Breast Relapse of Pediatric B-Cell Acute Lymphoblastic Leukemia After CAR-T Therapy Detected by 18F-FDG PET/CT

Anticancer Res. 2024 May;44(5):2243-2245. doi: 10.21873/anticanres.17032.


Background: B-cell acute lymphoblastic leukemia (B-ALL) is the most common childhood malignancy. Medullary and extramedullary disease relapse is a well-known occurrence in B-ALL pediatric patients treated with standard chemo-immunotherapy and, more recently, with chimeric antigen receptor (CAR)-T cell therapy. 18F-Fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) emerges as a sensitive imaging tool for detecting disease relapse at extra-medullary sites, with only limited literature evidence in the CAR-T therapy setting.

Case report: In a 12-year-old female treated with CAR-T therapy for B-ALL relapse, 18F-FDG PET/CT scan performed for surveillance, after disease remission, detected a solitary and clinically occult relapse in the breast parenchyma that was histologically confirmed.

Conclusion: At our knowledge, this is the first report about a pediatric B-ALL patient with a solitary and occult breast relapse after CAR-T therapy, early discovered by 18F-FDG PET/CT during disease monitoring.

Keywords: 18F-FDG; B-cell acute lymphoblastic leukemia; PET/CT; breast; chimeric antigen receptor T cell therapy; pediatric.

Publication types

  • Case Reports

MeSH terms

  • Breast Neoplasms / diagnostic imaging
  • Breast Neoplasms / pathology
  • Breast Neoplasms / therapy
  • Child
  • Female
  • Fluorodeoxyglucose F18*
  • Humans
  • Immunotherapy, Adoptive* / adverse effects
  • Immunotherapy, Adoptive* / methods
  • Neoplasm Recurrence, Local / diagnostic imaging
  • Neoplasm Recurrence, Local / pathology
  • Positron Emission Tomography Computed Tomography* / methods
  • Precursor B-Cell Lymphoblastic Leukemia-Lymphoma* / diagnostic imaging
  • Precursor B-Cell Lymphoblastic Leukemia-Lymphoma* / therapy
  • Radiopharmaceuticals


  • Fluorodeoxyglucose F18
  • Radiopharmaceuticals