Renal cell carcinoma with inferior vena cava involvement: Prognostic effect of tumor thrombus consistency on cancer specific survival

A Contemporary Clinicopathologic Analysis of Patients With Renal Cell Carcinoma and Vena Cava Involvement

Renal cell carcinoma (RCC) is occasionally associated with vena cava involvement. Despite recent advances in therapeutic modalities, the 5-year survival in this population continues to be poor. Therefore, further studies are required to better characterize this patient population, especially from the clinicopathologic standpoint. A comprehensive review of patients with RCC and vena cava involvement managed at our institution from 2014 to 2022 was performed. Multiple clinicopathologic parameters including follow-up were obtained. A total of 114 patients were identified. The mean patient age was 63 years (range: 30-84 years). The cohort consisted of 78/114 (68%) males and 36/114 (32%) females. The mean primary tumor size (excluding tumor thrombus) was 11 cm. The majority of tumors (104/114, 91%) were unifocal. Tumor stages were categorized as follows: pT3b (51/114, 44%), pT3c (52/114, 46%), and pT4 (11/114, 10%). Most of the tumors were clear cell RCC 89/114 (78%), although other more aggressive RCC subtypes were also present. Most tumors were WHO/ISUP grade 3 (44/114, 39%) or 4 (67/114, 59%) with sarcomatoid differentiation present in 39/67 (58%). Necrosis was present in 94/114 (82%) tumors. Twenty-three of 114 (20%) tumors were categorized as pM1 and the ipsilateral adrenal gland was the most common site of metastasis. Of the 91 patients categorized as pM, not applicable at nephrectomy, 42/91 (46%) subsequently developed metastasis, most frequently to the lung. Of all patients, only 16/114 (14%) had positive vascular margins and 7/114 (6%) had positive soft tissue margins despite having very advanced disease and a subset considered inoperable at other centers.

Intravoxel Incoherent Motion Diffusion-Weighted MR Imaging and Venous Tumor Thrombus Consistency in Renal Cell Carcinoma

BACKGROUND

Venous tumor thrombus (VTT) consistency of renal cell carcinoma (RCC) is an important consideration in nephrectomy plus thrombectomy. However, evaluation of VTT consistency through preoperative MR imaging is lacking.

PURPOSE

To evaluate VTT consistency of RCC through intravoxel incoherent motion-diffusion weighted imaging (IVIM-DWI) derived parameters (Dt , Dp , f, and ADC) and the apparent diffusion coefficient (ADC) value.

STUDY TYPE

Retrospective.

POPULATION

One hundred and nineteen patients (aged 55.8 ± 11.5 years, 85 male) with histologically-proven RCC and VTT who underwent radical resection.

FIELD STRENGTH/SEQUENCES

3.0-T; two-dimensional single-shot diffusion-weighted echo planar imaging sequence at 9 b-values (0-800 s/mm2 ).

ASSESSMENT

IVIM parameters and ADC values of the primary tumor and the VTT were calculated. The VTT consistency (friable vs. solid) was determined through intraoperative findings of two urologists. The accuracy of VTT consistency classification based on the individual IVIM parameters of primary tumors and of VTT, and based on models combining parameters, was assessed. Type of operation, intra-operative blood loss, and operation length were recorded.

STATISTICAL TESTS

Shapiro-Wilk test; Mann-Whitney U test; Student's t-test; Chi-square test; Receiver operating characteristic (ROC) analysis. Statistical significance level was P < 0.05.

RESULTS

Of the enrolled 119 patients, 33 patients (27.7%) had friable VTT. Patients with friable VTT were significantly more likely to experience open surgery, have significantly more intraoperative blood loss, and significantly longer operative duration. The area under the ROC curve (AUC) values of Dt of the primary tumor and VTT in classifying VTT consistency were 0.758 (95% CI 0.671-0.832) and 0.712 (95% CI 0.622-0.792), respectively. The AUC value of the model combining Dp and Dt of VTT was 0.800 (95% CI 0.717-0.868). Furthermore, the AUC of the model combining Dp and Dt of VTT and Dt of the primary tumor was 0.886 (95% CI 0.814-0.937).

