Histopathologic analysis of tumor bed and peritumoral pseudocapsule after in vitro tumor enucleation on radical nephrectomy specimen for clinical T1b renal cell carcinoma

The Value of Dual-Energy Computed Tomography-Based Radiomics in the Evaluation of Interstitial Fibers of Clear Cell Renal Carcinoma

OBJECTIVE

We investigated the potential of dual-energy computed tomography (DECT) radiomics in assessing cancer-associated fibroblasts in clear cell renal carcinoma (ccRCC).

METHODS

A retrospective analysis was conducted on 132 patients with ccRCC. The arterial and venous phase iodine-based material decomposition images (IMDIs), virtual non-contrast images, 70 keV, 100 keV, and 150 keV virtual monoenergetic images, and mixed energy images (MEIs) were obtained from the DECT datasets. On the Radcloud platform, radiomics feature extraction, feature selection, and model establishment were performed. Seven radiomics models were established using the support vector machine. The predictive performance was evaluated by utilizing receiver operating characteristic and the area under the curve (AUC) was calculated. Nomograms were constructed.

RESULTS

The combined model demonstrated high efficiency in evaluating pseudocapsule thickness with AUC, specificity, and sensitivity of 0.833, 0.870, and 0.750, respectively in the validation set, surpassing those of other models. The precision, F1-score, and Youden index were also higher for the combined model. For evaluating the number of collagen fibers, the combined model exhibited the highest AUC (0.741) among all models, with a specificity of 0.830 and a sensitivity of 0.330. The AUC in the 150 kv model and IMDI model were slightly lower than those in the combined model (0.728 and 0.710, respectively), with corresponding sensitivity and specificity of 0.560/0.780 and 0.670/0.830. The nomogram exhibited that Rad-score had good prediction efficiency.

CONCLUSION

DECT radiomics features have significant value in evaluating the interstitial fibers of ccRCC. The combined model of IMDI + MEI exhibits superior performance in assessing the thickness of the pseudocapsule, while the combined, 150 keV, and IMDI models demonstrate higher efficacy in evaluating collagen fiber number. Radiomics, combined with imaging features and clinical features, has excellent predictive performance. These findings offer crucial support for the clinical diagnosis, treatment, and prognosis of ccRCC and provide valuable insights into the application of DECT.

Characteristics of peritumoral pseudocapsule in small renal cell carcinoma and its influencing factors

BACKGROUND

The aim of this study was to investigate the peritumoral pseudocapsule (PC) status and identify the factors influencing PC status in small renal cell carcinoma (RCCs).

METHODS

A total of 147 patients with small RCC (≤4 cm) who had undergone tumor enucleation (TE) were assigned into three groups according to PC status: complete PC, PC absence, and PC invasion. Computed tomography (CT) imaging and clinicopathological features were compared among the three groups. Univariate and multivariate analyses were performed to identify factors associated with incomplete PC.

RESULTS

The number of patients with complete PC, PC absence, and PC invasion was 87 (59%), 20 (14%), and 40 (27%), respectively. Compared with the other two groups, tumors with complete PC were most common in clear cell RCC (CCRCC) and showed a hyperenhancement pattern (92%) and clear boundary (63%) on CT scanning images (p < 0.001). PC absence was most common in female patients (50%), whereas PC invasion was more common in male patients (85%) (p = 0.017). The tumor diameter in the PC absence group (2.24 ± 0.93 cm) was shorter compared with that of the complete PC group (2.88 ± 0.76 cm) and PC invasion group (3.16 ± 0.64 cm) (p < 0.001). Univariate and multivariate analysis showed that hypoenhancement pattern, unclear boundary, and non-CCRCC subtype were independent risk factors of incomplete PC.

CONCLUSIONS

Hypoenhancement pattern, unclear boundary, and non-CCRCC subtype were significant predictors of incomplete PC in small RCCs. It remains to be established whether TE is an appropriate procedure for patients with incomplete PC.

Prognostic significance of pseudocapsule status in patients with metastatic renal cell carcinoma treated with tyrosine kinase inhibitors

Background

We sought to determine whether pseudocapsule (PS) features have prognostic implications in patients with metastatic renal cell carcinoma (mRCC).

