Nephron sparing surgery for renal cell carcinoma up to 7 cm in the context of guideline development: a contribution of healthcare research

Value of Non-Contrast-Enhanced Vessel Wall MR Imaging in Assessing Vascular Invasion of Retroperitoneal Tumors

BACKGROUND

Due to their location and growth patterns, retroperitoneal tumors often involve the surrounding blood vessels. Clinical decisions on a proper treatment depend on the information on this condition. Evaluation of blood vessels using non-contrast-enhanced vessel wall MRI may provide noninvasive assessment of the extent of tumor invasion to assist clinical decision-making.

PURPOSE

To investigate the performance and potential of non-contrast-enhanced vessel wall MRI in evaluating the degree of vessel wall invasion of retroperitoneal tumors.

STUDY TYPE

Prospective.

POPULATION

Thirty-seven participants (mean age: 60.59 ± 11.77 years, 59% male) with retroperitoneal tumors close to vessels based on their diagnostic computer tomography.

FIELD STRENGTH/SEQUENCES

3 T; vessel wall MRI sequences: two-dimensional T2-weighted MultiVane XD turbo spin-echo (2D-T2-MVXD-TSE) and three-dimensional T1-weighted motion sensitized driven equilibrium fat suppression turbo spin-echo (3D-T1-MSDE-TSE) sequences; conventional MRI sequences: T2-weighted fat suppression turbo spin-echo (T2-FS-TSE), T2-weighted turbo spin-echo (T2-TSE), modified Dixon T1-weighted fast field echo (T1-mDixon-FFE), and diffusion-weighted echo planar imaging (DWI-EPI) sequences.

ASSESSMENT

All patients underwent preoperative imaging using both non-contrast conventional and vessel wall MRI sequences. Images obtained from conventional and vessel wall MRI sequences were evaluated independently by three junior radiologists (3 and 2 years of experience in reading MRI) and reviewed by one senior radiologist (25 years of experience in reading MRI) to assess the degree of vessel wall invasion. MRI were validated results from the clinical standard diagnosis based on surgical confirmation or histopathological reports. Interobserver agreement was determined based on the reports from three readers with similar years of experiences. Intraobserver variability was assessed based on categorizing and recategorizing the vessels of 37 patients 1 month apart.

STATISTICAL TESTS

Intra-class correlation efficient (ICC), Chi-square test, McNemar test, area under the receiver-operating characteristic curve (AUC), Delong test, P < 0.05 was considered significant.

RESULTS

The accuracy of vessel wall MRI (91.96%, 95% CI: 85.43-95.71; 103 of 112) in detecting the degree of vessel wall invasion was significantly higher than that of conventional MRI (75%, 95% CI: 66.24-82.10; 84 of 112). The interobserver variability or reproducibility in categorization of the degree of vascular wall invasion was good in evaluating images from conventional and vessel wall MRI sequences (ICC = 0.821, 95% CI: 0.765-0.867 and ICC = 0.881, 95% CI: 0.842-0.913, respectively).

DATA CONCLUSION

Diagnosis of vessel wall invasion of retroperitoneal tumors and assessment of its severity can be improved by using non-contrast-enhanced vessel wall MRI.

EVIDENCE LEVEL

1 TECHNICAL EFFICACY: Stage 3.

Evaluation of the safety of retroperitoneal laparoscopic partial nephrectomy by investigating the perioperative indicators

Background

In recent years, open nephron sparing partial nephrectomy (OPN) has been gradually applied and generally accepted. Recent statistical data show that PN not only can safely and effectively preserve the functional nephron, but also has fewer complications, low local recurrence rate and no significant difference in long-term survival rate compared with nephrectomy/radical nephrectomy, which has gradually become a routine treatment for small renal cell carcinoma. Therefore, how to maximize the protection of postoperative residual renal function (RRF) and reduce the risk of CKD while achieving the ideal local and overall tumor control effect is the key to the treatment of renal cancer, and is also the focus of attention of urologists and nephrologists.

