Predictive factors of recurrence after surgery in patients with non-metastatic renal cell carcinoma with venous tumor thrombus (UroCCR-56 Study)

Dealing with malignancy involving the inferior vena cava in the 21st century

INTRODUCTION

Malignancies involving the inferior vena cava (IVC) have historically been considered not amendable to surgery. More recently, involvement of the IVC by neoplastic processes in the kidney, liver or in the retroperitoneum can be managed successfully.

EVIDENCE ACQUISITION

In this systematic review we summarize the current evidence regarding the surgical management of the IVC in cases of involvement in neoplastic processes. Current literature was searched, and studies selected on the base of the PRISMA guidelines. Evidence was synthesized in narrative form due to heterogeneity of studies.

EVIDENCE SYNTHESIS

Renal cell carcinoma accounts for the greatest proportion of studied patients and can be managed with partial or complete vascular exclusion of the IVC, thrombectomy and direct closure or patch repair with good oncological prognosis. Hepatic malignancies or metastases may involve the IVC, and the joint expertise of hepatobiliary and vascular surgeons has developed various strategies, according to the location of tumor and the need to perform a complete vascular exclusion above the hepatic veins. In retroperitoneal lymph node dissection, the IVC can be excised en-block to guarantee better oncological margins. Also, in retroperitoneal sarcomas not arising from the IVC a vascular substitution may be required to improve the overall survival by clearing all the neoplastic cells in the retroperitoneum. Leiomyoma can have a challenging presentation with involvement of the IVC requiring either thrombectomy, partial or complete substitution, with good oncological outcomes.

CONCLUSIONS

A multidisciplinary approach with specialist expertise is required when dealing with IVC involvement in surgical oncology. Multiple techniques and strategies are required to deliver the most efficient care and achieve the best possible overall survival. The main aim of these procedures must be the complete clearance of all neoplastic cells and achievement of a safe margin according to the perioperative treatment strategy.

Prognostic Significance of NLR About NETosis and Lymphocytes Perturbations in Localized Renal Cell Carcinoma With Tumor Thrombus

Background

Non-metastatic renal cell carcinoma (RCC) with tumor thrombus showed a greater tendency for developing metastases after surgery. Early identification of patients with high risk of poor prognosis is especially important to explore adjuvant treatment of improving outcomes. Neutrophil-to-lymphocyte ratio (NLR) was a systemic inflammation marker and outcome predictor in RCC, reflecting the chaos in systemic immune status in cancer as myeloid cell expansion and lymphatic cell suppression. Neutrophil extracellular traps (NET) formation (NETosis) is the process of neutrophils generating an extracellular DNA net-like structure. NETosis in tumor was demonstrated to conduce to the subsequent metastases of tumor. However, the role of NLR for systemic immune status and tumor local immune infiltration, especially for neutrophil-associated NETs, in non-metastatic RCC with thrombus remains unclear.

Patients and Methods

In our clinical cohort, we enrolled the clinical, pathologic, and preoperative laboratory parameters of 214 RCC patients with tumor thrombus who were treated surgically. The clinical endpoint was defined as cancer-specific survival (CSS). In our basic research cohort, RNA-seq, TCR-seq, and scRNA-seq data were analyzed. Patients who reached the endpoint as recurrence-free survival (RFS) were defined as the “High-risk” group. Otherwise, they were separated into the “Low-risk” group.

Results

In the clinical cohort, NLR≥4 was an independent risk factor for 203 localized RCC with tumor thrombus. In the basic research cohort, tumor thrombi were separated into NETosis-thrombi belonging to the “High-risk” group and non-NETosis-thrombi to the “Low-risk” group. NETs induced by tumor-derived G-CSF in tumor thrombus has a mechanistic role in unfavorable prognosis. Besides, NETs-score from single sample GSEA (ssGSEA) algorithm was an independent prognostic factor validated in the TCGA data. Apart from the neutrophils-associated NETosis, systemic immune perturbations of lymphocytes occurred in the “High-risk” group, represented with decreased TCR diversity and increasingly high proportion of CD4-positive effector memory T (Tem) cells, which indirectly represented the state of lymphopenia.

Conclusions

Our findings firstly demonstrated that neutrophils-associated NETosis and systemic lymphocytes perturbations were considered as tumor progression in patients of localized RCC with tumor thrombus, which reflected NLR≥4 as an independent risk factor for patients.