CONCLUSION

IVIM-derived parameters had the potential to predict VTT consistency of RCC.

EVIDENCE LEVEL

3 Technical Efficacy: Stage 2.

Venous tumor thrombus consistency: is it a prognostic factor of survival for patients with renal cell carcinoma?

OBJECTIVES

To evaluate whether venous tumor thrombus (VTT) consistency is a risk factor for the patient's prognosis with renal cell carcinoma (RCC).

MATERIALS AND METHODS

A total of 190 RCC patients with VTT, who were treated at Department of Urology, Chinese PLA General Hospital, were retrospectively analyzed in this study. The baseline clinical characteristics, postoperative outcomes, and pathological findings were analyzed. Tumor thrombus was classified as solid and friable based on their respective characteristics. Survival curves were estimated using the Kaplan-Meier survival curve analysis, and univariable and multivariable cox proportional hazard regression models were used.

RESULTS

Among the total 190 patients included in this study, 145 (76.3%) patients had solid VTT, and 45 (23.7%) patients had friable VTT in their renal veins and inferior vena cava (IVC). There were no significant differences in the age, gender, BMI, symptoms, complex diseases, tumor side, tumor size, TNM stage, Mayo stage, tumor grade, sarcomatous differentiation, pelvic invasion, and sinus fat invasion of patients. Solid VTT consistency was more likely to have a capsule as compared to those with friable VTT (P = 0.007). Kaplan-Meier survival curve analysis demonstrated no statistically significant differences in the overall survival (OS) (P = 0.973) and progression-free survival (PFS) (P = 0.667) of patients. Moreover, VTT consistency was not associated with OS (P = 0.706) of PFS (P = 0.504) in multivariate cox regression analysis.

CONCLUSIONS

RCC VTT consistency was not a prognostic risk factor for predicting the OS and PFS of patients.

Oncologic Outcomes and Predictors in Patients with Stage PT3aNxM0 Renal Cell Carcinoma Following Radical Nephrectomy

OBJECTIVE

The objective of this study is to evaluate oncologic outcomes in patients with PT3aNxM0 renal cell carcinoma following radical nephrectomy and also to investigate these outcomes in each specific subgroup of PT3a renal cell carcinoma and to determine predictive factors of recurrence, metastasis, and mortality.

MATERIALS AND METHODS

In this retrospective cohort study, we included 94 patients with stage PT3a renal cell carcinoma who had undergone radical nephrectomy from 2011 to 2016. All patients who had survived had at least 60 months of follow-up. Demographic and clinical data were collected; univariable and multivariable Cox proportional hazards regression analysis was performed to identify predictors of metastasis, recurrence, and cancer-related mortality.

RESULTS

Patients' mean age was 58.07 ± 11.17 years and 62/94 (65.9%) were male. The mean follow-up time was 48.1 ± 25.5 months. Forty-three patients (45.7%) had experienced cancer-related mortality. The mean cancer-specific survival time was 60.94 months and the mean metastasis-free and local recurrence-free survival times were 57.06 and 88.72 months, respectively. Metastasis and local recurrence had occurred in 42 (44.6%) and 4 (4.25%) patients, respectively. After performing multivariate analysis, higher nuclear Fuhrman's grade (P < .001) and simultaneous involvement of the renal vein and perinephric fat (P < .001) were found to be predictive of cancerrelated mortality. Advanced nuclear Fuhrman's grade was the only independent predictor of metastasis (P=.001).

CONCLUSION

Based on our results, advanced nuclear Fuhrman's grade and sarcomatoid change can independently predict mortality in patients with stage PT3aNxM0 renal cell carcinoma. Close monitoring during the follow-up period is recommended in patients with the mentioned risk factors.

