A Real-World, Population-Based Retrospective Analysis of Therapeutic Survival for Recurrent Localized Renal Cell Carcinoma After Nephrectomy

Outcomes of Localized Renal Cell Carcinoma Across Different Races

Introduction: Epidemiological outcomes of renal cell carcinoma (RCC) remain sparse. This study aims to compare preoperative characteristics, surgical outcomes, and oncological outcomes of RCC patients at a urology unit in Singapore.Methods: A retrospective cohort analysis of 137 RCC patients in the National University Hospital of Singapore who had undergone partial nephrectomy between 2009 and 2020 was conducted. χ2 tests (Chi-Square Test, Fisher's Exact Test) and one-way analysis of variance (ANOVA) were used for comparing categorical and continuous variables respectively. Kaplan-Meier estimates were used for survival analysis.Results: In total, 137 patients were identified (Chinese [n=82], Malay [n=19], Indian [n=15], Others [n=21]). Indian patients were diagnosed at an earlier age (52.13±10.52 years, P=0.018). A larger percentage of Malay patients (78.9%, P<0.001) were operated on before 2016, prior to the center's adoption of the robotic surgical technique. More Malay and Indian patients underwent laparoscopic surgery (36.8% and 46.7%, P=0.008), experiencing higher rates of intra-operative conversions compared to the Chinese and other ethnicities (5.3% and 13.3% vs. 0%, P=0.011). They also had longer post-operative stays compared to Chinese (7.42±6.46 days; 7.40±7.69 days vs. 4.88±2.87 days, P=0.036). Malays were much less likely to undergo robotic partial nephrectomy compared to Chinese patients (OR=0.295, 95% CI=0.102-0.856) and had the highest rate of metastatic recurrence (10.5%, P=0.023).

Current strategies to diagnose and manage of positive surgical margins and local recurrence after partial nephrectomy

Objective

No standard strategy for diagnosis and management of positive surgical margin (PSM) and local recurrence after partial nephrectomy (PN) are reported in literature. This review aims to provide an overview of the current strategies and further perspectives on this patient setting.

Methods

A non-systematic review of the literature was completed. The research included the most updated articles (about the last 10 years).

Results

Techniques for diagnosing PSMs during PN include intraoperative frozen section, imprinting cytology, and other specific tools. No clear evidence is reported about these methods. Regarding PSM management, active surveillance with a combination of imaging and laboratory evaluation is the first option line followed by surgery. Regarding local recurrence management, surgery is the primary curative approach when possible but it may be technically difficult due to anatomy resultant from previous PN. In this scenario, thermal ablation (TA) may have the potential to circumvent these limitations representing a less invasive alternative. Salvage surgery represents a valid option; six studies analyzed the outcomes of nephrectomy on local recurrence after PN with three of these focused on robotic approach. Overall, complication rates of salvage surgery are higher compared to TA but ablation presents a higher recurrence rate up to 25% of cases that can often be managed with repeat ablation.

Conclusion

Controversy still exists surrounding the best strategy for management and diagnosis of patients with PSMs or local recurrence after PN. Active surveillance is likely to be the optimal first-line management option for most patients with PSMs. Ablation and salvage surgery both represent valid options in patients with local recurrence after PN. Conversely, salvage PN and radical nephrectomy have fewer recurrences but are associated with a higher complication rate compared to TA. In this scenario, robotic surgery plays an important role in improving salvage PN and radical nephrectomy outcomes.

Predicting Clear Cell Renal Cell Carcinoma Survival Using Kurtosis of Cytoplasm in the Hematoxylin Channel from Histology Slides

Purpose

Grade-dependent decrease of lipid storage in clear cell renal cell carcinoma (ccRCC) leads to morphology changes in HE sections. This study investigated the role of cytoplasmic features in frozen sections of ccRCC on prognosis using the digital pathology approach.

Methods

We established an automatic pipeline that performed tumor region selection, stain vector normalization, nuclei segmentation, and feature extraction based on the pathologic data from Shanghai General Hospital and The Cancer Genome Atlas database. Extracted features were subjected to survival analysis.

Results

Kurtosis of the cytoplasm in the hematoxylin channel was correlated with progression-free survival (HR 0.10, 95% CI: 0.04–0.24, p=6.52^∗10⁻⁷) and overall survival (HR 0.11, 95% CI: 0.05–0.31, p=1.72^∗10⁻⁵) in ccRCC, which outperformed other texture features in this analysis. Multivariate Cox regression analysis revealed that low kurtosis of cytoplasm in the hematoxylin channel was an independent predictor for a shorter progression-free survival time (p=0.044) and overall survival time (p = 0.01). Kaplan–Meier survival analysis of progression-free survival and overall survival also showed a significantly worse prognosis in patients with low kurtosis of the cytoplasm in the hematoxylin channel (both p < 0.0001). Lower kurtosis of cytoplasm in the hematoxylin channel was associated with higher pathologic grade, less cholesterol ester, and more mitochondrial DNA content.

Conclusion

Kurtosis of the cytoplasm in the hematoxylin channel predicts survival in clear cell renal cell carcinoma.