Renal cell carcinoma in children and adolescents: Single-center experience and literature review

Outcome after treatment with axitinib in children, young adults, and adults with renal cell carcinoma: a narrative review

Renal cell carcinoma (RCC) is a very rare type of renal cancer in children and young adults. When metastasized or recurrent, no standards of care are available, and outcome is still poor. The tyrosine kinase inhibitor axitinib is approved for treatment of RCC in adults, but its effects in children and young adults with RCC remains unclear. Due to the histological and biological differences between children and adults, it is difficult to extrapolate knowledge on treatments from the adult to the pediatric and young adult setting. This paper summarizes the clinical characteristics and outcomes of patients with RCC who were treated with axitinib, with the aim to gain insight in the clinical efficacy of this compound in this young patient group.

TFE3-Rearranged Renal Cell Carcinoma With Osseous Metaplasia: A Case Report of a Rare Entity With an Unusual Finding

TFE3-rearranged renal cell carcinoma (RCC) is a rare subtype of renal tumor that typically affects the pediatric age group. Previous exposure to chemotherapy agents increases the possibility of having this subtype. Morphologically, it displays a broad spectrum of growth patterns, but it can be distinguished by the presence of melanin pigment or psammoma bodies. Osseous metaplasia is an uncommon morphological finding in this particular subtype, and it has been reported in two cases in the literature. We describe the third case of TFE3-rearranged renal cell carcinoma with osseous metaplasia in a healthy 13-year-old male, presenting with worsening abdominal pain and hematuria.

Identification of key genes and signalling pathways in clear cell renal cell carcinoma: An integrated bioinformatics approach

BACKGROUND

Clear cell Renal Cell Carcinoma (ccRCC) is one of the most prevalent types of kidney cancer. Unravelling the genes responsible for driving cellular changes and the transformation of cells in ccRCC pathogenesis is a complex process.

OBJECTIVE

In this study, twelve microarray ccRCC datasets were chosen from the gene expression omnibus (GEO) database and subjected to integrated analysis.

METHODS

Through GEO2R analysis, 179 common differentially expressed genes (DEGs) were identified among the datasets. The common DEGs were subjected to functional enrichment analysis using ToppFun followed by construction of protein-protein interaction network (PPIN) using Cytoscape. Clusters within the DEGs PPIN were identified using the Molecular Complex Detection (MCODE) Cytoscape plugin. To identify the hub genes, the centrality parameters degree, betweenness, and closeness scores were calculated for each DEGs in the PPIN. Additionally, Gene Expression Profiling Interactive Analysis (GEPIA) was utilized to validate the relative expression levels of hub genes in the normal and ccRCC tissues.

RESULTS

The common DEGs were highly enriched in Hypoxia-inducible factor (HIF) signalling and metabolic reprogramming pathways. VEGFA, CAV1, LOX, CCND1, PLG, EGF, SLC2A1, and ENO2 were identified as hub genes.

CONCLUSION

Among 8 hub genes, only the expression levels of VEGFA, LOX, CCND1, and EGF showed a unique expression pattern exclusively in ccRCC on compared to other type of cancers.

Factors associated with survival in paediatric and adolescent renal cell carcinoma: a population-based study

BACKGROUND

The purpose of this study was to conduct a population-based study to determine the prognosis of renal cell carcinoma (RCC) in children and adolescents.

METHODS

Patients with RCC who were registered in the Surveillance, Epidemiology, and End Results (SEER) program between 2000 and 2018 had their demographic and clinical characteristics evaluated retrospectively. The log-rank test was used to compare survival curves. Kaplan-Meier estimates were used to generate survival curves based on various factors. To identify factors associated with overall survival, Cox proportional-hazards regression was used.

RESULTS

A total of 251 patients were enrolled in the study. For all patients, the overall survival (OS) rates at 3- and 5- year were 93.5% and 92.0%, respectively. A multivariable study revealed that the following factors were independently associated with overall survival: sex, race, histologic type, SEER stage, AJCC stage, and type of surgery. Cox analysis showed that white patients had the lowest risk of mortality (hazard ratio (HR) 2.58, 95% confidence interval (CI), 1.33-4.99; P = 0.005), compared with black patients. Patients having metastatic disease had significantly higher mortality risk (HR 43, 95% CI, 14.8-125; P < 0.001) than the patients with localized tumour.

CONCLUSIONS

Our study emphasizes the importance of race, SEER stage, and surgery in the prognosis of paediatric RCC, providing valuable epidemiological evidence for clinical practice. Economic studies assessing a race/ethnic group specific strategy are also required.

MRI Characteristics of Pediatric and Young-Adult Renal Cell Carcinoma: A Single-Center Retrospective Study and Literature Review

Pediatric renal cell carcinoma (RCC) is a rare malignancy. Magnetic resonance imaging (MRI) is the preferred imaging modality for assessment of these tumors. The previous literature has suggested that cross-sectional-imaging findings differ between RCC and other pediatric renal tumors and between RCC subtypes. However, studies focusing on MRI characteristics are limited. Therefore, this study aims to identify MRI characteristics of pediatric and young-adult RCC, through a single-center case series and literature review. Six identified diagnostic MRI scans were retrospectively assessed, and an extensive literature review was conducted. The included patients had a median age of 12 years (63-193 months). Among other subtypes, 2/6 (33%) were translocation-type RCC (MiT-RCC) and 2/6 (33%) were clear-cell RCC. Median tumor volume was 393 cm³ (29-2191 cm³). Five tumors had a hypo-intense appearance on T2-weighted imaging, whereas 4/6 were iso-intense on T1-weighted imaging. Four/six tumors showed well-defined margins. The median apparent diffusion coefficient (ADC) values ranged from 0.70 to 1.20 × 10^-3 mm²/s. In thirteen identified articles focusing on MRI characteristics of MiT-RCC, the majority of the patients also showed T2-weighted hypo-intensity. T1-weighted hyper-intensity, irregular growth pattern and limited diffusion-restriction were also often described. Discrimination of RCC subtypes and differentiation from other pediatric renal tumors based on MRI remains difficult. Nevertheless, T2-weighted hypo-intensity of the tumor seems a potential distinctive characteristic.

Unusual Renal Mass in a Pediatric Patient

Renal cell carcinoma (RCC) is rare in the pediatric population, comprising about 5% of renal neoplasms in children.¹ Out of all childhood cases of RCC, translocation RCCs (tRCC) is the most common.² It is well described in the literature that exposure to alkylating agents such as cyclophosphamide and/or topoisomerase II inhibitors such as doxorubicin and etoposide, is a risk factor for the development of Xp11 (or TFE3) tRCC.³ Herein is a case of tRCC development in a patient with history of exposure to topoisomerase II inhibitors and alkylating agents to treat a common childhood malignancy.

Recent Advances in Renal Medullary Carcinoma

Renal medullary carcinoma (RMC) is a rare renal malignancy that has been associated with sickle hemoglobinopathies. RMC is aggressive, difficult to treat, and occurs primarily in adolescents and young adults of African ancestry. This cancer is driven by the loss of SMARCB1, a tumor suppressor seen in a number of primarily rare childhood cancers (e.g., rhabdoid tumor of the kidney and atypical teratoid rhabdoid tumor). Treatment options remain limited due in part to the limited knowledge of RMC biology. However, significant advances have been made in unraveling the biology of RMC, from genomics to therapeutic targets, over the past 5 years. In this review, we will present these advances and discuss what new questions exist in the field.