Mid-term results of surgical interventions of high-grade vena cava tumor thrombus

Background

This study aims to investigate whether the coexistence of advanced renal cell carcinoma and inferior vena cava tumor thrombus could be treated with a multidisciplinary approach and teamwork and to evaluate early and mid-term results.

Methods

Between January 2017 and December 2020, a total of 33 patients (28 males, 5 females; mean age: 55.8±13.2 years; range, 27 to 76 years) who underwent radical nephrectomy and thrombectomy of the inferior vena cava were retrospectively analyzed. Demographic characteristics of the patients, types of operations, postoperative data, mortality and morbidity rates were recorded.

Results

Of the patients, 12% (n=4) had Stage 2 tumor thrombus, 60.6% (n=20) had Stage 3 tumor thrombus, and 27% (n=9) had Stage 4 tumor thrombus. A total of 55% (n=19) of the patients had right-sided renal cell carcinoma, while 45% (n=14) of them had a left-sided mass. Totally, 66% (n=22) of the patients underwent primary inferior vena cava repair. The thrombectomy procedure and a Dacron® patch was applied with patch plasty in 24% (n=8) of the patients, and Dacron® graft interposition was applied to the inferior vena cava in 9% (n=3) of the patients. The mean follow-up was 20.3±13.0 (range, 2 to 70) months. Deep vein thrombosis was detected in the follow-up of seven (21%) patients, and no pulmonary thromboembolism was observed during the postoperative follow-up period. The mean length of stay in the intensive care unit was 1.39±0.6 (range, 1 to 3) days. The 30-day mortality rate was 3%, due to the loss of one patient from massive pulmonary embolism intraoperatively.

Conclusion

Vascular surgical procedures performed regardless of the stage of the tumor thrombus provide satisfactory mid-term results in patients with advanced renal cell cancer.

Prognostic significance of extent of venous tumor thrombus in patients with non-metastatic renal cell carcinoma: Results from a Canadian multi-institutional collaborative

PURPOSE

The prognostic significance of level of venous tumor thrombus (VTT) extension in patients with non-metastatic renal cell carcinoma (RCC) has been controversial. The aim of this study was to examine the prognostic significance of VTT extent in patients who underwent surgery for non-metastatic RCC.

MATERIALS AND METHODS

The Canadian Kidney Cancer information system database was used to identify patients who underwent surgery for non-metastatic RCC and VTT from January 2011 to December 2019. Association between VTT level and recurrence-free survival (RFS), cancer-specific survival (CSS) and overall survival (OS) was examined. Univariable and multivariable analyses were performed to estimate predictors of survival.

RESULTS

Out of 6,340 patients during the study period, 228 patients (3.6%) had VTT. VTT was level 0 in 84 (37%), level I to II in 112 (49%), and level III to IV in 33 (14%) patients as per the Mayo Clinic classification. Median age was 65.4 years (interquartile range [IQR] 57.6-72.2) and 169 (74.1%) were male. After a median follow-up of 21.2 months, VTT level did not significantly impact the RFS, CSS, or OS. For VTT level 0, I to II, and III to IV, there was no significant difference in estimated 5-year RFS (31%, 23%, and 30.5%; P > 0.05), CSS (70%, 69%, and 55%; P > 0.05) and OS (64%, 66%, and 50%; P > 0.05). Adjusting for known prognostic factors, thrombus level was not associated with risk of recurrence or death.

CONCLUSION

In a large, multi-institutional cohort of patients undergoing surgery for non-metastatic RCC with tumor thrombus, thrombus extent was not independently associated with recurrence or death.

