case_images: PMC11288880_01
case_images: Skin lesion on the chest (A,E), back (B,F), abdomen (C,G), and right inner thigh (D,H) of the patient before and after treatment (Day 9).
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case_images: On admission, physical examination showed extensive skin lesions on his chest, back, abdomen, and right inner thigh (Figure 1) and enlarged lymph nodes in the neck, axilla, and groin. After 9 days of treatment, the skin lesions gradually reduced in size and disappeared markedly (Figure 1).
case_images: BPDCN cells in bone marrow smear before (A,B) and after (C,D) treatment using Wright's staining. The quantity of BPDCN cells significantly decreased in bone marrow smear after treatment.
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case_images: Many BPDCN cells were detected in the peripheral blood smear (60%), bone marrow aspirate smear (73.5%) (Figure 2). Importantly, BPDCN cells significantly decreased (4.5% in the bone marrow and 2% in the peripheral blood) after the first course of both drugs administration (Figure 2), indicating that the elderly patient presented with CR in the bone marrow.
case_images: Immunophenotypes of malignant cells in lymph nodes (A-H) and skin tissue (I-L) using immunohistochemistry (IHC). The tumor cells proliferated actively. CD7, CD43, CD56, CD123, and Ki-67 were positively expressed in BPDCN cells, and CD3, CD20, CD34, MPO, Lysozyme, and PAX-5 were negatively expressed in BPDCN cells.
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case_images: Meanwhile, BPDCN cells were also distributed in cervical lymph nodes, and skin dermis tissue (Figure 3).
case_images: FCM results showed a lot of BPDCN cells in bone marrow. BPDCN cells were positive for CD4, CD56, CD123, TCL1, and CD303. BPDCN cells significantly decreased in bone marrow after treatment (from 54.61 to 7.19%).
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case_images: Immunophenotyping using flow cytometry (FCM) further showed a large number of BPDCN cells (54.61%), expressed positively for CD4, CD56, CD123, TCL1, and CD303, in the bone marrow (Figure 4; Table 1).
case_images: PET/CT scan showed multiple enlarged lymph nodes and splenomegaly. (A) showed enlarged lymph nodes above and below the diaphragm; (B) showed enlarged lymph nodes in cervical part (orange arrows) and abdominal part (yellow arrows), and splenomegaly (blue arrows).
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case_images: Positron emission tomography/computed tomography (PET/CT) further demonstrated that there were multiple lymph node enlargements above and below the diaphragm, and splenomegaly (Figure 5).
case_images: Schedules of treatment strategy and efficacy evaluation. (A) To avoid tumor lysis syndrome, initial dose of venetoclax was 100 mg/day oral, and the dose was increased to 200 mg/day for 27 consecutive days. Azacitidine was given with the dose of 100 mg/day for 7 consecutive days. One cycle was 4 weeks (28 days). (B) Efficacy evaluation for blood cell count was performed every 2 days during the combination therapy period.
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case_images: Once confirmed, this patient began treatment with the oral BCL2 inhibitor venetoclax (100 mg on the first day and 200 mg for 27 consecutive days) and subcutaneously administered azacitidine (100 mg once daily for 7 consecutive days) (Figure 6A). Meanwhile, the hemoglobin and platelet counts improved significantly (Figure 6B).