Pediatric renal tumor epidemiology: Global perspectives, progress, and challenges

Current surgical approaches to pediatric renal tumors

Pediatric renal tumors are among the most common pediatric solid malignancies. Surgical resection is a key component in the multidisciplinary therapy for children with kidney tumors. Therefore, it is imperative that surgeons caring for children with renal tumors fully understand the current standards of care in order to provide appropriate surgical expertise within this multimodal framework. Fortunately, the last 60 years of international, multidisciplinary pediatric cancer cooperative group studies have enabled high rates of cure for these patients. This review will highlight the international surgical approaches to pediatric patients with kidney cancer to help surgeons understand the key differences and similarities between the European (International Society of Pediatric Oncology) and North American (Children's Oncology Group) recommendations.

Social Determinants of Health Influence on Survival in Wilms Tumor, Neuroblastoma, and Hepatoblastoma

BACKGROUND

The influence of social determinants of health (SDOH) on childhood cancer outcomes is complex and understudied. This study aimed to elucidate the influence of socioeconomic status (SES) and race on survival in Wilms tumor (WT), neuroblastoma (NB), and hepatoblastoma (HB).

METHODS

National Cancer Database was queried from 2004 to 2020 for pediatric patients (aged 0-18) with WT, NB, and HB. A SES composite score was created by combining quartiles for median household income and percent no high school degree (with higher scores reflecting greater disadvantage). Kaplan-Meier analyses and Cox regressions were performed to determine influencers on survival.

RESULTS

This study included 5218 patients with WT, 5851 with NB, and 1311 with HB. The distribution of race for WT, NB, and HB was 59 %, 65 %, and 55 % White non-Hispanic, and 18 %, 11 %, and 11 % Black non-Hispanic patients, respectively. Kaplan-Meier analyses revealed disparate outcomes with higher SES scores having worse survival for WT (p = 0.002) and NB (p = 0.011). In multivariable analysis of children with WT: age, higher SES score, comorbidities, tumor size, and bilateral and metastatic disease were associated with worse survival. For NB: age, urbanicity, higher SES score, Black non-Hispanic race/ethnicity, tumor size, metastatic disease, and chemotherapy were associated with worse survival. For HB: age, comorbidities, and metastatic disease were associated with worse survival.

CONCLUSION

After controlling for patient and tumor characteristics, there are significant associations between SDOH and worse survival for patients with WT and NB. Identification of social risk factors is critical for closing equity gaps and improving outcomes for children with solid tumors.

LEVEL OF EVIDENCE

Level III.

TYPE OF STUDY

Retrospective.

Paediatric Renal Tumors: A State-of-the-Art Review

PURPOSE OF REVIEW

Pediatric renal tumors comprise a wide range of conditions, both malignant and benign, that affect children and require a multidisciplinary approach for optimal diagnosis and treatment. This review offers an in-depth analysis of the epidemiology, diagnosis, treatment options, outcomes, and survival of major pediatric renal tumors.

RECENT FINDINGS

Wilms tumor, or nephroblastoma, is the most common form of renal tumor in children, characterized by growth from primitive renal cells. Standard treatment involves a combination of surgery, chemotherapy and, in some cases, radiation therapy, with the aim of removing the tumor, preventing recurrence and maximizing the chances of long-term recovery. Less common pediatric renal tumors, such as renal clear cell sarcoma, renal cell carcinoma, mesoblastic nephroma, and malignant rhabdoid tumor, require similarly careful and individualized management. Therapeutic strategies, which depend on the characteristics of the tumor, the stage of the disease and the individual response to therapy, may include surgery, chemotherapy, radiotherapy and, in some cases, molecular targeted therapies, immunotherapies and genetic and epigenetic therapies. The management of pediatric kidney tumors requires the involvement of a multidisciplinary team of specialists to ensure accurate evaluation, optimal treatments and long-term follow-up. The aim is to maximize the prospects for recovery and improve the quality of life of patients and their families. Advances in innovative, personalized therapies represent an important opportunity to further improve clinical outcomes in these patients.

Outcomes of children with clear cell sarcoma of kidney following NWTS strategies in Shanghai China (2003-2021)

BACKGROUND

Although clear cell sarcoma of kidney (CCSK) is rare, it is the second most common renal tumor in children after Wilms' tumor. NWTS and SIOP are two major groups which had made tremendous efforts on renal tumors, but the strategies are different, for NWTS follows the upfront surgery principle providing definite pathology and the SIOP follows the upfront chemotherapy principle, each has its own advantages. Here we aimed to evaluate the outcomes of CCSK in China following NWTS strategies to analyze the prognostic factors.

METHODS

For this multicenter retrospective study, a total of 54 patients were enrolled from three children's hospitals, between April 2003 and December 2021. Treatment comprised upfront radical nephrectomy, followed by radiotherapy and intensive chemotherapy. Clinical records were regularly updated. Prognostic factors and survival rates were evaluated.