Analysis of Clinicopathological Factors Influencing Survival in Patients with Renal Cell Carcinoma and Venous Tumor Thrombus

This study aimed to define patients with renal cell cancer and coexisting tumor thrombus in order to address concerns regarding survival and prognostic factors after radical surgery. Several prognostic factors for overall survival (OS) were assessed in patients treated surgically at five institutions from 2012 to 2018. Univariate and multivariate analyses were used to determine the independent risk factors of OS. A total of 142 patients were eligible for further analysis (mean age of 64.75 years, 56% males). Most patients presented with clear cell carcinoma (95%). The Mayo stage was predominantly 0–1 (88%). Distant visceral metastases at the time of diagnosis were present in 36 patients (25%), whereas nodal metastases were present in 24 patients (16.9%). During the follow-up period (mean of 32.5 months), the 3-year OS rate reached 68.2%. The majority of patients received no adjuvant treatment (n = 107). In a multivariable model predicting OS, regional lymph node status (p < 0.001), distant metastases (p = 0.009), tumor grade (p = 0.002), duration of hospitalization (p = 0.016), and Clavien–Dindo grade (p = 0.047) were identified as independent prognostic factors. A subgroup of patients with specific clinicopathological factors may benefit most from the radical surgery, including patients without regional lymph node or distant metastases and with low tumor grades, whereas short hospitalization and low Clavien–Dindo grades represent additional independent prognostic factors.

Clinical outcomes of radical surgery in patients with renal carcinoma and associated venous thrombosis: Single-centre experience in a tertiary care institution

BACKGROUND

Renal carcinoma and associated venous thrombosis cause specific perioperative and postoperative challenges. We aimed to evaluate the factors affecting clinical outcomes in patients undergoing radical surgery because of renal carcinoma and associated venous thrombosis.

MATERIALS AND METHODS

Hospital records were retrospectively reviewed to identify patients with renal carcinoma and associated venous thrombosis treated with radical surgery between 2006 and 2019. Preoperative, perioperative, and postoperative findings were analysed to determine the associations between clinical and survival outcomes. Overall and disease-free survival were analysed by the Kaplan-Meier method. Other associated prognostic variables were assessed using univariate and multivariate Cox regression analyses.

RESULTS

Thirty-three patients with renal carcinoma and associated venous thrombosis were enrolled for this study. There were 15 (45.4%) patients with level I, five (15.2%) with level II, eight (24.2%) with level III, and five (15.2%) with level IV venous thrombosis according to the Mayo Clinic classification system. The median follow-up was 35.6 months. In the univariate analysis, increased tumour size was associated with poor overall and disease-free survival. Preoperative clinic M1 disease was associated with poor overall survival. A high Mayo Clinic thrombus level was associated with poor disease-free survival. In the multivariate analysis, only tumour size and clinic M1 disease were independently correlated with poor overall survival. No independent statistically significant association was detected between thrombus level and survival outcomes.

CONCLUSIONS

Although the thrombus level was not associated with overall and disease-free survival, tumour size and clinic M1 disease were found to have an independent prognostic impact on overall survival.

Prognostic role of bland thrombus in patients treated with resection of renal cell carcinoma with inferior vena cava tumor thrombus

OBJECTIVES

To assess the impact of the presence of bland thrombus (BT) on prognosis of patients treated with resection of renal cell carcinoma (RCC) with inferior vena cava tumor thrombus (IVCTT).

MATERIALS AND METHODS

The medical records of a total of 145 consecutive postsurgical RCC patients with level I-IV IVCTT were reviewed from January 2008 to August 2018. Associations of BT with clinicopathological variables were estimated by chi-square test or Student's t-test. Kaplan-Meier method and multivariate Cox proportional hazard model were used. The eighth TNM staging system, "Spiess PE" model, University of California at Los Angeles Integrated Staging System and Stage, Size, Grade, and Necrosis (SSIGN) score were selected to assess whether BT could improve their predictive abilities.

RESULTS

BT was observed in 34 (23.4%) patients and was significantly associated with increased levels of IVCTT (P = 0.004) and invasion of IVC wall (P = 0.030). Multivariable Cox analyses revealed that tumor grade, T stage, M stage, tumor thrombus consistency and BT were independent risk factors for both progression-free survival and overall survival. The concordance indexes ranged from a low of 0.652 in TNM to a high of 0.731 in SSIGN, and integrating BT into each base model led to an increased predictive accuracies of 6.2% for TNM (P = 0.025), 4.0% for "Spiess PE" model (P = 0.069), 2.1% for University of California at Los Angeles Integrated Staging System (P = 0.149) and 1.2% for SSIGN (P = 0.290), respectively.

