Case Report: Diagnostic dilemma: rebound thymic hyperplasia mimicking mediastinal relapse following chemoimmunotherapy in pediatric jejunal Burkitt lymphoma
- 1Department of Oncology, Postgraduate Union Training Base of Xiangyang No. 1 People’s Hospital, Hubei University of Medicine
- 2Department of Thoracic Surgery, Xiangyang Central Hospital, Hubei University of Arts and Science
- 3Department of Oncology, Xiangyang Central Hospital, Hubei University of Arts and Science
Abstract
Background: Pediatric sporadic Burkitt lymphoma (BL) typically presents with gastrointestinal involvement; primary mediastinal disease is exceedingly rare. Rebound thymic hyperplasia (RTH) is a benign regenerative process following chemotherapy that can radiologically mimic mediastinal relapse, creating significant diagnostic challenges in post-treatment surveillance.
Case presentation: An 8-year-old male was diagnosed with St. Jude stage III Burkitt lymphoma (BL) following the emergency resection of a jejunal mass. After receiving risk-adapted chemoimmunotherapy, he achieved a complete metabolic response. Three months post-treatment, routine surveillance computed tomography (CT) revealed a new anterior mediastinal soft tissue mass, magnetic resonance imaging (MRI) revealing T2 hyperintensity in the anterior mediastinal lesion without restricted diffusion, while subsequent PET/CT demonstrated mildly increased FDG uptake, raising immediate clinical concern for disease relapse. To rule out malignancy, a CT-guided percutaneous biopsy was performed. Histopathological analysis revealed normal thymic microarchitecture containing Hassall’s corpuscles. The final imaging and pathological findings supported a diagnosis of chemotherapy-induced rebound thymic hyperplasia (RTH).
Conclusion: Cytotoxic therapy induces profound thymic involution, often followed by striking regenerative expansion upon treatment cessation. Recognizing RTH is paramount to avoid misdiagnosing neoplastic recurrence and administering unwarranted therapies. This case highlights need to integrate advanced imaging and tissue biopsy when evaluating new mediastinal opacities in pediatric lymphoma survivors.
Related
- Localized lymphoid hyperplasia with prominent IgG4-positive plasma cells in the inferior turbinate mimicking IgG4-related disease
- Delayed Diagnosis of Germline GATA2 Deficiency Following Severe Adolescent Iliocaval Thrombosis and Decade-Long Monocytopenia: Diagnostic and Testing Pitfalls.
- Effects of Lindera aggregata Linderae Radix on Testosterone Propionate-Induced Benign Prostatic Hyperplasia in Rats
- Compartmental immune responses and biomarker discordance after neoadjuvant chemoimmunotherapy in resectable non-small cell lung cancer
- CT radiomics-histopathological correlation for mediastinal lymph node staging in non-small cell lung cancer
BibTeX
@article{lin2026case,
title = {{Case Report: Diagnostic dilemma: rebound thymic hyperplasia mimicking mediastinal relapse following chemoimmunotherapy in pediatric jejunal Burkitt lymphoma}},
author = {Meifang Lin and Zengwang Zhang and Hao Zhang and Dongdong Zhang},
journal = {Frontiers in Immunology},
year = {2026},
month = oct,
doi = {10.3389/fimmu.2026.1910294},
url = {https://www.frontiersin.org/articles/10.3389/fimmu.2026.1910294/full},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Case Report: Diagnostic dilemma: rebound thymic hyperplasia mimicking mediastinal relapse following chemoimmunotherapy in pediatric jejunal Burkitt lymphoma
AU - Meifang Lin
AU - Zengwang Zhang
AU - Hao Zhang
AU - Dongdong Zhang
PY - 2026
DA - 2026/10/15
JO - Frontiers in Immunology
DO - 10.3389/fimmu.2026.1910294
UR - https://www.frontiersin.org/articles/10.3389/fimmu.2026.1910294/full
AB - Background: Pediatric sporadic Burkitt lymphoma (BL) typically presents with gastrointestinal involvement; primary mediastinal disease is exceedingly rare. Rebound thymic hyperplasia (RTH) is a benign regenerative process following chemotherapy that can radiologically mimic mediastinal relapse, creating significant diagnostic challenges in post-treatment surveillance. Case presentation: An 8-year-old male was diagnosed with St. Jude stage III Burkitt lymphoma (BL) following the emergency resection of a jejunal mass. After receiving risk-adapted chemoimmunotherapy, he achieved a complete metabolic response. Three months post-treatment, routine surveillance computed tomography (CT) revealed a new anterior mediastinal soft tissue mass, magnetic resonance imaging (MRI) revealing T2 hyperintensity in the anterior mediastinal lesion without restricted diffusion, while subsequent PET/CT demonstrated mildly increased FDG uptake, raising immediate clinical concern for disease relapse. To rule out malignancy, a CT-guided percutaneous biopsy was performed. Histopathological analysis revealed normal thymic microarchitecture containing Hassall’s corpuscles. The final imaging and pathological findings supported a diagnosis of chemotherapy-induced rebound thymic hyperplasia (RTH). Conclusion: Cytotoxic therapy induces profound thymic involution, often followed by striking regenerative expansion upon treatment cessation. Recognizing RTH is paramount to avoid misdiagnosing neoplastic recurrence and administering unwarranted therapies. This case highlights need to integrate advanced imaging and tissue biopsy when evaluating new mediastinal opacities in pediatric lymphoma survivors.
SN - 1664-3224
ER -