Mediastinal Teratoma with Nephroblastomatous Elements: Case Report, Literature Review, and Comparison with Maturing Fetal Glomerulogenic Zone/Definitive Zone Ratio and Nephrogenic Rests

Int J Mol Sci. 2024 Nov 19;25(22):12427. doi: 10.3390/ijms252212427.

Abstract

Extrarenal teratoid Wilms' tumor (TWT) is a variant of Wilms' tumor with fewer than 30 cases reported in the literature. It comprises more than 50% heterologous tissue and presents a significant diagnostic challenge due to its complex histology. We report an unusual case of mediastinal teratoma with nephroblastomatous elements in an 8-year-old female. The patient presented with respiratory distress, fever, weight loss, and a large anterior mediastinal mass. Imaging revealed a heterogeneous tumor containing fat, fluid, and calcification, suggestive of a teratoma. Surgical resection confirmed a mature cystic teratoma with foci of nephroblastoma. Pathological analysis demonstrated a mixture of ectodermal, mesodermal, and endodermal tissues alongside nephroblastomatous components. Immunohistochemistry was positive for Wilms Tumor 1 and other relevant markers, confirming the diagnosis. The patient had an uneventful postoperative course and was discharged after three days. This case adds to the growing body of research on extrarenal TWT, particularly its occurrence in the mediastinum, a rare site for such tumors. A literature review highlighted that extrarenal TWT often affects children, typically presenting in the retroperitoneum or sacrococcygeal regions, with varying recurrence rates and long-term outcomes. This case underscores the importance of histopathological and immunohistochemical analysis in diagnosing TWT and differentiating it from other mediastinal tumors to ensure appropriate treatment planning, emphasizing the need for long-term follow-up due to the potential for recurrence or metastasis. This paper also provides an in-depth look at nephron development and nephrogenic rests, highlighting the structural and functional aspects of nephrogenesis and the factors that disrupt it in fetal kidneys.

Keywords: Nephroblastoma; Teratoid Wilms’ tumor; Wilms’ tumor; immunohistochemistry; narrative review.

Publication types

  • Case Reports
  • Review

MeSH terms

  • Child
  • Female
  • Humans
  • Mediastinal Neoplasms* / diagnosis
  • Mediastinal Neoplasms* / pathology
  • Teratoma* / diagnosis
  • Teratoma* / pathology
  • Wilms Tumor* / diagnosis
  • Wilms Tumor* / pathology
  • Wilms Tumor* / surgery

Grants and funding

The senior (corresponding) author’s research was funded by the generosity of the Children’s Hospital of Eastern Ontario, Ottawa, Ontario, Canada; the Stollery Children’s Hospital Foundation and supporters of the Lois Hole Hospital for Women through the Women and Children’s Health Research Institute (WCHRI, Grant ID #: 2096), Edmonton, Alberta, Canada. Additional funding received from the senior (corresponding) author included the Hubei Province Natural Science Funding for Hubei University of Technology (100-Talent Grant for Recruitment Program of Foreign Experts Total Funding: Digital PCR and NGS-based diagnosis for infection and oncology, 2017–2022); Österreichische Krebshilfe Tyrol (Krebsgesellschaft Tirol, the Austrian Tyrolean Cancer Research Institute, and the Austrian Research Fund); the Canadian Foundation for Women’s Health; the Cancer Research Society; the Canadian Institutes of Health Research; and the Saudi Cultural Bureau, Ottawa, Canada. The funders had no role in study design, data collection, analysis, the decision to publish, or manuscript preparation.