CONCLUSIONS

Presence of BT was independently associated with survival in postsurgical patients with RCC-IVCTT. Routine consideration of BT as an adjunct to TNM staging system may be suggested.

[Criteria for an improved prognostic stratification in category pT renal carcinoma]

Asymptomatic renal carcinomas are usually small and localized and thus, for the assessment of pT, precise criteria are required, able to identify the initial phases of a local extension and correlate them with current prognostic prospects. Various studies and consensus meetings have defined precisely how to measure tumoral nodules (solid, cystic and multiple). Furthermore, they have distinguished tumoral extension to the renal sinus, which has a worse prognosis, from that to the perirenal adipose tissue. They have also analyzed the clinical significance of invasion of the sinus vessels, the hilar veins and parenchymal vascular retroinvasion. Our aim is to revise and update the criteria of the different pT subcategories and consider those morphological aspects which could be clinically significant and that are not currently included in the TNM classification.

Tumor Thrombus Into the Inferior Vena Cava After Resection of Renal Cell Carcinoma: Recurrence or Tumor Thrombus Left Behind?

OBJECTIVE

To describe a series of 3 cases of renal cell carcinoma that developed a metachronic recurrence in the form of inferior vena cava tumor thrombus after a first attempt of curative intent by means of radical nephrectomy.

METHODS

A complete work-up consisting of total body computed tomography and transesophagic echocardiography was performed in all cases. After extensive counseling a decision for surgical excision was made. We used a transplant-based approach to eliminate every vestige of visible neoplastic tissue including the tumor thrombus in all cases. Three different approaches, including tangential and circumferencial excision of the inferior vena cava with or without caval replacement by prosthetic vascular graft were used for caval management after thrombectomy.

RESULTS

Estimated blood loss ranged between 500 and 2000 cc. Transfusion requirements varied from 1-9 red blood cell packed units. Complete thrombectomy along with excision of all visible neoplastic lesions was achieved in all cases. One of the patients experimented a cardiac arrest on postoperative day 7 without fatal consequences that increased de length of stay (range 7-30 days). No other major complications were registered. None of the patients died in the first 30 days after the procedure.

CONCLUSION

The transplant-based surgical approach to thrombectomy in these cases provides for excellent exposure and vascular control, thus minimizing the complication rate and resulting a safe treatment option for the patient.

Long-term survival and prognostic factors for locally advanced renal cell carcinoma with renal vein tumor thrombus

BACKGROUND

Previous related studies have mainly focused on renal cell carcinoma (RCC) with venous tumor thrombus, specifically inferior vena cava tumor thrombus with renal vein tumor thrombus (RVTT). However, only a few studies have focused on postoperative long-term survival of RCC patients exclusively with RVTT. Our aim was to investigate the independent prognostic factors for locally advanced RCC with RVTT in China.

METHODS

Patients with locally advanced RCC with RVTT were enrolled for the study from January 2000 to December 2015. All patients underwent radical nephrectomy. Survival analysis was estimated using Kaplan-Meier. Univariable and multivariable survival analyses were performed using COX. Patients were divided into high-risk, middle-risk, and low-risk groups based on independent prognostic factors and then analyzed for survival.

RESULTS

One hundred twenty-eight consecutive patients (103 men & 25 women) were enrolled with a median age of 61 years. Thrombi were all graded 0 using the Mayo system, of which 23 were friable. None of the thrombi detached during surgery. 121 patients were successfully followed up, with a median follow-up period of 47 months. Median overall survival was 127 months (95%CI: 101-153). The 5-year and 10-year cancer-specific survival (CSS) rate was 67.9 and 57.0%. 59 patients had recurrence with median time of 40 months. Friable thrombus, paraneoplastic syndrome (PNS), modified Fuhrman grade 3/4 and perirenal fat invasion were independent prognostic factors (p < 0.05). The 5-year CSS for the Low-risk group (no factors) was 100%, Middle-risk group (1-2 factors) was 68.6%, while the High-risk group (3-4 factors) was 0%.