Methods

We retrospectively reviewed 231 patients diagnosed with mRCC and treated with tyrosine kinase inhibitors; 188 patients with data available regarding the tumor-parenchyma interfacial PS of the primary tumor were enrolled for analysis. PS status was evaluated as intact (grade 0), merely involved (grade 1), penetrated (grade 2), and absent (grade 3). We applied the Kaplan-Meier method and Cox regression model to assess the survival impact.

Results

Of the 188 patients, 19 (10.1%), 61 (32.4%), 96 (51.1%) and 12 (6.4%) had grade 0, 1, 2 and 3 PS, respectively. PS status was significantly associated with histology (P=0.0206), venous tumor embolus (P=0.0511), microvascular invasion (P=0.0108) and microsatellite formation (P=0.0097). Patients without a PS had the worst overall survival (OS), with a 3-year OS rate of 12.7%, whereas the OS rates for grades 0, 1 and 2 were 78.8%, 50.8% and 43.6%, respectively. Adjusted by other variables, grade 3 and grade 2 PS gave rise to a much higher risk of death across the cohort [hazard ratio (HR) =5.217, P=0.0182; HR =3.765, P=0.0281, respectively]. Sarcomatoid change was also an independent factor for OS (HR =2.932, P=0.0075). In contrast, microsatellite formation was not associated with survival in the cohort.

Conclusions

PS status has prognostic implications for OS in metastatic renal cancer. The absence of the PS and sarcomatoid change are two pathological features related to an extremely poor prognosis.

A CT-Based Tumoral and Mini-Peritumoral Radiomics Approach: Differentiate Fat-Poor Angiomyolipoma from Clear Cell Renal Cell Carcinoma

Objective

This study aimed to evaluate the role of tumor and mini-peritumor in the context of CT-based radiomics analysis to differentiate fat-poor angiomyolipoma (fp-AML) from clear cell renal cell carcinoma (ccRCC).

Methods

A total of 58 fp-AMLs and 172 ccRCCs were enrolled. The volume of interest (VOI) was manually delineated in the standardized CT images and radiomics features were automatically calculated with software. After methods of feature selection, the CT-based logistic models including tumoral model (Ra-tumor), mini-peritumoral model (Ra-peritumor), perirenal model (Ra-Pr), perifat model (Ra-Pf), and tumoral+perirenal model (Ra-tumor+Pr) were constructed. The area under curves (AUCs) were calculated by DeLong test to evaluate the efficiency of logistic models.

Results

The AUCs of Ra-peritumor of nephrographic phase (NP) were slightly higher than those of corticomedullary phase (CMP). Furthermore, the Ra-Pr showed significant higher efficiency than the Ra-Pf, and relative more optimal radiomics features were selected in the Ra-Pr than Ra-Pf. The Ra-tumor+Pr combined tumoral and perirenal radiomics analysis was of most significant in distinction compared with Ra-tumor and Ra-peritumor.

Conclusion

The validity of NP to differentiate fp-AML from ccRCC was slightly higher than that of CMP. To the NP analysis, the Ra-Pr was superior to the Ra-Pf in distinction, and the lesions invaded to the perirenal tissue more severely than to the perifat tissue. It is important to the individual therapeutic surgeries according to the different lesion location. The pooled tumoral and perirenal radiomics analysis was the most promising approach in distinguishing fp-AML and ccRCC.

Computed tomography features predicting aggressiveness of malignant parenchymal renal tumors suitable for partial nephrectomy

The aim of this study was to identify and standardize computed tomography (CT) features having a potential role in predicting aggressiveness of malignant parenchymal renal tumors suitable for partial nephrectomy (PN). We performed a non-systematic review of the recent literature to evaluate the potential impact of CT variables proposed by the Society of Abdominal Radiology Disease-Focused Panel on Renal Cell Carcinoma in predicting aggressiveness of newly diagnosed malignant parenchymal renal tumors. The analyzed variables were clinical tumor size, tumor growth rate, enhancement characteristics, amount of cystic component, polar and capsular location, tumor margins and distance between tumor and renal sinus. Unfavorable behavior was defined as: 1) renal cell carcinoma (RCC) with stage ≥pT3; 2) nuclear grade 3 or 4; 3) presence of sarcomatoid de-differentiation; or 4) non-clear cell subtypes with unfavorable prognosis (type 2 papillary RCC, collecting duct or renal medullary carcinoma, unclassified RCC). Beyond clinical tumor size, tumor growth rate, enhancement characteristics, amount of cystic component, tumor margins and distance between tumor and renal sinus are highly relevant features predicting an unfavorable behavior. Moreover, several studies supported the role of necrosis as preoperative predictor of tumor aggressiveness. Peritumoral and intratumoral vasculature as well as capsule status are emerging variables that need to be further evaluated. Tumor size, enhancement characteristics, tumor margins and distance to the renal sinus are highly relevant CT features predicting biological aggressiveness of malignant parenchymal renal tumors. Combination of these parameters might be useful to generate tools to predict the unfavorable behavior of renal tumors suitable for PN.

