in working with small biopsy specimens. The key for the diagnosis is to be familiar with different tumor entities with characteristic morphology and to understand the wide spectrum of tumor heterogeneity. By developing a systematic approach, one can categorize the tumor and create a sensible differential diagnosis based on the growth pattern and cellular morphology. Immunohistochemistry is particularly helpful for renal mass biopsy diagnosis in selected situations.

Comparisons of percutaneous versus retroperitoneoscopic cryoablation for renal masses

PURPOSE

Preserving renal function and controlling oncological outcomes are pertinent while managing renal tumours. We compared outcomes of percutaneous cryoablation (PCA) and retroperitoneoscopic cryoablation (RCA) in patients with renal neoplasms.

METHODS

We identified 108 patients with renal tumours at two medical centres, where 63 patients received PCA and 45 patients underwent RCA from August 2009 to July 2015, and they were followed up until February 2017. We compared preoperative and postoperative parameters, namely gender, systemic diseases, age, American Society of Anesthesiologists score, body mass index (BMI), haemoglobin, the estimated glomerular filtration rate, tumour size, operative time, tumour type, Clavien-Dindo classification of surgical complications, and tumour recurrence, by using an independent sample t test, Pearson's Chi-square test, Fisher's exact test, a Mann-Whitney test, and a generalised linear model.

RESULTS

Based on baseline characteristics, we found that the patients in the PCA group were older and had higher BMI than those in the RCA group, whereas the patients in the RCA group had more comorbidities than those in the PCA group. Retroperitoneoscopic and percutaneous methods had similar operative times, blood transfusion rates, postoperative fever episodes, and complication rates for either minor or major complications. However, the percutaneous method was associated with a shorter length of stay. No patient experienced deterioration in renal function until 2 years after both procedures. Impaired renal function was found in both groups in the 3-year follow-up. In both groups, tumour recurrence was significant for tumours > 4 cm.

CONCLUSIONS

Our results confirm that both cryoablation methods (PCA and RCA) are safe and effective for renal cell carcinoma. Favourable oncological control was achieved in both groups if the renal tumour size was ≤ 4 cm.