CONCLUSIONS

After radical surgery, RCC patients with RVTT had a relatively fair prognosis except for patients with friable thrombus, PNS, higher modified Fuhrman grade and perirenal fat invasion.

Whi2 signals low leucine availability to halt yeast growth and cell death

Cells are exquisitely tuned to environmental ques. Amino acid availability is rapidly sensed, allowing cells to adjust molecular processes and implement short or long-term metabolic shifts accordingly. How levels of most individual amino acids may be sensed and subsequently signaled to inform cells of their nutrient status is largely unknown. We made the unexpected observation that small changes in the levels of specific amino acids can have a profound effect on yeast cell growth, leading to the identification of yeast Whi2 as a negative regulator of cell growth in low amino acids. Although Whi2 was originally thought to be fungi-specific, Whi2 appears to share a conserved structural domain found in a family of 25 largely uncharacterized human genes encoding the KCTD (potassium channel tetramerization domain) protein family. Insights gained from yeast Whi2 are likely to be revealing about human KCTDs, many of which have been implicated or demonstrated to cause disease when mutated. Here we report new evidence that Whi2 responds to specific amino acids in the medium, particularly low leucine levels. We also discuss the known pathways of amino acid signaling and potential points of regulation by Whi2 in nutrient signaling in yeast and mammals.

Transabdominal two-cavity approach for radical nephrectomy combined with inferior vena cava thrombectomy for malignant thrombus caused by renal cell carcinoma: a case series

BACKGROUND

Advanced renal cell carcinoma in some cases causes malignant intravascular thrombus with the potential for growth into the inferior vena cava or even the right atrium. Renal cell carcinoma is accompanied by malignant intravascular thrombus in up to 10% of cases. We present an overview of three patients diagnosed as having renal cell carcinoma with malignant intravascular thrombus requiring radical nephrectomy combined with inferior vena cava thrombectomy.

CASE PRESENTATION

Three patients diagnosed as having renal cell carcinoma were indicated for renal cell carcinoma combined with inferior vena cava thrombectomy between 2014 and 2017 at our department: a 69-year-old white Caucasian woman, a 74-year-old white Caucasian woman, and a 58-year-old white Caucasian woman. According to the Novick classification of inferior vena cava tumor thrombus, there was one infrahepatic (level II) and two supradiaphragmatic (level IV) malignant intravascular thrombi. The average age of these patients was 67 years (range 58-74 years). All patients underwent radical nephrectomy combined with inferior vena cava thrombectomy through transabdominal approach. In patients with level IV malignant intravascular thrombus, transesophageal echocardiogram was used to guide the placement of the inferior vena cava cross-clamp above the diaphragm. In one patient the pericardium was opened to place a cross-clamp above a tumor just below the right atrium. There were no postoperative mortalities to date with an average follow-up of 23 months (range 2-48 months). To date, no patient has demonstrated recurrent inferior vena cava malignant intravascular thrombus requiring secondary inferior vena cava thrombectomy or any other treatment. A comparison of estimated blood loss and transfusion rate was not significantly different in all three cases.

CONCLUSION

Despite the technical complexity of the procedure, caval thrombectomy combined with radical nephrectomy currently represents the only radical treatment for renal cell carcinoma accompanied by malignant intravascular thrombus with good mid-term oncological outcomes.

A systematic review and meta-analysis of clinicopathologic factors linked to oncologic outcomes for renal cell carcinoma with tumor thrombus treated by radical nephrectomy with thrombectomy

BACKGROUND

There remain discrepancies over the factors that influence oncologic outcomes after radical nephrectomy with thrombectomy (RNTE). To assess significant predictors of oncologic outcomes after RNTE from a systematic review and meta-analysis.