Objective

To evaluate the safety of retroperitoneal laparoscopic partial nephrectomy (RLPN) by investigating the perioperative indicators and postoperative follow-up.

Methods

A total of 40 hospitalized patients in our hospital from December 2019 to December 2021 were selected and followed up for a long time. Patients with renal tumors less than 4cm in diameter and exogeneous or partial exogeneity were randomly divided into 2 groups. Patients in retroperitoneal laparoscopic group (n = 20) were treated with nephron sparing partial nephrectomy (0.5-1cm). Twenty patients underwent retroperitoneal laparoscopic radical nephrectomy (LRN).The time of removal of drainage tube, drainage volume, time of feeding activity and postoperative hospital stay were recorded, and the safety of the operation was evaluated.

Results

nephron sparing partial nephrectomy is suitable for patients with localized renal carcinoma or benign tumor <4cm. RLPN can be applied to all indications of open nephron sparing partial nephrectomy (OPN), with good safety, and can preserve residual renal function to the greatest extent. The operative vascular occlusion time was controlled within 40 minutes, and the use of renal function protection measures during the operation was safe and controllable in reducing the prevention of warm ischemic kidney damage, with good safety. The renal tumor capsule with 0.5cm~1cm margin was complete by postoperative pathology. In the process of tumor resection and suture collection system in the RLPN group, we improved the previous operation of "resection before hemostasis" to "resection while hemostasis" and "knot-free suture" technology, which saved the operation time of intracavity suture knotting. Reduced cortical tear caused by vertical pull during knot tying. The combined effect of biological clip and hemostatic gauze can stimulate the granulation proliferation of renal cortical wound and accelerate the repair. With the combination of knot-free suture and renal segment vascular occlusion, hot ischemic kidney damage is reduced. In the RLPN group, there were no complications of urinary fistula and bleeding, and no abnormal changes in renal function during follow-up. The safety of RLPN group is worthy of affirmation.

Conclusion

The perioperative safety and short-term postoperative renal function recovery of RLPN are good, and the overall safety of this operation is worthy of affirmation.

MR-Guided Microwave Ablation in T1 Renal Cell Carcinoma: Initial Results in Clinical Routine

Objective

Percutaneous tumor ablation is usually performed using computed tomography (CT) or ultrasound (US) guidance, although reliable visualization of the target tumor could be challenging. Magnetic resonance- (MR-) guided ablation provides more reliable visualization of the target tumors and allows multiplanar imaging of the treatment process, making it the modality of choice, in particular if lesions are small.

Methods

From March 2016 to January 2018, 32 patients scheduled for percutaneous treatment of T1 RCC underwent MR-guided MWA. Complications were classified according to the Clavien grade. Kaplan–Meier survival estimates were calculated to evaluate progression-free survival (PFS).

Results

Technical success was achieved in all lesions. The mean energy and procedure duration were 61.6 ± 8.7 kJ and 118.2 ± 26.7 min, respectively. The glomerular filtration rate (GFR) dropped rapidly after 1 month of treatment and slowly recovered within three months (P < 0.05). Postoperative pain and fever were the most common adverse events after treatment. Perirenal hematoma, thermal injury of the psoas muscle, and abdominal distension were common complications after MWA, and the incidence rates were 9.4% (3/32), 6.3% (2/32), and 6.3% (2/32), respectively. According to the Clavien grade classification, serious complications include hydrothorax, bowel injury, and renal failure, all of which have a probability of 3.1%. Of note, the three serious complications occurred in one patient. The 1-, 2-, and 3-year PFS rates were 96.9%, 93.8%, and 83.9%, respectively. The mean PFS rates were 33.972 months (95% CI: 33.045, 35.900).

Conclusion

Microwave ablation is feasible under MR guidance and provides effective treatment of RCC in one session.

