case_images: PMC11228158_01
case_images: FDG-PET/CT images of the patient. (A) The pre-treatment scan (July 2022) revealed diffuse bone FDG uptake (SUVmax 15.6) and multiple lymph node enlargements adjacent to the right iliac vessels (yellow arrow) showing increased FDG uptake (SUVmax 13.8). (B) The scan before the 5th cycle of treatment (February 2023) revealed a significant reduction in bone FDG uptake (SUVmax 5.3) and regression of the enlarged lymph nodes (yellow arrow). (C) The scan conducted at the 14th month post-treatment initiation (November 2023) showed normal systemic bone FDG uptake and no evidence of disease. FDG, fluorine-18 fluorodeoxyglucose; PET/CT, positron emission tomography/computed tomography; SUVmax, maximum standardized uptake value.
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case_images: FDG-PET/CT revealed diffuse bone FDG uptake [maximum standardized uptake value (SUVmax) 15.6] with a pathological fracture of right femoral neck and multiple parailiac lymphadenopathies showing increased FDG uptake (SUVmax 13.8) ( Figure 1A ). Compared to the pre-treatment level, FDG-PET/CT revealed a significant reduction in bone FDG uptake and regression of the lymph nodes adjacent to the right iliac vessels, indicating a partial response ( Figure 1B ). Figures 3E-H ). Furthermore, at the 14th month, FDG-PET/CT scan showed a normal systemic bone FDG uptake and normal-sized lymph nodes adjacent to the right iliac vessel, confirming complete remission ( Figure 1C ).
case_images: Curves of key laboratory tests. (A) Hemoglobin level (orange) and platelet count (blue). Arrows indicate the timing of antitumor treatment. (B) Serum levels of neuron-specific enolase (orange), cytokeratin 19 fragment (gray), and lactate dehydrogenase (blue). HB, hemoglobin; PLT, platelet; NSE, neuron-specific enolase; Cyfra21-1, cytokeratin 19 fragment; LDH, lactate dehydrogenase.
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case_images: Blood tests revealed a hemoglobin level of 71 g/L, a platelet count of 54*10^9/L, and a white blood cell count of 8.62*10^9/L ( Figure 2A ). Serum levels of cytokeratin 19 fragment (71.50 ng/ml) and neuron-specific enolase (139.00 ng/ml) were elevated, while the levels of other tumor markers were within the normal range ( Figure 2B ). Particularly noteworthy was the serum lactate dehydrogenase level, which was elevated to 3000 U/L ( Figure 2B ). However, a repeat blood test revealed contraindications for chemotherapy, with a hemoglobin level of 70 g/L and a platelet count of 38*10^9/L ( Figure 2A ). Over the next two months after starting treatment, the patient experienced recurrent episodes of declining hemoglobin and platelet count, with the hemoglobin dropping to a minimum of 44 g/L and the platelet count reaching a minimum of 46*10^9/L ( Figure 2A ). Fortunately, the patient experienced substantial pain relief, and tumor markers decreased significantly from pre-treatment levels (cytokeratin 19 fragment and neuron-specific enolase levels dropped to 24.90 ng/ml and 23.20 ng/ml, respectively) ( Figure 2B ). After cycle 2, the patient's platelet count and hemoglobin level gradually recovered after a transient decline ( Figure 2A ). Serum lactate dehydrogenase level also decreased significantly to 878 U/L ( Figure 2B ).
case_images: Hematoxylin-eosin (H&E) staining and immunohistochemical evaluation of the bone marrow aspiration and biopsy. (A) H&E staining of the pre-treatment bone marrow smear. (B) H&E staining of the pre-treatment bone marrow biopsy. (C, D) Immunohistochemical evaluation of P40 and PD-L1 for the pre-treatment bone marrow biopsy. (E, F) H&E staining of the bone marrow smear and biopsy obtained at the 12th month post-treatment. (G, H) H&E staining of the bone marrow smear and biopsy obtained at the 14th month post-treatment.
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case_images: The bone marrow smear revealed infiltration of malignant tumor cells ( Figure 3A ). The bone marrow tissue biopsy confirmed metastasis of undifferentiated carcinoma with elevated PD-L1 expression (combined positive score 80) ( Figures 3B-D ). Figures 3E-H ). Furthermore, at the 14th month, FDG-PET/CT scan showed a normal systemic bone FDG uptake and normal-sized lymph nodes adjacent to the right iliac vessel, confirming complete remission ( Figure 1C ).