METHODS

A comprehensive search of PubMed, Embase, Cochrane Library and Web of Science was performed to identify eligible studies. The endpoints included cancer-specific survival (CSS), overall survival (OS), and recurrence-free survival (RFS). A formal meta-analysis was performed for studies containing non-metastatic and metastatic tumors. Additionally, a sensitivity analysis including the subgroup of studies containing non-metastatic tumors only was conducted. Cumulative analyses of hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs) were conducted.

RESULTS

Overall, 35 retrospective studies of low to moderate risk of bias including 11,929 patients were included. The results indicated that large tumor size, high Fuhrman grade, tumor necrosis, positive lymph node, and metastasis at surgery were adverse significant predictors for both CSS and OS. Also, IVC tumor thrombus, sarcomatoid differentiation, perinephretic fat invasion, and adrenal gland invasion were associated with poor CSS. In the subset of non-metastatic patients, the significant predictors were clinical symptom, thrombus level, Fuhrman grade and adrenal gland invasion for CSS; thrombus consistency, Fuhrman grade and tumor necrosis for OS; tumor size, Fuhrman grade and perinephretic fat invasion for RFS.

CONCLUSIONS

A meta-analysis of available data identified significant prognostic factors of CSS, OS and RFS that should be systematically evaluated to propose a risk-adapted approach to postoperative patient counseling, risk stratification, and therapy selection.

The loss of BAP1 protein expression predicts poor prognosis in patients with nonmetastatic clear cell renal cell carcinoma with inferior vena cava tumor thrombosis

OBJECTIVES

Renal cell carcinoma (RCC) is characterized by a propensity for extension into the renal vein and inferior vena cava (IVC) and is associated with poor prognosis. BAP1 mutation, which occurs in about 15% of patients with clear cell RCC (ccRCC), also predicts poor prognosis. The aim of this study was to elucidate the association between BAP1 protein expression and clinicopathological outcomes in patients with nonmetastatic ccRCC with an IVC tumor thrombus (IVCTT).

MATERIAL AND METHODS

Thirty-five patients with nonmetastatic ccRCC with an IVCTT who underwent radical nephrectomy and tumor thrombectomy at our institution from 1999 to 2010 were retrospectively evaluated. Immunohistochemical (IHC) analyses were performed for the expression of BAP1 protein, and the associations between the expression of BAP1 and clinical outcomes were assessed. Survival analyses were performed using the Kaplan-Meier method and log-rank test. Multivariate analyses of the associations between disease-free survival (DFS) and clinical variables including BAP1 protein expression, tumor size, Karnofsky performance status (KPS) score, and the extension level of the tumor thrombus were performed using a Cox proportional hazard model.

RESULTS

The median follow-up time was 58.8 months (range: 2-130 months). The median age was 68 years (range: 37-80 years). The median size of the primary tumor was 9.6cm (range: 3.0-15.0cm). The IVCTT extended above and below the diaphragm in 10 (28.6%) and 25 (71.4%) patients, respectively. The KPS score was>80 in 23 patients (65.7%). BAP1 protein expression on IHC was positive in 24 cases (68.8%) and negative in 11 cases (31.2%). The median overall survival in cases with BAP1-negative and -positive tumor on IHC staining were 44.7 and 81.5 months, respectively (P = 0.052). BAP1-negative tumor on IHC staining was associated with a significantly shorter DFS than BAP1-positive tumor (median DFS = 10.0 vs. 26.0 months, respectively; P = 0.011). Multivariate analysis showed that only BAP1-negative tumor on IHC staining was significantly associated with shorter DFS (P = 0.004).

CONCLUSIONS

Patients whose tumors had loss of BAP1 protein expression were significantly associated with poor prognosis in patients with ccRCC with an IVCTT who underwent radical nephrectomy and tumor thrombectomy.

