Management of Pediatric Tumors With Vascular Extension

Surgical Management of Wilms Tumors with Intravenous Extension: A Multicenter Analysis of Clinical Management with Technical Insights

BACKGROUND

About 5% of Wilms tumors present with vascular extension, which sometimes extends to the right atrium. Vascular extension does not affect the prognosis, but impacts the surgical strategy, which is complex and not fully standardized. Our goal is to identify elements of successful surgical management of Wilms tumors with vascular extensions.

PATIENTS AND METHODS

A retrospective study of pediatric Wilms tumors treated at three sites (January 1999-June 2019) was conducted. The inclusion criterion was the presence of a renal vein and vena cava thrombus at diagnosis. Tumor stage, pre and postoperative treatment, preoperative imaging, operative report, pathology, operative complications, and follow-up data were reviewed.

RESULTS

Of the 696 pediatric patients with Wilms tumors, 69 (9.9%) met the inclusion criterion. In total, 24 patients (37.5%) had a right atrial extension and two presented with Budd-Chiari syndrome at diagnosis. Two died at diagnosis owing to pulmonary embolism. All patients received neoadjuvant chemotherapy and thrombus regressed in 35.6% of cases. Overall, 14 patients had persistent intra-atrial thrombus extension (58%) and underwent cardiopulmonary bypass. Most thrombi (72%) were removed intact with nephrectomy. Massive intraoperative bleeding occurred during three procedures. Postoperative renal insufficiency was identified as a risk factor for patient survival (p = 0.01). With a median follow-up of 9 years (range: 0.5-20 years), overall survival was 89% and event-free survival was 78%.

CONCLUSIONS

Neoadjuvant chemotherapy with proper surgical strategy resulted in a survival rate comparable to that of children with Wilms tumors without intravascular extension. Clinicians should be aware that postoperative renal insufficiency is associated with worse survival outcomes.

Current trends and prospects of surgical techniques for hepatoblastoma

Hepatoblastoma, a common extracranial malignant solid tumor in childhood, is often detected at an advanced stage and is difficult to treat surgically. Despite the availability of multiple comprehensive treatments that can be combined with surgery, hepatoblastoma treatment outcomes remain poor. Surgery is the main treatment strategy for hepatoblastoma, but it faces many challenges, including tumor attachment to surrounding tissues, tumor wrapping or invading of vital organs and tissues, the presence of giant or multiple tumors, distant metastasis, the formation of a tumor thrombus, and significant surgical trauma. In this review, we discuss recent research advances and propose potential strategies for overcoming these challenges. Such strategies may improve the rate of hepatoblastoma resection and local control in children, as well as reduce complications and trauma.

Retroperitoneal yolk sac tumour encroaching the liver and adrenal gland with tumour thrombus in cavo-atrial region and hepatic veins

Paediatric germ cell tumours (GCT) are rare tumours and are unique because of varied clinical presentation and locations. Yolk sac tumour is the predominant malignant histology and a serum marker; alpha fetoprotein is used to see treatment response and recurrent disease. It is extremely rare to find a retroperitoneal GCT with tumour thrombus extending up to the cavo-atrial region with involvement of the hepatic veins. We report a case of retroperitoneal yolk sac tumour (RPYST) with extension to the liver and right adrenal gland along with tumour thrombus in the inferior vena cava and in the right and middle hepatic veins. The child was operated after satisfactory response to chemotherapy. Excision of the tumour along with the right adrenal gland and around 5 cm of retro-hepatic caval resection was done. Inferior vena cava resection was tolerated without reconstruction. Currently child is disease-free and symptom-free at 22 months of follow-up with normal serum marker.

Intravascular Tumor Extension and Pulmonary Tumor Embolism in Children With Solid Malignancies: Is There a Role for Inferior Vena Cava Filters?

Intravascular tumor extension is an uncommon complication of solid malignancies that, when present in the inferior vena cava (IVC), can result in fatal pulmonary tumor embolism. Currently, neoadjuvant chemotherapy and surgery are the mainstays of treatment; however, there are no consensus guidelines for management. We describe three cases of pediatric solid malignancies with associated IVC extension and pulmonary tumor embolism. We hypothesize that there is scope for IVC filter placement in such cases to mitigate the risk of fatal pulmonary tumor embolism.

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.