Multiphoton Microscopic Study of the Renal Cell Carcinoma Pseudocapsule: Implications for Tumour Enucleation

OBJECTIVE

To utilize Multiphoton Microscopy (MPM) as a novel imaging technique to characterize and quantify collagen at the Renal Cell Carcinoma Pseudocapsule, to assess for both intra-tumoral and inter-tumoral variation of collagen characteristics. MPM combines Second Harmonic Generation and Two Photon Excitation Fluorescence to image extracellular matrix architecture.

METHODS

Twenty partial nephrectomy specimen tissues were retrieved, cut into 5-micron sections, mounted on slides and deparaffinized. The pseudocapsules (PCs) were imaged with 2X and 20X objective at selected Regions of Interest. Corresponding clinical information was retrieved. PC thickness was determined. Collagen parameters measured included quantification by the Collagen Area Ratio, and qualitative measurements by the Collagen Fiber Density and Collagen Reticulation Index.

RESULTS

The boundaries between tumor, PC and normal renal parenchyma were distinguished by MPM without need for staining. In the thickest areas of the PC, collagen content and density were quantitatively higher compared to the thinnest areas. Median Collagen Area Ratio was higher in the thickest compared to the thinnest areas of the PC (P = .01). Clear Cell RCC specimens had a consistently higher Collagen Fiber Density in both the thickest and thinnest areas compared to non-Clear Cell RCC specimens (P = .02).

CONCLUSIONS

We demonstrated the ability of MPM to quantify collagen characteristics of PCs without fluorescent labeling. Tumor enucleation for Renal Cell Carcinoma along its PC remains debatable with regards to oncological safety. Even with a complete and intact PC, the PC is not a homogenous structure, and varies in its thickness and its collagen characteristics within, and between tumors.

Comparison of the long-term follow-up and perioperative outcomes of partial nephrectomy and radical nephrectomy for 4 cm to 7 cm renal cell carcinoma: a systematic review and meta-analysis

Background

The efficacy of partial nephrectomy (PN) for T1b renal cell carcinoma (RCC) is controversial. The oncological outcomes, the change in postoperative renal function and the perioperative complications are unclear.

Methods

We searched PUBMED, EMBASE and the Cochrane Central Register for studies from March 1998 to March 2018 for studies comparing PN to radical nephrectomy (RN) for the treatment of T1b RCC. After data extraction and quality assessment, we used RevMan 5.2 to pool the data. Then, we used Stata 12.0 to perform sensitivity analyses and meta-regression. We used the GRADE profiler to evaluate the evidence according to the GRADE approach.

Results

A total of 16 studies involving 33,117 patients were included in our meta-analysis. No significant difference was found in the 5-year overall survival (OS), 10-year OS, 5-year recurrence-free survival (RFS) and 10-year RFS. The 5-year cancer-special survival (CSS) and 10-year CSS were better in RN compared to PN, respectively, at RR = 1.02, P < 0.05 and RR = 1.04, P < 0.05. PN was better than RN in the preservation of renal function (WMD = -9.15, 95% CI: − 10.30 to − 7.99, P < 0.05). The confidence level grading of the evidence was moderate for 5-year OS, 10-year OS, 5-year CSS, 10-year CSS, 5-year RFS, 10-year RFS, tumor recurrence, decline in eGFR, and postoperative complications.

Conclusions

PN may provide comparable outcomes in terms of RFS & OS, and better renal function preservation although CSS was worse.

Electronic supplementary material

The online version of this article (10.1186/s12894-019-0480-6) contains supplementary material, which is available to authorized users.