Genomic features of renal cell carcinoma with venous tumor thrombus

A venous tumor thrombus (VTT) is a potentially lethal complication of renal cell carcinoma (RCC) but virtually nothing is known about the underlying natural history. Based on our observation that venous thrombi contain significant numbers of viable tumor cells, we applied multiregion whole exome sequencing to a total of 37 primary tumor and VTT samples including normal tissue specimens from five consecutive patients. Our findings demonstrate mutational heterogeneity between primary tumor and VTT with 106 of 483 genes (22%) harboring functional SNVs and/or indels altered in either primary tumor or thrombus. Reconstruction of the clonal phylogeny showed clustering of tumor samples and VTT samples, respectively, in the majority of tumors. However, no new subclones were detected suggesting that pre-existing subclones of the primary tumor drive VTT formation. Importantly, we found several lines of evidence for “BRCAness” in a subset of tumors. These included mutations in genes that confer “BRCAness”, a mutational signature and an increase of small indels. Re-analysis of SNV calls from the TCGA KIRC-US cohort confirmed a high frequency of the “BRCAness” mutational signature AC3 in clear cell RCC. Our findings warrant further pre-clinical experiments and may lead to novel personalized therapies for RCC patients.

Loss of PD-L1 (SP-142) expression characterizes renal vein tumor thrombus microenvironment in clear cell renal cell carcinoma

Immunotherapy is a promising tool in the treatment of patients with advancer renal cancer, in particular the blockage of immune checkpoint inhibitors. Clear cell renal cell carcinoma is an example of heterogeneous neoplasm and this particular characteristic is responsible of many therapeutic failures so far. Since variations in the local microenvironment across a tumor may conditionate the effect of this new therapy, a deeper knowledge of this issue seems advisable for any treatment success. We have analyzed the PD-L1 (SP142) expression in three different areas in the tumor and in two areas in the renal vein/caval thrombi in 39 advanced clear cell renal cell carcinomas to determine the extent and potential clinical significance of this regional variability. A statistically significant decrease in PD-L1 expression has been detected between the main tumor and its thrombus faction (p < 0.0001). Also, we have observed a high variability in the PD-L1 positivity across the three different areas of the main tumor tested, with only three cases being uniformly positive in all tested areas. In conclusion, PD-L1 expression display a highly variable distribution in clear cell renal cell carcinomas and this particularity should be kept in mind when selecting the tumor samples to be tested for immunotherapy.

Xeno-pericardial patch repair of the inferior vena cava for radical resection of renal cell carcinoma with tumor thrombus

Background and Objectives

For tumor thrombus in the inferior vena cava (IVC) complicated with kidney cancer, we built a surgical team to achieve (1) en bloc tumor resection; (2) xeno‐pericardial patch IVC repair; and (3) minimum organ damages. We reviewed outcome of the case series to verify rationale of this approach.

Methods

A consecutive series of 12 patients having the IVC tumor thrombus by renal cell carcinoma in the last 3 years was enrolled. Minimum kidney ischemia was induced in five cases (Procedure I), whereas liver and kidney ischemia was induced in five cases (Procedure II). Mild hypothermic extracorporeal circulation was used in two cases (Procedure III).

Results

There was no mortality or severe morbidities related to the surgery. Postoperative recovery was most prompt by the Procedure I. Liver and kidney ischemic time was longer in the Procedure III than the Procedure II, whereas organ function was not substantially impaired in either series. The resected IVC margin was free from the cancer in all cases, while local recurrence was not seen in any cases.

Conclusions

En bloc resection with xeno‐pericardial patch repair of the IVC was successfully performed in the tumor thrombus complicated with kidney cancer with minimum organ damage.

[Level IV inferior vena cava tumor thrombus : A rare diagnosis in patients with renal cell carcinoma]

Renal cell carcinoma in combination with a supradiaphragmatic tumor thrombus is a rare tumor entity. Radical surgery including nephrectomy and thrombectomy is still considered standard treatment. The extent of the tumor thrombus should be preoperatively evaluated by MRI and TEE. An interdisciplinary team is important for surgery planning and realization. Despite the known risks of an operation, a longer overall survival is achieved.