Surgery for the complex Wilms tumour

The rationale for nephron-sparing surgery in unilateral non-syndromic Wilms tumour

The central question of nephron-sparing surgery in unilateral non-syndromic Wilms tumour sits at a crossroads between surgery, oncology, and nephrology. There has been a significant paradigm shift in paediatric oncology towards reducing toxicity and addressing long-term treatment-related sequalae amongst childhood cancer survivors. After paediatric nephrectomy and 30-50 years of follow-up, 40% of patients will have chronic kidney disease, including 22% with hypertension and 23% with albuminuria. It is difficult to predict which patients will progress to develop hypertension, reduced glomerular filtration rate, albuminuria, and a higher cardiovascular risk. For these reasons, nephron-sparing surgery when it is technically feasible must be considered. To decrease the incidence of positive surgical margins (viable tumour present at a resection margin), incomplete lymph node sampling, and complications, these procedures should be performed at specialist and experienced reference centres. Based on the impacts of individual treatment pathways, survivors of childhood WT need to be followed through adulthood for early detection of chronic kidney disease, hypertension, and prevention of cardiovascular events.

Wilms tumor in horseshoe kidney with extensive vascular thrombosis: A case report

INTRODUCTION AND IMPORTANCE

Wilms tumor (WT), a prevalent pediatric renal malignancy (7 %), frequently intertwines with genitourinary anomalies. This unique report presents a case of WT combined with horseshoe Kidney and an extending atrial thrombus, emphasizing critical management considerations.

CASE PRESENTATION

A 3-year-old boy, experiencing flank pain and weight loss, manifested a WT linked to horseshoe Kidney, accompanied by an atrial thrombus. Neoadjuvant chemotherapy downsized the tumor and thrombus, enabling successful surgical intervention. Post-surgery, 27 weeks of adjuvant chemotherapy were administered. Over three years, follow-up exhibited renal recovery, no recurrence, and clear CT scans.

DISCUSSION

Prompt identification, precise imaging (via CT angiography), and multidisciplinary care are pivotal for managing WT in horseshoe Kidney cases. Preoperative chemotherapy notably reduced tumor and thrombus sizes, enhancing surgical feasibility. Long-term vigilance is essential for recurrence and treatment-related complications.

CONCLUSION

Effectively managing WT in horseshoe Kidneys demands timely recognition, meticulous imaging, and collaborative management. Successful outcomes highlight preoperative chemotherapy's benefits and underscore extended monitoring's significance in confirming sustained recovery.

Prechemotherapy Transperitoneal Robotic-Assisted Partial Nephrectomy (RAPN) for a Wilms Tumor: Surgical and Oncological Outcomes in a Four-Year-Old Patient

BACKGROUND

Wilms tumor (WT) is the most frequent renal tumor in children. The SIOP-UMBRELLA Guidelines allow for nephron-sparing surgery (NSS) in syndromic patients, as well as in cases of small (<300 mL) non-syndromic unilateral WTs, without lymph node involvement, and with a substantial expected remnant renal function, following neoadjuvant chemotherapy. We present a case of prechemotherapy transperitoneal robot-assisted partial nephrectomy (RAPN) for a unilateral, non-syndromic Wilms tumor.

METHODS

A four-year-old child presented with a solid mass measuring 3.6 cm in diameter involving the upper right renal pole, incidentally detected during an abdominal echotomography. CT scan and abdominal MRI revealed no local infiltration or lymph node involvement, suggesting that the exophytic mass could be easily resected via an NSS robotic approach. Preoperative imaging did not strongly suggest WT. A virtual 3D reconstruction of the tumor was performed.

RESULTS

After the oncologic board approval, a robot-assisted partial nephrectomy with an intraperitoneal approach was performed. Histopathological analysis confirmed the diagnosis of WT. The patient subsequently received 10 doses of vincristine as adjuvant chemotherapy. A 28-month follow-up showed no tumor recurrence.

