case_images: PMC11272519_01
case_images: Imaging and clinical course of Case 1. (A-C) Brain MRI showed no abnormal signals or atrophy in the cerebellum. (D) PET-CT showed hypermetabolic lymph nodes in the mediastinum (4R group), with the largest measuring 3.2 cm x 2.1 cm. (E) Fine-needle aspiration cytology of the mediastinal lymph node (Papanicolaou stain [x 400 magnification]) showed undifferentiated small cell carcinoma cells. (F) Timeline of the clinical course in Case 1.
case_images: fimmu-15-1431585-g001.jpg
case_images: PMC11272519_02_fimmu-15-1431585-g001.jpg
case_images: f1
case_images: Test results of serum and CSF using indirect immunofluorescence assays. (A) Negative controls without MAP1B antibodies in the serum. (B) Positive controls from a patient with classical anti-MAP1B. (C) Serum MAP1B-IgG test results (1:30) of Patient 1. (D) CSF MAP1B-IgG test results (1:30) of Patient 1. (E) Serum MAP1B-IgG test results (1:30) of Patient 2. GFP, green fluorescent protein; Neg Con, negative control; Pos Con, positive control.
case_images: fimmu-15-1431585-g002.jpg
case_images: PMC11272519_02_fimmu-15-1431585-g002.jpg
case_images: f2
case_images: The tissue-based assay was positive for serum paraneoplastic antibody, and the cell-based assay was positive for anti-PCA-2 (MAP1B) (titer 1:30,  Figures 2A, B, E ).
case_images: PMC11272519_02
case_images: Imaging and clinical course of Case 1. (A-C) Brain MRI showed no abnormal signals or atrophy in the cerebellum. (D) PET-CT showed hypermetabolic lymph nodes in the mediastinum (4R group), with the largest measuring 3.2 cm x 2.1 cm. (E) Fine-needle aspiration cytology of the mediastinal lymph node (Papanicolaou stain [x 400 magnification]) showed undifferentiated small cell carcinoma cells. (F) Timeline of the clinical course in Case 1.
case_images: fimmu-15-1431585-g001.jpg
case_images: PMC11272519_02_fimmu-15-1431585-g001.jpg
case_images: f1
case_images: Test results of serum and CSF using indirect immunofluorescence assays. (A) Negative controls without MAP1B antibodies in the serum. (B) Positive controls from a patient with classical anti-MAP1B. (C) Serum MAP1B-IgG test results (1:30) of Patient 1. (D) CSF MAP1B-IgG test results (1:30) of Patient 1. (E) Serum MAP1B-IgG test results (1:30) of Patient 2. GFP, green fluorescent protein; Neg Con, negative control; Pos Con, positive control.
case_images: fimmu-15-1431585-g002.jpg
case_images: PMC11272519_02_fimmu-15-1431585-g002.jpg
case_images: f2
case_images: The tissue-based assay was positive for serum paraneoplastic antibody, and the cell-based assay was positive for anti-PCA-2 (MAP1B) (titer 1:30,  Figures 2A, B, E ).
case_images: Imaging and clinical course of Case 2. (A-C) Brain MRI showed no abnormal signals in the bilateral temporal lobe and hippocampus. (D) PET-CT showed hypometabolism in the left parietal lobe, frontal lobe, temporal lobe, left caudate nucleus, left hippocampus, and right cerebellum. (E) Timeline of the clinical course in Case 2.
case_images: fimmu-15-1431585-g003.jpg
case_images: PMC11272519_02_fimmu-15-1431585-g003.jpg
case_images: f3
case_images: The brain MRI of the bilateral temporal lobe and hippocampus was normal ( Figures 3A-C ). To further screen for the primary cause, the patient underwent whole-body PET-CT imaging, which revealed hypometabolism in the left parietal, frontal, and temporal lobes; left caudate nucleus; left hippocampus; and right cerebellum ( Figure 3D ).