The management of nephroblastoma with cavo-atrial disease at presentation: experience from a developing country

Wilms Tumor with Vena Caval Intravascular Extension: A Surgical Perspective

Wilms tumor (WT) is the most common kidney tumor in pediatric patients. Intravascular extension of WT above the level of the renal veins is a rare manifestation that complicates surgical management. Patients with intravascular extension are frequently asymptomatic at diagnosis, and tumor thrombus extension is usually diagnosed by imaging. Neoadjuvant chemotherapy is indicated for thrombus extension above the level of the hepatic veins and often leads to thrombus regression, obviating the need for cardiopulmonary bypass in cases of cardiac thrombus at diagnosis. In cases of tumor extension to the retrohepatic cava, neoadjuvant therapy is not strictly indicated, but it may facilitate the regression of tumor thrombi, making resection safer. Hepatic vascular isolation and cardiopulmonary bypass increase the risk of bleeding and other complications when utilized for tumor thrombectomy. Fortunately, WT patients with vena caval with or with intracardiac extension have similar overall and event-free survival when compared to patients with WT without intravascular extension when thrombectomy is successfully performed. Still, patients with metastatic disease at presentation or unfavorable histology suffer relatively poor outcomes. Dedicated pediatric surgical oncology and pediatric cardiothoracic surgery teams, in conjunction with multimodal therapy directed by a multidisciplinary team, are preferred for optimized outcomes in this patient population.

Breaking down tumor thrombus: Current strategies for medical management

Tumor thrombus, the intravascular extension of tumor into adjacent blood vessels, is frequently encountered in patients with renal cell carcinoma and hepatocellular carcinoma, and often involves the abdominal vasculature including the renal vein, portal vein, and the inferior vena cava. While a bland thrombus is composed of platelets and fibrin, in contrast, a tumor thrombus refers to an organized collection of tumor cells. Though oftentimes detected incidentally on imaging, tumor thrombus may have significant clinical implications and can be challenging to differentiate from bland thrombus. Additionally, the optimal management of tumor thrombus, including the use of anticoagulation, remains poorly described. This review summarizes common causes of tumor thrombus, as well as its impact on staging, prognosis, and treatment.

Vena Cava Thrombus in Patients with Wilms Tumor

(1) Background: Vena cava thrombus (VCT) is rare in Wilms tumor (WT) (4−10%). The aim of this study is to identify factors for an outcome to improve treatment for better survival. (2) Methods: 148/3015 patients with WT (aged < 18 years) and VCT, prospectively enrolled over a period of 32 years (1989−2020) by the German Society for Pediatric Oncology and Hematology (SIOP-9/GPOH, SIOP-93-01/GPOH and SIOP-2001/GPOH), are retrospectively analyzed to describe clinical features, response to preoperative chemotherapy (PC) (142 patients) and surgical interventions and to evaluate risk factors for overall survival (OS). (3) Results: 14 VCT regressed completely with PC and another 12 in parts. The thrombus was completely removed in 111 (85.4%), incompletely in 16 (12.3%), and not removed in 3 (2.3%). The type of removal is unknown in four patients. Patients without VCT have a significantly (p < 0.001) better OS (97.8%) than those with VCT (90.1%). OS after complete resection is (89.9%), after incomplete (93.8%) and with no resection (100%). Patients with anaplasia or stage IV without complete remission (CR) after PC had a significantly worse OS compared to the remaining patients with VCT (77.1% vs. 94.4%; p = 0.002). (4) Conclusions: As a result of our study, two risk factors for poor outcomes in WT patients with VCT emerge: diffuse anaplasia and metastatic disease, especially those with non-CR after PC.

Multidisciplinary Treatment Strategies for Wilms Tumor: Recent Advances, Technical Innovations and Future Directions

