case_images: PMC10917982_01
case_images: The patient's hematologic findings. (A) WBC count before starting, during, and after stopping Osimertinib, (B) ANC before starting, during, and after stopping Osimertinib, (C) Hb level before starting, during, and after stopping Osimertinib, and (D) Platelet counts before starting, during and after stopping Osimertinib. AA, aplastic anemia; ANC, absolute neutrophil count; Hb, hemoglobin; Plt, platelets; WBC, white blood cell.
case_images: fonc-14-1275275-g001.jpg
case_images: PMC10917982_01_fonc-14-1275275-g001.jpg
case_images: f1
case_images: Treatment with subcutaneous filgrastim 300 mcg for three days improved neutropenia to the normal level with ANC of 2.3 x103/uL ( Figure 1B ). Before initiating Osimertinib, the patient's blood tests were within normal range ( Figure 1 ). However, one week after starting Osimertinib, mild pancytopenia was observed, with a decrease in WBC to 3.3 x103/uL, ANC to 1.8 x103/uL, Hb to 11.5 gm/dL and PLTs to 140 x103/uL ( Figure 1 ). Hb of 9.3 gm/dL and PLTs of 24 x103/uL ( Figure 1 ). However, the levels remained below the normal range.
case_images: The patient's bone marrow biopsy findings. (A) Bone marrow trephine biopsy (low power) is markedly hypocellular with <5% cellularity showing marked depression of the trilineage hematopoiesis [Hematoxylin and eosin, H&E, staining x4]. (B) Bone marrow trephine biopsy (high power) showing fatty replaced intertrabecular spaces with few nucleated cells and almost absent megakaryocytes [H&E staining x20].
case_images: fonc-14-1275275-g002.jpg
case_images: PMC10917982_01_fonc-14-1275275-g002.jpg
case_images: f2
case_images: No abnormal infiltrates, lymphoid aggregate, or granuloma was identified ( Figure 2 ).