CONCLUSIONS

Intraperitoneal RAPN may be an option for selected WT and warrants consideration as a challenging but advantageous approach.

Impact of Time to Surgery on Outcome in Wilms Tumor Treated with Preoperative Chemotherapy

(1) Background: Wilms tumor (WT) treated preoperatively is cured in over 90% of cases. However, how long preoperative chemotherapy can be given is unknown. (2) Methods: 2561/3030 patients with WT (age < 18 years) treated between 1989 and 2022 according to SIOP-9/GPOH, SIOP-93-01/GPOH, and SIOP-2001/GPOH are retrospectively analyzed to assess the risk of time to surgery (TTS) for relapse-free survival (RFS) and overall survival (OS). (3) Results: TTS was calculated for all surgeries, with the mean being 39 days (38.5 ± 12.5) for unilateral tumors (UWT) and 70 days (69.9 ± 32.7) for bilateral disease (BWT). Relapse occurred in 347 patients, of which 63 (2.5%) were local, 199 (7.8%) were metastatic, and 85 (3.3%) were combined. Moreover, 184 patients (7.2%) died, 152 (5.9%) due to tumor progression. In UWT, recurrences and mortality are independent of TTS. For BWT without metastases at diagnosis, the incidence of recurrence is less than 18% up to 120 days and increases to 29% after 120 days, and to 60% after 150 days. The risk of relapse (Hazard Ratio) adjusted for age, local stage, and histological risk group increases to 2.87 after 120 days (CI 1.19-7.95, p = 0.022) and to 4.62 after 150 days (CI 1.17-18.26, p = 0.029). In metastatic BWT, no influence of TTS is detected. (4) Conclusions: The length of preoperative chemotherapy has no negative impact on RFS or OS in UWT. In BWT without metastatic disease, surgery should be performed before day 120, as the risk of recurrence increases significantly thereafter.

Efficacy analysis of multidisciplinary treatment for Wilms tumor in a single center

OBJECTIVE

To analyze the efficacy of multidisciplinary treatment for Wilms tumor (WT) in Kunming Children's Hospital, and investigate the risk factors affecting the prognosis of WT.

METHODS

The clinic-pathological data were collected and analyzed in patients with unilateral WT treated in Kunming Children's Hospital from January 2017 to July 2021. Research subjects were selected according to inclusion criteria and exclusion criteria. The risk factors and independent risk factors that affect the prognosis of patients with WT were determined by Kaplan-Meier survival analysis and Cox proportional hazards model, respectively.

OUTCOME

A total of 68 children were included in this study, and the 5-year overall survival (OS) rate was 87.4%. Kaplan-Meier survival analysis results showed that ethnicity (P = 0.020), the tumor volume of resection (P = 0.001), histological type (P < 0.001), and postoperative recurrence (P < 0.001) were the risk factors affecting the prognosis of children with WT. The results of the Cox proportional hazards model showed that only the histological type (P = 0.018) was the independent risk factor for the prognosis of WT.

CONCLUSION

The efficacy of multidisciplinary treatment for WT was satisfying. The histological type has important predictive value for the prognosis of WT, and the patient with unfavorable histology has a poor prognosis.

Wilms tumor in children: A multivariate analysis of prognostic factors, with emphasis on inferior vena cava/right atrium extension. Results from a single-center study

BACKGROUND

To identify prognostic factors for overall survival through the analysis of 132 patients with Wilms tumor followed at a single center, with emphasis on the inferior vena cava/right atrium extension.

METHODS

Retrospective analysis of overall survival using logistic regression models and including age, sex, clinical features, associated syndromes, comorbidities, tumor size before chemotherapy, stage, presence of metastatic disease and its site, invasion of adjacent structures, inferior vena cava/right atrium extension, laterality, tumor histology, chemotherapy protocol, and radiotherapy as potential risk factors.