Significant progress has been made in the management of Wilms tumor (WT) in recent years, mostly as a result of collaborative efforts and the implementation of protocol-driven, multimodal therapy. This article offers a comprehensive overview of current multidisciplinary treatment strategies for WT, whilst also addressing recent technical innovations including nephron-sparing surgery (NSS) and minimally invasive approaches. In addition, surgical concepts for the treatment of metastatic disease, advances in tumor imaging technology and potentially prognostic biomarkers will be discussed. Current evidence suggests that, in experienced hands and selected cases, laparoscopic radical nephrectomy and laparoscopic-assisted partial nephrectomy for WT may offer the same outcome as the traditional open approach. While NSS is the standard procedure for bilateral WT, NSS has evolved as an alternative technique in patients with smaller unilateral WT and in cases with imminent renal failure. Metastatic disease of the lung or liver that is associated with WT is preferably treated with a three-drug chemotherapy and local radiation therapy. However, surgical sampling of lung nodules may be advisable in persistent nodules before whole lung irradiation is commenced. Several tumor markers such as loss of heterozygosity of chromosomes 1p/16q, 11p15 and gain of function at 1q are associated with an increased risk of recurrence or a decreased risk of overall survival in patients with WT. In summary, complete resection with tumor-free margins remains the primary surgical aim in WT, while NSS and minimally invasive approaches are only suitable in a subset of patients with smaller WT and low-risk disease. In the future, advances in tumor imaging technology may assist the surgeon in defining surgical resection margins and additional biomarkers may emerge as targets for development of new diagnostic tests and potential therapies.

Surgical management, staging, and outcomes of Wilms tumours with intravascular extension: Results of the IMPORT study

PURPOSE

To review surgical management, tumour stage and clinical outcomes in children with intravascular extension of Wilms tumour (WT) registered in a national clinical study (2012-19).

METHODS

WTs with presence/suspicion of tumour thrombus in the renal vein (RV) or beyond on radiology, surgery or pathology case report forms were identified. Only cases where thrombus was confirmed by surgeon and/or reference pathologist were included. Surgical management, disease stage, overall (OS) and event free survival (EFS) were investigated.

RESULTS

69/583 (11.8%) patients met the inclusion criteria. Forty-six (67%) had abdominal stage III due to thrombus-related reasons: 11 had macroscopically incomplete resection, including 8 cases where cavotomy was not performed; 20 had piecemeal complete resection of thrombus; 15 had microscopically positive resection margins at the RV. 66% of tumour thrombi contained viable tumour. There were eight relapses and five deaths. EFS, but not OS, was significantly associated with completeness of surgical resection (P<0.05). OS and EFS were also significantly associated with histological risk group (P<0.05) but not with viability of tumour thrombus (P=0.19; P=0.59).

CONCLUSIONS

WTs with intravascular extension have a high risk of local stage III due to thrombus-related reasons. Controlled complete removal of the thrombus should be the aim of surgery.

LEVEL OF EVIDENCE

Level II.

Impact of neoadjuvant chemotherapy on thrombus viability in patients with Wilms tumour and caval extension: systematic review with meta-analysis

BACKGROUND

Inferior vena cava (IVC) tumour thrombus in children with Wilms tumour is typically managed with neoadjuvant chemotherapy with the intention of achieving thrombus regression in order to minimize the risks associated with complex vascular surgery.

METHODS

A systematic review of Medline and Embase databases was undertaken to identify all eligible studies with reference to thrombus viability in Wilms tumour index cases with caval/cardiac extension. A meta-analysis of proportions was utilized for pooled thrombus viability data across studies. Logistic regression was used to analyse the relationship between thrombus viability and duration of chemotherapy.

RESULTS

Thirty-five eligible observational studies and case reports met inclusion criteria describing a total of 236 patients with thrombus viability data. The pooled proportion of patients with viable tumour thrombus after neoadjuvant chemotherapy was 0.53 (0.43-0.63). Logistic regression analysis of 54 patients receiving either a standard (4-6 weeks) or extended (more than 6 weeks) course of neoadjuvant chemotherapy resulted in an odds ratio of 3.14 (95 per cent c.i. 0.97 to 10.16), P = 0.056, with extended course therapy trending towards viable tumour thrombus.

CONCLUSION

Preoperative chemotherapy is successful in achieving non-viability of caval and cardiac thrombi in around 50 per cent of children, without added benefit from extended cycles of neoadjuvant chemotherapy. Risks versus benefits of extirpative vascular surgery must be considered, therefore, for these high-risk patients.

Intravascular extension of Wilms tumor: Characteristics of tumor thrombus and their impact on outcomes

BACKGROUND

Studies describing intravascular involvement in Wilms tumor have focused on illustrating individual institutional experience and the elements of surgical management. Thrombus characteristics like extent, patterns of regression, and correlation with the surgical findings, intraluminal adhesion, and viable tumor in the thrombus, and patency of the inferior vena cava (IVC) have not been systematically described.

OBJECTIVES

The aim of this study is to evaluate these thrombus characteristics and explore their impact on the overall outcomes.

