Renal Tumors in Children Younger Than 12 Months of Age: A 65-Year Single Institution Review

Incidence patterns of childhood non-Wilms renal tumors: Comparing data of the Nationwide Registry of Childhood Hematological Malignancies and Solid Tumors (NARECHEM-ST), Greece, and the Surveillance, Epidemiology, and End Results Program (SEER), USA

BACKGROUND

We used, for the first time, data registered in the Nationwide Registry for Childhood Hematological Malignancies and Solid Tumors (NARECHEM-ST)-Greece to estimate incidence/time trends of the rare childhood (0-14 years) non-Wilms tumors (non-WT), and compared the results of malignant non-WT to those from the Surveillance, Epidemiology, and End Results Program (SEER)-USA.

METHODS

Fifty-five cases (n = 33 malignant-only) were extracted from NARECHEM-ST (2001-2020) and 332 malignant cases from SEER (1990-2017). To allow between-country comparisons, age-standardized incidence rates (AIR) of malignant-only non-WT were calculated, and temporal trends were evaluated using Poisson and joinpoint regressions.

RESULTS

In NARECHEM-ST, malignant and non-malignant non-WT accounted for 22.6% of all renal tumors. Among malignant tumors, the AIR was 1.0/106 children in Greece, similar to that calculated for SEER, USA (AIR=0.9/106). The proportion of infant malignant and non-malignant non-WT was 27% (20% before 6 months) in NARECHEM-ST. Most common non-WT in Greece were congenital mesoblastic nephromas (CMN) diagnosed mainly in infancy (CIR=7.2/106). The proportion of infant malignant non-WT was 20% in SEER (AIRinfancy=2.5/106), mainly attributed to rhabdoid tumors (CIR=1.6/106). The male-to-female (M:F) ratio of malignant non-WT was 0.9 in NARECHEM-ST vs. 1.2 in SEER, whereas boys outnumbered girls with clear cell sarcoma in NARECHEM-ST (M:F=4.0). Lastly, significantly increasing trends in incidence rates were noted in NARECHEM-ST [+ 6.8%, 95% confidence intervals (CI): 0.5, 13.3] and in SEER (+7.3%, 95%CI: 5.6, 9.0).

CONCLUSIONS

Observed incidence, time trends and sociodemographic variations of non-WT may reflect differential registration practices and healthcare delivery patterns including differences regarding surveillance, coding and treatment practices.

Surgical management of cellular congenital mesoblastic nephroma in a neonate: a case report and review of literature

Background

Congenital mesoblastic nephroma (CMN) is the most common type of renal stromal tumor in neonates. It is classified into cellular, classical, and mixed types. The multidisciplinary management approach is the mainstay of management. We are reporting a case of neonatal congenital mesoblastic nephroma in a full-term boy with intrauterine growth restriction and hypertension managed effectively in our institution.

Case presentation

A full-term boy with intrauterine growth restriction (IUGR) with a birth weight of 2.3 kg, referred at birth with an abdominal mass. His antenatal scan at 35 weeks showed a cystic abdominal mass. On delivery, a huge visible abdominal mass of cystic consistency and smooth surface was noticed at the right side of the abdomen. blood pressure was 98/75 mmHg. It was responsive to hydralazine. Aldosterone and renin were significantly elevated at more than 100 and 500 ng/dl, respectively. Serum neurone-specific enolase (NSE) was 35 ng/ml while alfa feto protein was (AFP) 50,000 kIU/L. An abdominal ultrasound scan revealed an ill-defined large heterogeneous mass of 6.09 × 6.5 × 5.77 cm that arises from the right kidney. A computed tomography scan confirmed a right kidney mass with peripheral claw sign of the normal right renal tissue. It was crossing the midline and causing a mass effect on the adjacent structures. The right renal artery and vein were compressed and shifted posteriorly and inferomedially. Right radical nephrectomy was performed via a right lower transverse incision. The tumor was completely excised with a tumor weight of 270 g and a size of 10.5 × 8 × 5.5 cm. Histopathological diagnosis was mesoblastic nephroma of a cellular type which was confirmed by immunohistochemistry. Post-operatively, the blood pressure has significantly reduced and antihypertensive medications were eventually weaned off. The multidisciplinary team decided to preserve chemotherapy only in case of recurrence. At 3 months follow-up, no features of recurrence were noticed based on surveillance ultrasonography.