The feasibility and safety of modified robot-assisted enucleation for highly complex renal tumors: research on a surgical technique

Background

To report the technical feasibility and oncological safety of modified robot-assisted enucleation for highly complex renal tumors using the combined retroperitoneoscopic and transperitoneoscopic accesses.

Methods

The present research is a retrospective analysis of 166 cases of highly complex renal tumors that underwent a partial nephrectomy at a tertiary academic institution between September 2014 and August 2017. Consecutive consented patients were grouped into two cohorts. Seventy-two cases underwent conventional robot-assisted partial nephrectomy (C-RAPN), and 94 cases were treated with modified robot-assisted tumor enucleation (MRATE). The perioperative and oncological outcomes of both groups were reported. Furthermore, pathological examinations of 225 cases of highly complex renal tumors treated with radical nephrectomy were analyzed.

Results

Although preoperative clinical data were similar between the two groups, the perioperative outcomes were distinctly different. Total renal function at postoperative day 1 was better (P<0.001), and the surgical margin width was narrower (P<0.001) in the MRATE group. In addition, the MRATE group presented less blood loss (143.29 and 90.76 mL; P<0.001) and lower 30-d complication rates (4.2% and 16.7%, respectively; P=0.033). Mean ischemia time and operative time was 3 and 14 minutes shorter in the MRATE group, respectively. Finally, histopathological analysis of 225 cases of renal tumors with high surgical complexity provided objective evidence for the feasibility of MRATE.

Conclusions

MRATE technique may offer an efficient and safe method to treat anatomically complex renal masses in referral centers. The long-term outcome of MRATE technique merits further investigation.

The correlation between affected renal function and affected renal residual volume: A retrospective outcome of laparoscopic nephron-sparing partial nephrectomy with segmental renal artery blocking-up for localized renal tumors

Laparoscopic nephron-sparing partial nephrectomy with segmental renal artery blocking (SRPN) has been widely used in the treatment of localized renal tumors. However, the impact of ischemia-reperfusion injury (IRI) during SRPN remains controversial. This study aims to evaluate the correlation between affected renal function and affected renal volume after SRPN for localized renal tumor treatment, explore the effect of IRI on renal function after SRPN.A total of 39 patients who underwent SRPN for localized renal tumor from June 2009 to April 2012 were reviewed. These patients were followed-up for 5 years. The preoperative affected renal glomerular filtration rate (aGFRpre), postoperative affected renal glomerular filtration rate (aGFRpost), preoperative affected renal volume (aVolpre), and postoperative affected renal volume (aVolpost) were collected during the follow-up period. The correlation between aGFRpost/aGFRpre and aVolpost/aVolpre was compared.A total of 33 patients were successfully followed up. After 3, 6, 12, 24, and 60 months, aGFRpost was 34.6 ± 4.6, 34.7 ± 4.8, 34.9 ± 4.4, 35.1 ± 4.4, and 35.2 ± 4.2 mL/min. The correlation coefficients between aGFRpost/aGFRpre and aVolpost/aVolpre were 0.659 (P = .000), 0.667 (P = .000), 0.663 (P = .000), 0.629 (P = .000), and 0.604 (P = .000), respectively. The limitation of this study was the small cohort size.For the localized renal tumor, aGFRpost was associated with aVolpost, but was not associated with intraoperative factors, such as the time of clamping of the affected segmental renal artery. As a part of nephrons, the resected tumor tissue caused the lack of inherent nephrons, resulting in the loss of renal function. More nephrons should be maintained before resecting the tumor completely during SRPN.Trial registration: ChiCTR-RRC-17011418.

Precision medicine in COPD: where are we and where do we need to go?

Chronic obstructive pulmonary disease (COPD) was the fourth leading cause of death worldwide in 2015. Current treatments for patients ease discomfort and help decrease disease progression; however, none improve lung function or change mortality. COPD is heterogeneous in its molecular and clinical presentation, making it difficult to understand disease aetiology and define robust therapeutic strategies. Given the complexity of the disease we propose a precision medicine approach to understanding and better treating COPD. It is possible that multiOMICs can be used as a tool to integrate data from multiple fields. Moreover, analysis of electronic medical records could aid in the treatment of patients and in the predictions of outcomes. The Precision Medicine Initiative created in 2015 has made precision medicine approaches to treat disease a reality; one of these diseases being COPD.