RESULTS

The 54 enrolled patients had a median age of 37 months (range, 4 months to 11.4 years). The stage distribution was 16% stage I (n = 9), 30% stage II (n = 16), 39% stage III (n = 21), and 15% stage IV (n = 8). Among stage IV, metastasis sites included the lung (n = 6), bone (n = 1), and intra-orbital/cervical lymph node (n = 1). After a median follow-up of 5.6 years, the 5-year event-free survival (EFS) was 82.4±5.4%, and overall survival was 88.1±4.6%. The EFS was 100% for stage I, 93.8 ±6.1% for stage II, 71.1±10.0% for stage III, and 68.6±18.6% for stage IV. Univariate analysis revealed that staging (III/IV), tumor rupture, and inferior vena cava tumor thrombus were inferior prognostic factors. Multivariate analysis revealed that tumor rupture was independent poor prognostic factor (P = 0.01, HR 5.9). Among relapsed patients, relapse occurred a median of 11 months after diagnosis (range, 4-41 months), and 50% (4/8) achieved a second complete remission after multiple treatment. None of the six lung metastasis patients received lung RT, only one patient developed a relapse and was salvaged by RT after relapse.

CONCLUSIONS

Tumor rupture was independent poor prognostic factor. Upfront surgery of NWTS strategies can make a definite pathology diagnosis, but how to reduce tumor rupture during surgery is important especially in developing countries. The outcomes of patients with stage I-III CCSK in China were comparable to findings in other developed countries. Better outcomes were achieved in stage IV CCSK by using an intensive chemotherapy regimen including carboplatin, which require further confirmation by AREN0321. Lung RT may be safely omitted in selected patients who achieve a compete radiographic response after 6 weeks of systemic treatment (including surgery). Treatment should be encouraged even in CCSK cases with metastasis and relapse.

Nomogram for personalized prognostic assessment of children with favorable histology Wilms tumor: A retrospective analysis

OBJECTIVE

This retrospective study aimed to construct and validate a nomogram for personalized prognostic assessment of favorable histology Wilms tumor (FHWT) based on clinical and pathological variables.

METHODS AND MATERIALS

This was a retrospective study collected data from patients who underwent surgery for FHWT between March 2007 and November 2022 at Beijing Children's Hospital. Univariate and multivariate Cox proportional hazards regression analyses were conducted to determine the significance variables and constructed the nomogram in predicting event-free survival (EFS) in FHWT patients.

RESULTS

A total of 401 FHWT patients were included in the study, with the median age of the patients was 3.4 years. The overall 1-, 3-, and 5-year OS rates were 98.2%, 96.3%, and 93.9%. The 1-, 3-, and 5-year EFS rates were 91.2%, 88.2%, and 86.6%. Subgroup analysis revealed age greater than 2 years was associated with a worse prognosis than age less than or equal to 2 years (P < 0.001), and patients with high-risk Wilms tumors were associated with a higher rate of recurrence and death (P < 0.001). Multivariate analysis showed that age (HR: 2.449, 95%CI: 1.004-5.973), stage (HR: 1.970, 95% CI:1.408-2.756), and histological risk (HR:9.414, 95% CI: 4.318-20.525) were identified as independent predictors of EFS (P < 0.05) and used to construct the nomogram. The prognostic nomogram demonstrated good calibration, great clinical utility, and the time-dependent receiver operating curve analysis showed that the nomogram had precise predictability, with area under the curve values of 0.85(95CI:0.796-0.913), 0.85(95CI:0.80-0.91), and 0.88(95CI:0.839-0.937) for 1-,3-year and 5-year EFS.

CONCLUSION

This study provides valuable insights into the clinical characteristics and outcomes of FHWT patients. Accurate staging and histological risk assessment are important in predicting outcomes, and the prognostic nomogram we developed can be a useful tool for clinicians to assess patient prognosis and make informed treatment decisions.

Race and Ethnic Group Enrollment and Outcomes for Wilms Tumor: Analysis of the Current Era Children's Oncology Group Study, AREN03B2

BACKGROUND

To review race and ethnic group enrollment and outcomes for Wilms tumor (WT) across all 4 risk-assigned therapeutic trials from the current era Children's Oncology Group Renal Tumor Biology and Risk Stratification Protocol, AREN03B2.

STUDY DESIGN

For patients with WT enrolled in AREN03B2 (2006 to 2019), disease and biologic features, therapeutic study-specific enrollment, and event-free (EFS) and overall (OS) 4-year survival were compared between institutionally reported race and ethnic groups.

RESULTS

Among 5,146 patients with WT, no statistically significant differences were detected between race and ethnic groups regarding subsequent risk-assigned therapeutic study enrollment, disease stage, histology, biologic factors, or overall EFS or OS, except the following variables: Black children were older and had larger tumors at enrollment, whereas Hispanic children had lower rates of diffuse anaplasia WT and loss of heterozygosity at 1p. The only significant difference in EFS or OS between race and ethnic groups was observed among the few children treated for diffuse anaplasia WT with regimen UH-1 and -2 on high-risk protocol, AREN0321. On this therapeutic arm only, Black children showed worse EFS (hazard ratio = 3.18) and OS (hazard ratio = 3.42). However, this finding was not replicated for patients treated with regimen UH-1 and -2 under AREN03B2 but not on AREN0321.

CONCLUSIONS

Race and ethnic group enrollment appeared constant across AREN03B2 risk-assigned therapeutic trials. EFS and OS on these therapeutic trials when analyzed together were comparable regarding race and ethnicity. Black children may have experienced worse stage-specific survival when treated with regimen UH-1 and -2 on AREN0321, but this survival gap was not confirmed when analyzing additional high-risk AREN03B2 patients.