Translocation Renal Cell Carcinoma in a Child Previously Treated for Infantile Fibrosarcoma

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.

Factors Associated with Survival From Xp11.2 Translocation Renal Cell Carcinoma Diagnosis-A Systematic Review and Pooled Analysis

Purpose: Xp11.2 translocation renal cell carcinoma (Xp11.2 tRCC) is a rare subtype of renal cell carcinoma (RCC), characterized by translocations of Xp11.2 breakpoints, involving of the transcription factor three gene (TFE3). The aim of our study was to comprehensively characterize the clinical characteristics and outcomes, and to identify risk factors associated with OS and PFS in Xp11.2 tRCC patients.

Methods: Literature search on Xp11.2 tRCC was performed using databases such as pubmed EMBASE and Web of Science. Studies were eligible if outcomes data (OS and/or PFS) were reported for patients with a histopathologically confirmed Xp11.2 tRCC. PFS and OS were evaluated using the univariable and multivariable Cox regression model.

Results: There were 80 eligible publications, contributing 415 patients. In multivariable analyses, the T stage at presentation was significantly associated with PFS (HR: 3.87; 95% CI: 1.70 to 8.84; p = 0.001). The median time of PFS was 72 months. In the multivariable analyses, age at diagnosis (HR: 2.16; 95% CI: 1.03 to 4.50; p = 0.041), T stage at presentation (HR: 4.44; 95% CI: 2.16 to 9.09; p < 0.001) and metastasis status at presentation (HR: 2.67; 95% CI: 1.12 to 6.41; p = 0.027) were all associated with OS, with a median follow-up time of 198 months.

Conclusion: T stage at presentation is the only factor that is associated with both PFS and OS in patients with Xp11.2 tRCC. Also, patients over 45 or with metastases are more likely to have poorer OS.