Conclusion

Mesoblastic nephroma should be considered in any newborn with renal mass. The multidisciplinary team approach with aggressive management of hypertension, detailed radiological investigation, and complete tumor resection is fundamental for obtaining an excellent outcome for such entities.

FOXO3a inhibits nephroblastoma cell proliferation, migration and invasion, and induces apoptosis through downregulating the Wnt/β‑catenin signaling pathway

Forkhead transcription factor O subfamily 3A (FOXO3a) is an important tumor suppressor gene that is expressed in renal tissue and has been reported to be downregulated in clear cell renal cell carcinoma (CCRCC). Notably, the overexpression of FOXO3a was previously discovered to inhibit the progression of CCRCC. However, the expression levels of FOXO3a in nephroblastoma cell lines remain unknown. The present study aimed to investigate the expression levels of FOXO3a in nephroblastoma cell lines and to determine the mechanism of action of the biological functions of FOXO3a. Western blotting and reverse transcription‑quantitative PCR were used to analyze the expression levels of FOXO3a in nephroblastoma cell lines. Subsequently, the effects of the overexpression of FOXO3a and the genetic knockdown of the Wnt/β‑catenin signaling protein Axin‑2 on the biological functions were determined through Cell Counting Kit‑8, cell colony formation assays, scratch and Transwell assay and flow cytometric analysis experiments. The expression levels of FOXO3a were discovered to be downregulated in nephroblastoma cell lines. The overexpression of FOXO3a inhibited the proliferation, invasion and migration of nephroblastoma cells, while inducing apoptosis. Furthermore, the overexpression of FOXO3a downregulated the expression levels of β‑catenin and Cyclin‑D1 proteins involved in the Wnt/β‑catenin signaling pathway. Cell proliferation and the migration and invasion ability of 17‑94 cells in shRNA‑Axin2‑2 group were promoted. Cell apoptosis was predominantly increased by overexpressed FOXO3a, which was reversed by shRNA‑Axin2‑1. The biological effects of overexpressing FOXO3a on nephroblastoma were reversed after activation of Wnt/β‑catenin. In conclusion, the findings of the present study suggested that FOXO3a may inhibit nephroblastoma cell proliferation, migration and invasion, while inducing apoptosis, by downregulating the Wnt/β‑catenin signaling pathway. These results may provide a novel method for the early diagnosis and precise treatment of nephroblastoma.

Neonatal Renal Tumors

Renal tumors are rare in the neonatal period. Although some may be detected prenatally, a greater proportion present after birth, most often with a palpable abdominal mass with or without other associated symptoms. Cross-sectional imaging is typically followed by radical nephrectomy to make a specific histologic diagnosis to determine the need for additional therapy. This article reviews the clinical presentation, workup, treatment, and outcomes for neonates with some of the more common renal tumors seen in this population.

Renal Tumors in Children and Young Adults Older Than 5 Years of Age

Renal masses are most common in children between ages 1 to 3 years, with less known about renal tumors in older children and young adults. The aim of this study was to review the presentation, demographics, histology, and outcomes in patients over 5 years of age with renal tumors compared with younger children. 111 renal tumors were diagnosed in patients 5 years of age and older (median, 7 y; range, 5 to 31 y) between 1950 and 2017 at a single institution. Wilms tumor (WT) was the most common histology in 84 patients (75%), followed by renal cell carcinoma in 12 patients (10.7%). Abdominal pain was the most common presenting symptom (46%) followed by hematuria (28.8%), and a palpable abdominal mass (24.3%). For WT, older children more commonly presented with advanced-stage disease (stages 3 and 4) than younger children (57.7% vs. 11.5%; P<0.001). Event-free survival (EFS) and overall survival (OS) for favorable histology WT were not different between younger and older children (OS, P=0.43; EFS, P=0.46). In this cohort, older children more frequently present with variable signs and symptoms, less common histopathologies although WT was still most frequent, and more advanced-stage disease compared with younger cohorts, but without differences in EFS or OS.

Unusual Presentation of Wilms' Tumor as Umbilical Granuloma

We report an unusual presentation of a Wilms' tumor in an 8-month-old child, incidentally detected by ultrasonography for an umbilical granuloma. A patent vitellointestinal duct anomaly required surgical excision in the same sitting as the nephroureterectomy. The case is reported for the unusual coexistence and the management implications.