METHODS

All patients with histologically confirmed Wilms tumors with intravascular thrombus diagnosed in the pediatric oncology unit of Tata Memorial Hospital registered from 2006 to 2019 were included. Data regarding clinical, radiological, and surgical particulars were retrieved from the prospectively maintained institutional database. Specific data for the thrombus included: distal extent before and after neoadjuvant chemotherapy, correlation of extent with the surgical findings, completeness of thrombectomy, the presence of a viable tumor in the thrombus, and the patency of the IVC. Survival analysis was performed utilizing the Kaplan-Meier method on SPSS software version 25.

RESULTS

The study included 43 (9.9%) of the 432 patients with Wilms tumor having intravascular extension. Retrohepatic IVC (33.3%) followed by atrioventricular (26%) formed the frequent levels of thrombus with maximum regression occurring after chemotherapy in the latter (Summary figure). The overall concordance rate between computed tomography (CT) scan and surgical findings for the presence of thrombus was 86% and 4 patients had the thrombus limited to a lower level than the preoperative scan. At a median follow-up of 5-years, the 5-year event-free and overall survival was 81% and 82.2% respectively. Atrioventricular thrombus (p = 0.003) and postoperative patency of IVC (p = 0.02) were significantly associated with inferior survival, while the extent of regression, thrombus fracture, and viability was not significant.

DISCUSSION

The findings of this study bring forth the characteristics of intravascular tumor thrombus affecting the outcomes which can be validated in future prospective studies. Although the ideal method for radiological assessment of the intravascular thrombus is elusive, CT scan provided adequate information for the presence and level of the intravascular thrombus with reasonable accuracy in this study. Study limitations include small sample size, the limited number of events, and lack of multivariate analysis to rule out confounding factors that could influence the observed findings.

CONCLUSION

Atrioventricular thrombus and occlusion of IVC represent adverse prognostic factors. The extent of regression, fracture, and viability of thrombus did not affect survival in this study.

Management and outcome of pediatric Wilms tumor with malignant inferior Vena cava thrombus: largest cohort of single-center experience

BACKGROUND

Wilms tumor (WT) with an inferior Vena cava (IVC) malignant thrombus comprises 4-10% of all WT cases.

METHODS

This retrospective analysis included 51 pediatric patients presenting at Children Cancer Hospital Egypt-57357 from July 2007 to December 2016 with the diagnosis of WT with malignant IVC thrombus.

RESULTS

Median age at presentation = 4.4 years and 28 cases (55%) were females. Twenty-five patients (49%) were metastatic and 4 patients (7.8%) had bilateral disease. Forty-seven cases (92.2%) had favorable histology with no evidence of anaplasia. Level of thrombus extension at presentation was classified as infra-hepatic, retro-hepatic, supra-hepatic and intra-cardiac in 33, 9, 6 and 3 patients, respectively. Fifty patients started neoadjuvant chemotherapy (CTH) with 16 patients showing complete resolution of thrombus after 6 weeks of CTH. None of the patients developed thrombus progression after neoadjuvant CTH; one patient had stationary intra-cardiac thrombus, while remaining patients showed partial regression of their thrombus and had nephrectomy with en-bloc thrombectomy. The mean cranio-caudal dimension of IVC thrombi at initial presentation was 6.5 cm, and 3.6 cm post 6th week of CTH. The 5-year OS and EFS were 75.9% and 71.1%, respectively. There was no significant correlation of initial levels of thrombus extension with survival.

CONCLUSION

Neoadjuvant chemotherapy followed by radical nephrectomy with en-bloc thrombectomy and radiotherapy seems a successful approach for management of patients with WT and IVC tumor thrombus. Measurement of the cranio-caudal dimension of thrombus and its response to treatment should be considered in the surgical planning.

Optimal neoadjuvant chemotherapy duration in Wilms tumour with intravascular thrombus: A literature review and evidence from SIOP WT 2001 trial

INTRODUCTION

Preoperative chemotherapy is recommended for children with Wilms tumour with intravascular extension. Extended chemotherapy may improve resectability, but increase tumour adherence to vascular endothelium, precluding complete resection. To evaluate the optimal length of preoperative treatment, we report a two-part review comprising systematic review of the literature and investigation of patients treated in the International Society of Paediatric Oncology (SIOP) WT 2001 trial.

METHODS

Studies were identified using Medline and Embase databases from 1996 to present. English language titles reporting management of intravascular Wilms tumour were analysed. Patients with Wilms tumour and thrombus were identified from the SIOP WT 2001 trial. Overall survival (OS) and event-free survival (EFS), tumour regression, completeness of resection and cavectomy were investigated.