Trifecta achievement in patients undergoing partial nephrectomy: a systematic review and meta-analysis of predictive factors

PURPOSE

The predictors of trifecta achievement in partial nephrectomy (PN) were poorly inquired and remained a controversial area of discovery. To evaluate predictive factors of trifecta achievement in patients undergoing PN.

MATERIALS AND METHODS

A systematic literature search was performed to identify relevant articles. Only studies focusing on postoperative trifecta achievement and exploring its predictor with multivariable analyses were included. The trifecta achievement was defined as negative surgical margins, warm ischemia time <25 minutes, and no complications. Merged odds ratio (OR) and 95% confidence interval (CI) were used to evaluate the predictive effect.

RESULTS

Thirteen studies with 7066 patients meeting the inclusion criteria were included. The rate of trifecta achievement ranged from 43.3% to 78.6%. Merged results showed that preoperative eGFR (OR: 1.01, 95% CI: 1.00, 1.02, P=0.02), operative time (OR: 0.99, 95% CI: 0.99, 1.00, P=0.02), estimated blood loss (OR: 1.00, 95% CI: 1.00, 1.00, P <0.001), tumor size (OR: 0.70, 95% CI: 0.58, 0.84, P <0.001), medium (OR: 0.39, 95% CI: 0.18, 0.84, P=0.02) and high PADUA score (OR: 0.23, 95% CI: 0.08, 0.64, P=0.005) were independently associated with trifecta achievement. A publication bias was identified for tumor size. Sensitivity analysis confirmed the stability of result for tumor size.

CONCLUSIONS

Larger tumor size, medium and high PADUA score are associated with decreased probability of trifecta achievement. After verifying by further high-quality studies, these variables can be incorporated into tools to predict probability of trifecta achievement during clinical practice.

Risk Factors for Upstaging, Recurrence, and Mortality in Clinical T1-2 Renal Cell Carcinoma Patients Upstaged to pT3a Disease: An International Analysis Utilizing the 8th Edition of the Tumor-Node-Metastasis Staging Criteria

OBJECTIVE

To investigate risk factors for and outcomes in pathological T3a-upstaging in Renal Cell Carcinoma (RCC), as Tumor-Node-Metastasis staging for T3a RCC was recently revised.

METHODS

Multicenter retrospective analysis of patients with clinical T1-T2 RCC, stratified by occurrence of pathologic T3a-upstaging. Primary outcome was recurrence-free survival (RFS). Multivariable analyses (MVA) were conducted for upstaging and recurrence. Kaplan-Meier analysis (KMA) was utilized for RFS and overall survival (OS).

RESULTS

We analyzed 2573 patients (1223 RN/1350 PN). Upstaging occurred in 360 (14.0%). On MVA, higher clinical stage was associated with increasing risk of upstaging [cT1a (referent), odds ratio for cT1b, cT2a, and cT2b was 2.6, 6.5, and 14.1, P < .001]. Higher clinical stage at presentation correlated with increasing risk of recurrence in pT3a-upstaged RCC (cT1a upstaged-pT3a [referent], hazard ratio [HR] for cT1b, cT2a, and cT2b upstaged pT3a was 1.16 [P = .729], 3.02 [P = .013], and 4.5 [P = .003]). Perirenal fat (HR 1.6, P = .038) and renal vein (HR 2.2, P = .006) invasion were associated with increased risk of recurrence; type of surgery was not (P = .157). KMA for RFS and OS in pT3a-upstaged patients demonstrated differences based on initial clinical stage (5-year PFS for cT1a/b, and cT2 upstaged was 84.5%/72.8%, and 44.7%, P < .001; 5-year OS for cT1 and cT2 upstaged was 83.8% and 63.2%, P < .001).

CONCLUSION

Risk of pT3a-upstaging and recurrence in pT3a-upstaged RCC correlates with clinical stage at presentation. Renal vein and perinephric fat invasion were associated with increased risk of recurrence. PN did not increase risk of recurrence and potential of pT3a-upstaging should not deter consideration of PN.