case_images: PMC9393674_01
case_images: Clinical examination results. (A) Expression of AL cells at
  diagnosis. (B) MRD in BM was negative after haplo-SCT when the
  neurological symptoms appeared. (C) MRI demonstrated multiple
  abnormal hyperintensity lesions surrounded by edema in
  cerebellar vermis and left cerebellar hemisphere. (D and E) The
  intracranial neoplasm was considered intracranial invasion of
  leukemia by dynamic enhanced MRI. (F and G) The brain tissue
  showed that diffuse infiltration of small round cells with deep
  staining. (H) The tumor cells stained positive for CD19. (I) The
  tumor cells stained positive for CD20. (J) The tumor cells
  stained approximately 75% for Ki-67. (K) EBER in
  situ hybridization was sparsely sparse positive.
  MRD: minimal residual disease; BM: bone marrow; SCT: stem cell
  transplantation; MRI: magnetic resonance imaging; EBER:
  Epstein-Barr virus-encoded RNA; AL: all events; SSC-A: side
  scatter-area.
case_images: 10.1177_09636897221117532-fig1.jpg
case_images: PMC9393674_01_10.1177_09636897221117532-fig1.jpg
case_images: fig1-09636897221117532
case_images: The patient's leukemia cells expressed CD19+CD22+CD10+CD38+CD20- (Fig. 1A). After admission to our center, the patient was MRD-negative in the BM (Fig. 1B), and donor chimerism in the BM was at 100%. Magnetic resonance imaging (MRI) demonstrated multiple abnormal hyperintensity lesions surrounded by edema in the cerebellar vermis and the left cerebellar hemisphere (Fig. 1C). Dynamic enhanced MRI demonstrated intracranial neoplasm surrounded by edema in the cerebellar vermis and the left cerebellar hemisphere, which was considered to be an intracranial invasion of leukemia (Fig. 1D, E). The biopsy of the brain tissue showed diffuse infiltration of small round cells with deep staining (Fig. 1F, G). The tumor cells stained positive for CD19, CD20, Ki-67 (approximately 75%) (Fig. 1H-J), and C-myc (approximately 25%). Although the result of EBV-encoded RNA (EBER) in situ hybridization was sparsely positive (Fig. 1K), NGS of the brain tissue was positive for EBV.