RESULTS

The search retrieved 43 articles documenting 498 children. Note that 72% of the patients received neoadjuvant chemotherapy: 101 received standard course (4-6 weeks, standard course neoadjuvant chemotherapy [StC]) and 62 extended course (> 6 weeks, extended course neoadjuvant chemotherapy [EC]). There was no significant difference between the groups in terms of thrombus regression or completeness of resection. EFS was greater in the StC group (78 vs 54%; P = .04). Of 4511 patients registered in the SIOP WT 2001 trial, 166 had thrombus. Note that 97% of the patients received neoadjuvant chemotherapy: 63 StC and 67 EC. There was no significant difference between the groups with regard to tumour regression, complete resection, or cavectomy. Survival was significantly higher in those receiving StC than EC (OS: 95% vs 82%, P = .025; EFS: 88% vs 72%, P = .047).

CONCLUSION

There is no evidence that prolonged courses of neoadjuvant chemotherapy beyond the recommended protocols confer any additional benefit in treating intravascular extension of Wilms tumour.

Wilms tumor with dilated cardiomyopathy: A case report

BACKGROUND

Wilms tumor is the most common renal malignancy in childhood. It occurs primarily between the ages of 2 and 5 years. The usual manifestations are abdominal mass, hypertension, and hematuria. The case presented here had an unusual presentation, with dilated cardiomyopathy and hypertension secondary to the Wilms tumor.

CASE SUMMARY

A 3-year-old boy presented with a 5-d history of irritability, poor appetite, and respiratory distress. His presenting clinical symptoms were dyspnea, tachycardia, hypertension, and a palpable abdominal mass at the left upper quadrant. His troponin T and pro-B-type natriuretic peptide levels were elevated. Echocardiography demonstrated a dilated hypokinetic left ventricle with an ejection fraction of 29%, and a suspected left renal mass. Computed tomography scan revealed a left renal mass and multiple lung nodules. The definitive diagnosis of Wilms tumor was confirmed histologically. The patient was administered neoadjuvant chemotherapy and underwent radical nephrectomy. After surgery, radiotherapy was administered, and the adjuvant chemotherapy was continued. The blood pressure and left ventricular function normalized after the treatments.

CONCLUSION

Abdominal mass, dilated cardiomyopathy and hypertension can indicate Wilms tumor in pediatric patients. Chemotherapy and tumor removal achieve successful treatment.

Adult Wilms tumor with inferior vena cava thrombus and distal deep vein thrombosis - a case report and literature review

BACKGROUND

Adult Wilms tumor (WT, nephroblastoma) is a rare, but well-described renal neoplasm. Although inferior vena cava tumor thrombosis is present in up to 10% of Wilms tumors in childhood, only few cases of this clinical manifestation in adults have been reported. To the best of our knowledge, this is the first case of adult WT infiltrating into inferior vena cava (IVC) with concomitant distal deep vein thrombosis.

CASE PRESENTATION

A 28-year-old male patient with gross hematuria and right flank pain was diagnosed with right kidney tumor penetrating to IVC. Preoperatively, acute distal thrombosis in inferior vena cava and lower extremities veins occurred. Right radical nephrectomy with tumor thrombectomy via cavotomy was performed. In order to prevent pulmonary embolism, IVC was ligated below left renal vein level. Histopathological examination revealed a triphasic nephroblastoma without anaplastic features. Postoperatively, patient was diagnosed with metastatic liver disease, which was treated with two lines of chemotherapy followed by radiotherapy with achievement of complete response.

CONCLUSIONS

Adult WT occurs usually in young patients, under 40 years of age. Neoadjuvant chemotherapy proved to be effective in children, resulting with tumor shrinkage and venous tumor thrombus regression. Therefore, percutaneous biopsy should be always considered in young patients presenting with renal tumor invading venous system. IVC ligation is a safe treatment option in the event of complete inferior vena cava occlusion due to distal thrombosis concomitant to tumor thrombus, provided collateral venous pathways are well-developed.

Inferior vena cava involvement in children with Wilms tumor

OBJECTIVES

Retrospective review of children with WT thrombus involving the IVC.

METHODS

We reviewed the charts of 123 patients with WT diagnosed between January 2006 and December 2015. Patients with caval tumor thrombus were identified, demographic data, radiological images, extent of thrombus, chemo- and radiotherapy, surgical approach, pathology reports and outcomes were analyzed.

