case_images: PMC11825189_01
case_images: Imaging findings before MTX withdrawal.. (A) Lateral view on X-ray at the first visit shows a reduction in the T7 vertebral body height and an increase in thoracic kyphosis (white arrow). (B) Axial view of the T7 vertebral body on CT shows osteolytic changes on the left side of the T7 vertebral body (white triangle). (C) Sagittal view on the T1-weighted MRI shows hypointense changes in the T7 vertebral body (white arrow). (D) Sagittal view on the T2-weighted MRI shows hypointense changes in the T7 vertebral body (white arrow). (E) Sagittal view of T2-weighted short-tau inversion-recovery (STIR) MRI shows hyperintense changes in the T7 vertebral body (white arrow). (F) Axial view of the T7 vertebral body on MRI shows the toxic twin-leaf sign around the posterior wall of T7 (white arrow). (G) Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) shows strong uptake in the T7 vertebral body (white arrow).. MTX, methotrexate; CT, computed tomography; MRI, magnetic resonance imaging.
case_images: cureus-0017-00000078960-i01.jpg
case_images: PMC11825189_01_cureus-0017-00000078960-i01.jpg
case_images: FIG1
case_images: An X-ray scan at the first visit showed a reduction in the T7 vertebral body height and an increase in thoracic kyphosis (Figure 1A). Computed tomography (CT) revealed osteolytic changes on the left side of the T7 vertebral body (Figure 1B). Magnetic resonance imaging (MRI) showed hypointense changes on T1- and T2-weighted images and hyperintense changes on T2 short-tau inversion recovery (STIR) images of the T7 vertebral body (Figure 1C-1E). A toxic twin-leaf sign  was found around the posterior wall of the T7 vertebra, indicating neoplastic changes, which initially led to the suspicion of a spinal tumour (Figure 1F). However, it was difficult to distinguish it from a neoplastic lesion because the patient already had a vertebral compression fracture at the T7 vertebra (Figure 1G).
case_images: Pathological findings from the needle biopsy under CT scan of the T7 vertebral body.. (A) Haematoxylin and eosin stain reveals the proliferation of medium-sized lymphoid cells infiltrating the bone marrow. (B) Lymphoid cells were positive for CD20. (C) Lymphoid cells were also positive for Ki67. (D) Lymphoid cells were negative for CD3. (E) EBER-ISH: Epstein-Barr virus was not detected by in situ hybridisation. Magnification: A, B, C, D, E x200.. EBER-ISH, Epstein-Barr virus-encoded RNA in situ hybridisation; CT, computed tomography.
case_images: cureus-0017-00000078960-i02.jpg
case_images: PMC11825189_01_cureus-0017-00000078960-i02.jpg
case_images: FIG2
case_images: Considering both the pathological findings and the MTX treatment history, the pathologist indicated the possibility of diffuse large B-cell lymphoma (DLBCL) or MTX-LPD, and no evidence of cancer metastasis was found (Figure 2).
case_images: Imaging findings after MTX withdrawal and posterior fusion of the thoracic spine.. (A) Anteroposterior (A-P) view on postoperative X-ray shows the thoracic posterior fusion with spinal instrumentation from T5 to T9. (B) Lateral view on postoperative X-ray shows the posterior fusion with spinal instrumentation from T5 to T9. (C) Sagittal view on T2-weighted MRI two weeks after MTX withdrawal shows tumour regression of the T7 vertebra (white arrow). (D) Axial view of the T7 vertebral body on MRI shows that the toxic twin-leaf sign had almost disappeared around the posterior wall of the T7 vertebra (white arrow). (E) Sagittal view on MRI (STIR) 30 months after MTX withdrawal shows that the tumoral lesion remains obliterated (white arrow). (F) Sagittal view on CT scan 30 months after MTX withdrawal shows a solid union of T7 vertebra, bridging to the caudal vertebrae (white arrow).. MTX, methotrexate; MRI, magnetic resonance imaging; CT, computed tomography.
case_images: cureus-0017-00000078960-i03.jpg
case_images: PMC11825189_01_cureus-0017-00000078960-i03.jpg
case_images: FIG3
case_images: Posterior spinal fixation for the T7 thoracic compression fracture was performed immediately after the withdrawal of MTX (Figure 3A, 3B). T7 vertebra was observed on MRI two weeks after MTX withdrawal (Figure 3C, 3D). Thirty months after MTX withdrawal, the tumour remained obliterated, and a solid union of the T7 vertebra was observed (Figure 3E, 3F).