case_images: PMC11148225_01
case_images: Examples of spinal sagittal T1-weighted MRI of the patient. (A) On admission. (B) After first cycle of therapy. (C) After second cycle of therapy. Abnormal high signals on T1 images are shown circled in red.
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case_images: On admission, our spine MRI confirmed the previous results ( Figure 1A ). However, spine MRI showed no significant improvement in MS lesions ( Figure 1B ). Fortunately, MRI showed that spinal MS lesions were obviously shrunken ( Figure 1C ).
case_images: Spine tissue and bone marrow (BM) aspirate examinations and results of karyotype and fluorescence in situ hybridization (FISH) analysis. (A) Histopathology of spinal cord (hematoxylin and eosin staining; magnification, x400). (B) BM aspirate shows atypical acute promyelocytic leukemia morphology (Wright-Giemsa staining; magnification, x1,000). (C) BM aspirate showed that promyelocytes were myeloperoxidase (MPO) positivity (MPO staining; magnification, x1,000). (D) Chromosome analysis of the BM reveals a normal male karyotype. (E, F) Metaphase FISH analysis of the patient. (E) The standard dual-color, dual-fusion probe set probe set for t(15;17) shows the presence of two red signals (PML) and three green signals (RARalpha), suggesting RARalpha rearrangement; (F) The RARalpha break-apart probe detects separated red signals (RARalpha). (G) Sanger sequencing analysis demonstrates PLZF::RARalpha fusion transcript.
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case_images: PMC11148225_01_fonc-14-1375737-g002.jpg
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case_images: The spinal biopsy results indicated the presence of immature/blast-like cells with eccentric nuclei within the spaces of the bone trabeculae ( Figure 2A ). Giemsa-stained promyelocytes displayed round nuclei and hypergranular cytoplasm ( Figure 2B ). MPO ( Figure 2C ). Multiparameter flow cytometry of BM aspirate detected 78% blasts and suggested an immunophenotype that was positive for CD13, CD33, CD117, and MPO, and negative for CD3, CD10, CD11b, CD14, CD15, CD19, CD34, CD71, CD79a, and HLA-DR, corresponding to APL features. Notably, cytogenetics G-band analysis of BM cells revealed a normal male karyotype (46, XY) ( Figure 2D ). HealthCare Biotechnology Co., Ltd.) on BM aspirate suggested the absence of PML-RARalpha dual-fusion translocation ( Figure 2E ). However, three green FISH signals suggested the presence of RARalpha translocation ( Figure 2E ). This finding was subsequently validated using the RARalpha break-apart probe detection kit (FP-043, Wuhan HealthCare Biotechnology Co., Ltd.) ( Figure 2F ). Sanger sequencing further confirmed the presence of PLZF::RARalpha exon 3-exon 2 fusion transcript ( Figure 2G ).