RESULTS

IVC involvement was identified in 11 patients (9%). Left-sided tumors were more common (55%). Sensitivity of CT scan in thrombus identification was 64%. Neoadjuvant chemotherapy was the primary mode of treatment with 19% reduction of primary tumor size, thrombus resolution in four and regression in six patients. No thrombus progression was observed. Delayed surgical treatment was either nephro-ureterectomy (nine patients) or partial nephrectomy in patients with bilateral WT (two patients). During surgery, thrombectomy and intimal stripping achieved local control in patients with persistent caval tumor. Cardiopulmonary bypass was not needed in patients with initial atrial involvement (five patients). Despite adherence and invasion of tumor thrombus to IVC wall, only one patient required segmental vein resection. All patients eventually achieved CR, none had local relapse. One patient had lung relapse treated to complete remission. The 3-year EFS is 85.7 ± 13.2% and the 3-year OS is 100%.

CONCLUSION

IVC tumor thrombus in patients with WT was managed successfully using preoperative chemotherapy followed by surgery with minimal aggressive approach. Luminal thrombus removal and intimal stripping supplanted by local radio boost when indicated seem to be adequate tools for local control with documented good overall outcomes.

Long-term physiologic and oncologic outcomes of inferior vena cava thrombosis in pediatric malignant abdominal tumors

BACKGROUND

The long-term physiologic and oncologic outcomes of treatment for inferior vena cava (IVC) thrombosis in children with malignant abdominal tumors are unclear.

METHODS

We conducted a retrospective review of children with malignant IVC tumor thrombosis treated at our institution between January 1996 and December 2011. Extent of tumor thrombus was classified using the Hinman system. Disease stage, management, and oncologic and physiologic outcomes and complications were evaluated.

RESULTS

We identified 15 patients (median age, 4.7 years): 12 with Wilms tumor, 2 with hepatoblastoma, and 1 with adrenocortical carcinoma. Neoadjuvant chemotherapy changed Hinman levels in 2 (13%) patients. IVC thrombus resection was complete in 6 (40%) patients, partial in 7 (47%) patients, and not performed in 1 (6.7%) patient. On follow-up imaging, 8 (53%) patients' IVCs were patent, 6 (40%) had residual thrombus, and 1 (6.7%) was surgically interrupted. Three (20%) patients had perioperative complications, and 2 (13%) experienced transient effects related to IVC occlusion.

CONCLUSIONS

Surgical management of tumor thrombus in the vena cava of children with solid abdominal tumors is challenging. Evidence on which to base strong treatment recommendations is lacking. Few long-term physiologic complications were observed.

Wilms tumor with intravascular tumor thrombus

Wilms tumor (WT) is one of the most common solid tumors in children. It is the second most common extracranial solid tumor after neuroblastoma. WT has a strong tendency to invade blood vessels in the form of tumor thrombus, into the renal veins, and inferior vena cava and even into the right atrium. Extension of tumor thrombus along to the renal vein into the inferior vena cava occurs in 4-10% of all patients. Tumor thrombus extending to the right atrium is less reported as 0.7-1%. WT with renal vein thrombus has been reported to be more common in the right kidney because of the shorter right renal vein. Most patients with tumor thrombus are asymptomatic and diagnosis is only made on imaging investigations. Several imaging modalities including computed tomography (CT), magnetic resonance imaging (MRI) and Doppler ultrasonography (USG) can demonstrate intravascular tumor thrombus before surgery. In addition to CT and MRI, Doppler USG is reliable in demonstrating the presence and extent of inferior vena cava tumor thrombus. The management of WT with tumor thrombus is determined by multiple factors such as extent of tumor thrombus, chemotherapy response of the tumor. Now, it is generally recommended to use preoperative chemotherapy to a patient presenting with intravascular tumor thrombus. This approach is helpful to decrease the extent of the vascular thrombus which facilitates surgical excision. Most intracaval and intraatrial thrombi in WT show a response to chemotherapy. Neoadjuvant chemotherapy causes tumor regression in nearly half of the patients. Most of them can be managed without the need for cardiac bypass surgery. The decision of initial surgery or preoperative chemotherapy should be carefully determined on every case. Primary surgery would only be indicated in a patient who is unstable because of thrombus that might dislodge and cause acute symptoms. Presence of tumor thrombus in WT needs for multidisciplinary care including pediatric oncologists, pediatric surgeons, and pediatric cardiac surgeons.