RESULTS

From January 2000 through November 2021, 132 patients met the inclusion criteria, 64 females and 68 males; 15 (11.4%) patients presented with tumoral extension to inferior vena cava/right atrium and 44 had metastatic disease (33.3%). Based on logistic regression, the factors correlating to a fatal outcome were male sex (p = 0.046), high risk histology (p = 0.036), and the presence of metastatic disease (p = 0.003). None of the patients presenting inferior vena cava/right atrium extension died (p = 0.992). In a specific analysis of metastatic sites, hepatic metastasis alone showed correlation with a fatal outcome (p = 0.001).

CONCLUSION

These results underline the importance of identifying and treating metastatic disease and high-risk tumors. The female gender as a potential driver for a less aggressive disease is a new finding that deserves further investigation. The accurate identification of inferior vena cava/right atrium extension, subsequent preoperative chemotherapy, and resection with a skilled team promoted survival rates of all patients.

LEVEL OF EVIDENCE

II.

Management of intravascular thrombus in cases of bilateral Wilms tumor or horseshoe kidney

PURPOSE

To describe the oncologic and surgical management of bilateral Wilms tumor or Wilms tumor arising in a horseshoe kidney with intravenous tumor thrombus to help pediatric surgeons negotiate this rare and difficult anatomic circumstance.

METHODS

A single-institution, retrospective medical record review identified 4 cases of bilateral WT and one case of WT arising in a horseshoe kidney with intravenous tumor thrombus between 2009 and 2021. The presentation, imaging, chemotherapy regimen, intraoperative approach, and surgical and oncologic outcomes were reviewed for each of these patients.

RESULTS

All patients received a total of 12 weeks of neoadjuvant chemotherapy. In two patients, a staged approach to the bilateral tumors was undertaken with the first side being operated on after six weeks of therapy and the other side undergoing surgery after an additional six weeks of therapy. Of five patients, four underwent nephron-sparing surgery of all tumors and one underwent unilateral radical nephroureterectomy with contralateral nephron-sparing surgery. Tumor thrombectomy was performed in four of five cases; one patient demonstrated a complete response of the intravenous tumor thrombus to neoadjuvant chemotherapy and did not require thrombectomy. Three patients received adjuvant flank radiotherapy. Three patients developed medically managed stage II or III chronic kidney disease and no patient required renal replacement therapy or kidney transplant to date.

CONCLUSION

Nephron-sparing surgery is feasible and safe to perform in selected cases of bilateral Wilms tumor with intravascular thrombus by utilizing three-drug neoadjuvant chemotherapy, staged approaches to each kidney when appropriate, and detailed preoperative and/or intraoperative mapping of renal venous anatomy. Successful nephron-sparing surgery with tumor thrombectomy is dependent on a branched renal venous system or the presence of accessory renal veins.

LEVEL OF EVIDENCE

Level 4.

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.

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.

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.

Wilms tumour

Wilms tumour (WT) is a childhood embryonal tumour that is paradigmatic of the intersection between disrupted organogenesis and tumorigenesis. Many WT genes play a critical (non-redundant) role in early nephrogenesis. Improving patient outcomes requires advances in understanding and targeting of the multiple genes and cellular control pathways now identified as active in WT development. Decades of clinical and basic research have helped to gradually optimize clinical care. Curative therapy is achievable in 90% of affected children, even those with disseminated disease, yet survival disparities within and between countries exist and deserve commitment to change. Updated epidemiological studies have also provided novel insights into global incidence variations. Introduction of biology-driven approaches to risk stratification and new drug development has been slower in WT than in other childhood tumours. Current prognostic classification for children with WT is grounded in clinical and pathological findings and in dedicated protocols on molecular alterations. Treatment includes conventional cytotoxic chemotherapy and surgery, and radiation therapy in some cases. Advanced imaging to capture tumour composition, optimizing irradiation techniques to reduce target volumes, and evaluation of newer surgical procedures are key areas for future research.